Date: Tue, 21 Sep 1999 15:20:25 -0700 The early 93's came with 1.3 bar caps. Then Mazda had a
recall on the cooling system because it was suspected of
leaking coolant and starting engine bay fires. The recall had
some cooling system components replaced to withstand more
heat, plus the pressure cap was changed to a 0.9 bar cap.
I have also seen FDs with 1.1 bar caps, so don't know when
these where used - maybe between the original 1.3 and the
0.9 recall caps.
Anyway, I believe that 1.3 bar is too much pressure for the FDs
cooling system, and if anyone is using one, they should replace
it. It may also mean that the cooling system recall has not been
done on the car yet. If you suspect the recall has not been done,
call Mazda Customer Service at 1-800-222-5500 and give them the
VIN of the car. They can tell you if and when the recall(s) where
done.
The only draw back of the lower pressure cap is that if you run the
car hard, it may want to boil over. You should use at least 40 %
ethylene glycol (antifreeze) with distilled water and a bottle of
Redline water-wetter to ensure good cooling system performance.
If your antifreeze ratio is too low, you are also decreasing the boiling
temperature of the coolant, but getting slightly better heat transfer to
the coolant.
_________________
Date: Thu, 20 Nov 1997 01:24:40 -0800 (PST) Public service announcment
If you happen to be running a radiator pressure cap that says .9 on it,
you will want to upgrade it to one that says 1.1 (this is bar BTW, and is
equiv to 13psi cap, and 16psi cap)
I have seen quite a few .9 caps, and only a couple 1.1, and am not sure
when Mazda switched.. (coolant recall?)
_______________
Date: Thu, 20 Nov 1997 07:51:00 -0600 The caps were changed from 1.1 to .9 when Mazda did the coolant recall.
This is also the reason people started hearing percolating noises in their
cooling systems after turning off the engines. The lower pressure allows
the coolant to boil at a lower temperature, and the turbo area is very
hot. I never had this percolator sound until after the coolant recall.
Date: Fri, 30 Apr 1999 07:30:08 PDT I would agree with Kyle on going with the stock t-stat next
time around. According to Peter, for optimal performance the ECU
wants to see a water temp reading of no less than 180. Below
that point, the computer is still is warm up/protective mode.
Solenoids, secondary butterflies and injectors all work as if
the car was still cold. This is especially a problem on the
highway since temps will drop below the 180 mark and get pretty
close to 170. The difference in the minimum running temperature
on the highway at around 70 mph is only about 10 degrees, and
as it turns out, that's 10 degrees too cold.
_______________
Date: Fri, 26 Mar 1999 11:31:12 -0500 Since the AST issue has surfaced again, I am re-posting an AST article I
wrote last year. I have had no problems with about 4 track events so far.
The air-separation tank is in parallel with the radiator. Once the thermostat
opens, the hot coolant bypasses the radiator to pass through the tank, and is
returned, hot, to the waterpump inlet to re-enter the engine housing ports.
Its purpose is first to collect air/vapor in an upper, stagnant chamber.
Then by thermal expansion of the fluid and gas, it purges the collected air
into the vented overflow bottle by way of a 3rd hose that ends in the bottle
below the coolant level. Air bubbles rise to the top and vent to the
atmosphere. Upon cooling-contraction, coolant from the bottle is pulled back
into the system. A probable source of the air is a little leakage, from the
combustion chambers, by the o-rings.... mabe at cold start.
The coolant that flows to the separation tank comes from the top of the
thermostat housing, where a mini chamber is cast into the housing. The entry
into this chamber can be seen after removing the fill cap as a 10mm hole. The
only chamber exit is the hose to the separation tank. The purpose of the
mini-chamber is to encourage any air that is passing below, from the open
thermostat to the radiator, to rise up and be sent ( with coolant ) through
the small bypass line to the separation tank.
Problems With Tank Removal/Bypass line:
IMO, simple removal of the tank and splicing the lines is not recomended for
two reasons: First, it provides a bypass to the radiator that is not cooled.
But more importantly, it encourages any air that may collect at the top of the
housing to be pushed through the engine passages when the thermostat is open.
Remember that air movement to the separation tank was the primary function of
the mini-chamber at the top of the thermostat housing.
A Simple Fix:
I removed the tank and installed the new cap assembly at the thermostat
housing as others have done. But I also plugged the old connections (2) at the
nipples and removed the hoses. This eliminated the bypass, and created a modest
stagnant chamber at the top of the thermostat housing to purge out air as
before with the tank. It appears to work fine, perhaps this will satisfy both
pro-tank and anti-tank groups. As a final touch, I may insert an aluminum
baffle to help minimize turbulance in the 'new' chamber. With this mod, the
original cast mini-chamber traps coolant, so make sure it has some antifreeze
for winter climates. Ideally, a small hole in the bottom of the mini-chamber
would solve this little problem and add to the effective mini-AST volume.
____________________
From: Jose L. Corraliza [mailto:jcorraliza@snip.net] According to Dave (at KD Rotary), the stock AST has different chambers
and baffles which serve to separate the air from the coolant.
The aluminum ASTs are, in essence, a tin can with 3 nipples
welded on to it. Sure they don't split, but they don't remove
the air from the system as well as the stock tanks.
____________________
Date: Sat, 22 May 1999 00:33:54 -0500 > The cap on the filler neck should not be a pressure cap. The overflow Let me set the record straight here. Cooling systems are a specialty area
of mine, and I am quite positive that the following is correct:
In the strictest sense, both caps are "pressure caps" in that they hold
pressure in the system once it warms up. However, only the cap on the AST
is a pressure relief cap - the traditional type of radiator cap. You'll
notice the large spring that relives pressure, and the small disk in the
center that opens under vacuum to return coolant. The cap on the filler
neck part of the water pump/thermostat housing only acts to seal that
opening of the cooling system.
When ever your engine is running and the thermostat is open, there is
coolant moving through the AST. A small volume of coolant is tapped off
just past the thermostat and goes to the AST. Here it becomes nearly
stagnant, and any entrained air AND vapor bubbles rise up to the surface.
Coolant is then returned to the radiator, right next to the lower radiator
hose outlet (leading to the water pump inlet). Coolant that flows through
the AST bypasses the radiator, but that is the only way to get coolant into
the AST in the first place(there is the same large pressure drop across the
AST as the radiator).
The AST also acts a bit as a surge tank for the cooling system. When the
water pump accelerates (with the engine), there is a certain amount of lag
in getting the water flowing, due to its mass (needs to increase momentum).
This can cause the water pump to cavitate because it is trying to suck water
from a restrictive source - the radiator. Instead, it is able to draw down
coolant from the AST, which in turn can draw in from the atmosphere (through
the weakly sprung vacuum relief disk on the pressure cap). Actually, the
AST draws from the overflow tank, but in this transient surge role, it
really doesn't care, it just wants an easy path to get any fluid at
atmospheric pressure.
There is no need to replace the cap that goes on the water pump unless the
cap's rubber gasket goes bad. Also, most decent garages can test pressure
caps with a special pressure cap pump, but replacing an old one is not a bad
idea either.
Chris Hoke: sounds like your dealer put the caps on in the wrong spots. The
cap with the pressure number and spring loaded plunger should be on the AST
(the black tank by the intercooler - just to make sure there's no confusion
in what the AST is). The cap with only a rubber gasket on the back side
goes on the engine.
yes I am sure. I read the detail on the caps, plus just ordered
replacement caps for both from Mazda Comp. Of course both
need to be pressure caps, when block pressure get to point X it
overflows coolant to the swirl tank (round cap with black top).
this is the presurized overflow. this cap is normally higher
pressure than the filler neck cap to allow water with air bubble
to overflow to the swirl tank where the air separates from the
coolant. A line at the bottom of this tank goes to the radiator
to return coolant to the eng/rad when pressure drops a little.
If the swirl tank is full and pressure exceeds it cap rating, the
cap allow overflow to the NON pressurized overflow tank (a 3 part
system. Cooling in the block causing suction is supposed to
draw coolant back from the overflow tank to swirl tank to block
when operating properly.
____________________
From: les (lesd@earthlink.net)
While the elimination of the AST will simplify the under hood
plumbing, I think you still need to worry about how the system
will get rid of gasses in the system.
Notice I said gasses, not air.
It is my impression that the reason Mazda went to the effort of
making a fancy separation tank is because there is a chance
that even 'good' engines can leak tiny amounts of exhaust into
the coolant. Especially as the engine ages, and as the engine
components expand and contract at different rates because of
the different metals ( AL and iron ).
When you have pockets of gas in the coolant, there can be hot
spots that don't get the best cooling, and that can exasperate
the situation.
____________________
From: Shane Baker (sbaker@null.net)
The gasses are formed as a result of localized boiling, especially
around the spark plugs. At least, this is what the guy who used to be on
this list (and maybe still is) that designs engine cooling systems for a
living told me.
The other thing that the AST does that I never hear mentioned (I wish I
could remember where I read this) is act as a resevoir for the water pump
to draw from to avoid cavitation since the radiator offers enough
restriction to essentially starve the water pump in some conditions. I
read it fairly recently, so I should be able to it.
____________________
From: Steve Cirian
Dom wrote:
The failure of the aftermarket ones is worrisome, but I think we can ignore the
incorrectly fabbed ones (provided a person didn't get one of these...) in determining
if an AST should be used. And I think we can ignore the OEM failures, since my personal
debate was elimination vs an aftermarket one (see previous comment on worries about
aftermarket ones) .
I have gotten a couple of responses that say that one issue is that they need to burp
it regularly, especially at track events. This is not a complication in the sense of a
failure, but is still not a "perfect" solution. Plus if there are gas bubbles in the
coolant, you could get cavitation in the water pump. (that point assumes that the ASTs
really do eliminate all the gasses.)
____________________
From: Dave McAnaney (mcananey@yahoo.com)
I was running my car for years with the original
TriPoint AST with no problems. Being an engineer, I
felt that the RX-7 designers put the AST there for a
reason, so I did not eliminte it.
When I upgraded my intake and intercooler to the M2
large about a year ago, I lost the mounting point for
the AST and relocated it next to the intake. Bad move
- the new location was lower than the original
mounting location and air pooled in the filler neck
instead of the AST, causing the low coolant buzzer to
go off numerous times at the track. I was constantly
"burping" the system to no avail and noticing the
'sloshing water' sound in the heater core at startup.
So, I followed the majority and elminated the AST.
This worked fine on the street, but once I ran on the
track again I got the low coolant buzzer and 'puking
coolant' out the overflow. Again, I burped the system
numerous times but could not get the air out of the
system. I started thinking that I may have the
dreaded failing o-rings, but I did not have the other
symptoms (white smoke on startup, rough idle, oil in
the coolant, etc.).
I decided to un-eliminate the AST and mount it in
front of the water pump at the same height as the
filler cap. So far, so good. Although I have not
driven the car on the track since reinstalling the
AST, I have not noticed any sloshing water sounds at
startup and the coolant level seems to be
leveling-off. We'll see in a couple weeks at the heat
of Thunderhill.
[opinion] ____________________
From: Eull, Timothy R. (timothy.eull@honeywell.com)
It's interesting that you should post your question at this time. I live
here in Phoenix AZ and recently attended Sevenstock in Irvine CA. Prior to
my departure, I installed aftermarket water and oil temp gauges (water temp
plumbed on the "flat" area of the filler neck, and oil plumbed via a
threaded banjo bolt just under my filter).
Anyway, on the way to the event I saw operating temps (freeway cruising at
80 mph) in the 210 to 220 range and a spike near 240F going up a hill into
Palm Springs (ambient ~105F). Anyway, the entire time my stock gauge did
not budge from the "middle" reading.
Once I arrived at Sevenstock several people saw that I had installed the M2
AST removal kit and expressed concern that my system might have air bubbles.
Indeed it did. Unfortunately when it came to proper burping and filling of
the system (including removal of the manifold hose and topping that off as
well) I was totally in the dark. Also, the folks from Pettit strongly
discouraged use of the elimination kit for the very reason you suggested
(eliminating the system's ability to bleed air from the system).
Anyway, after winning a TriPoint AST at the event, I installed it that night
in the parking garage of my hotel with the few crude tools I had brought
with me, properly filled and burped the system, and headed for home the
following day. On average the gauge readings I observed were 10 degrees
cooler, given similar conditions, than the trip out.
Does this mean that the car will run cooler on average with the AST versus
without? I'm not sure. The AST definitely gives you additional coolant
capacity, but I've got to believe that a properly filled and bled system
that eliminates as much air as possible will probably work just as well. My
operating environment is one of the most extreme in the U.S.! For now,
I'll stick with the aftermarket AST.
____________________
Date: Fri, 20 Jul 2001 07:57:46 -0600 I have a Tri-point AST. It was mounted on the bracket on the PFS
intercooler (which certainly looked like it blocked a lot of the air
flow through that). It also had to have very long lines going to and
from it.
Last month I installed the efini "Y" pipe, and removed the air pump
(as I have no catalytic converters). I used the Greedy pulley kit to
get the belt length issue resolved. I moved the AST to where the air
pump was, and fabricated an aluminum bracket (off the air pump
mounting holes). I put a hole every 1/4" or so up the bracket so I
could mount it as high as possible. The lines to/from the AST are now
very short. The PFS intercooler now has a clear cavity behind it
(room for fans/a fan). The AST works very well in this position (the
filler neck on the engine is now always almost completely full of
coolant).
I think this is the best/most effective mod. (or series of mods.) I've
ever done to the car. I also fab'd an aluminum bracket to support the
plastic air tank on top of the engine (mostly for looks - it was
supported by the "Y" pipe output plastic pipe support - I removed that
ugly heavy part).
____________________
Date: Fri, 20 Jul 2001 10:42:43 -0700 Yeiks! The AST vs. non-AST debate is beginning to look like the venerable synthetic
vs. nonsynthetic oil debate. No real hard data and no likelihood of ever getting any.
Just lots of anecdotal evidedence and opinions. So, here is my opinion with absolutely
nothing to back it up. 8-)
First, water (or coolant in this case but lets stick with water) has air dissolved in
it. You can't see it, but its there. For example a glass of water sitting on your kitchen
counter contains approximately 2% air by volume. If you heat up this glass of water to
lets say just below boiling about half of that air comes out of solution in the form of
tiny bubbles. Pressure changes act in a similar, but opposite way - higher pressure more
dissolved air, lower pressure less dissolved air. But, since on the third gen there is
only a 13psi difference between a pressurized coolant system and an unpressurized system
this effect is small compared to the large temperature differences experienced by the
cooling system.
Well, lets get to the meat of this editorial, my guess is that the AST was not put
there to remove pockets of air that remain in the system after filling it (which, in my
experience, it doesn't do), but it was put there to reduce the concentration of dissolved
air in the coolant. How does it do this? Remember, in the previous paragraph when water
is heated (for example, as it passes through the engine) dissolve air comes out of
solution as tiny air bubbles which are so small they are swept along with the flow. With
an AST, these tiny air bubbles are removed before the coolant goes to the radiator.
Without the AST the coolant and air bubbles go into the radiator, the fluid is cooled,
and some of the tiny bubbles are reabsorbed into solution before going back into the
engine, starting the process all over again. In any case, without the AST after shutdown
when the engine cools all the tiny bubbles go back into solution.
So, as I see it there may be two concenquences with removing the AST and having a high
level of dissolved air in your cooling system. The first one is corrosion. Air has oxygen
in it, dissolved oxygen, especially at elevated temperatures, is very corrosive. Sure,
your antifreeze keeps this in check for the most part, but only if you religiously change
it once a year. Lowering the level of dissolved oxygen certainly could help reduce the
amount of corrosion in the cooling system over the life of the engine. The second problem
with air dissolved in the coolant is efficiency. Remember, as the coolant is heated by the
engine the dissolved air comes out of solution in the form of tiny air bubbles. This air
bubble/coolant mixture is not as efficient at removing heat as a purely liquid coolant
mixture.
In conclusion, IMHO, eliminating the AST may result in a slightly increased rate of
corrosion in the cooling system and a slight decrease in cooling efficiency. Since, most
people will not keep their cars long enough to notice the former and a cooling system in
good shape has enough excess cooling capacity to negate the latter, eliminating the AST
will not have any immediate adverse effects on a well maintained cooling system. But, if
you don't religiously maintain your cooling system, need every last percentage of cooling
capacity you can get, or intend on keeping your car forever, it may be a good idea to keep
the AST (but, certainly not the stock AST).
____________________
from les (lesd@earthlink.net) Stock OEM Ast's have no baffles either.
I've sawed one apart before.
from les (lesd@earthlink.net)
I don't think localized boiling would be it.
Boiling water makes water vapor(steam), not air.
High school physics.
As soon as the water vapor (steam) cools, it collapses
right back to liquid again, leaving no bubbles.
When the engine cools, there would be no bubbles because
of any kind of boiling.
I agree with another poster, there is trace combustion gas
leakage past the O rings. The AST is designed to purge
that ongoing process.
____________________
From: tworx7s (tworx7s@zbzoom.net)
Simply put one of those vent-lever caps on the remaining filler neck,
instead of the generic non-thermo cap, which is basically just a lid. You
can then use the vent lever to "burp" the system, but if you follow the
proper procedure for filling the cooling system in the first place, you
shouldn't get enough air in the system to cause potential danger. It would
essentially become like any other system. HOWEVER, if you race your car and
it repeatedly heeats up and cools down, you will find you'll need to burp it
more often... there, there now, that's a GOOD baby :-)
____________________
from Max Cooper (max@maxcooper.com)
The plugs you use to eliminate the AST are points of failure themselves. I
popped two of those HELP! brand rubber caps before I switched to short
sections of hose with bolts clamped in the ends. They are ugly, but they
work. I am looking at some caps from McMaster-Carr or perhaps installing a
hose from nipple to nipple with a flow restrictor in the middle.
I agree that the simplification is nice.
I lost a motor last year, but I do not think it was related to the AST
elimination in any way. The new motor has been fine for >10,000 miles with
no AST.
I do wonder sometimes why the car had one in stock form. Mazda did a lot of
work to eliminate weight and unnecessary parts. They even moved the coils so
the spark plug wires could be short and thus light. If the AST wasn't good
for something, it would not have been there. My car seems to be fine without
it, but these thoughts do nag me sometimes.
The car should be able to expell excess gas through the overflow tank. I do
not ever have to burp the coolant. It has been more than 8,000 miles since I
opened the filler cap.
____________________
from dbeale (dbeale@harddata.com)
Those who have removed it, do still have one, sort of. The space on
the engine filler neck becomes the AST. Rather small, but perhaps ok.
____________________
From: Shane Baker (sbaker@null.net)
You may agree with that person if you like, I'm going to stick with the
person who designs cooling systems for a living :) I'm sure many of you
know whom I am talking about, I just don't like to bring innocent
bystanders into a thread that they didn't ask to be in.
Not another 'high school physics' debate... please... I give up
:). (Sorry, just kidding, really... it just seems that somehow it is
always me who is on the receiving end, whether it be someone trying to
convince me that tire traction has nothing to do with contact patch size
or whatever... it's kind of funny that it always happens to me).
Anyway, what you said about the steam makes sense, however, the cooling
system is not filled with pure water. The chemical interactions that
might take place at high temperatures with ethylene glycol and water and
the various metals and whatever else might be in there are not necessarily
going to revert at cooler temperatures. I'm not saying that I know what
these interactions are or that they even happen, just that it's easy to
suppose that they might. If nothing else, I can say that water is self
ionizing and produces hydrogen ions (and hydroxide), some of which would
have to produce a hydrogen gas. I am willing to go out on a limb and
say, with absolution, that this is not the gas that we are trying to
eliminate (I'm not a chemist, but I recall that this is not a 'popular'
reaction... good thing or we'd be in trouble) and I'm only mentioning
because it suggests that, while high school physics provide a valuable
foundation, they are pretty much never adequate for completely explaining
the real world... and it's pretty much the only thing that I know on
the subject to make that point :). Like you said, we're concerned about
'gases', not 'air'. The question is, what does a boiling ethylene
glycol/water/whatever solution produce? I'm not trying to condescend or
anything, just further the discussion.
The exhaust gas theory is interesting, and there may be some merrit to it,
I don't know.
According to 'cooling system guy', the orifice sizing of the AST is as
important if not more important (I'm recalling from memory, don't blame
him if I screw it up :) than the AST tank size. The orifice sizing will
control the flow through the AST to both keep the fluid relatively
stagnant in the tank but also (probably more importantly) to keep too much
fluid from going through it because it is basically a route for coolant to
travel that bypasses the radiator.
I tried to find that text that I read suggesting that the AST actually
helps stop cavitation under some circumstances, but I didn't. I'll keep
looking though.
____________________
Date: Wed, 28 Jan 98 19:21:00 -0500 >As I recall some of you have put Pettit Racing aluminum coolant air I have the pettit coolant tank.....hasn't leaked yet! and I can't see it
exploding since its aluminum and not plastic with a seam like the
stocker...
________________
Date: Wed, 24 Mar 1999 09:11:07 -0500 I purchased the Pettit AST and it came with new clamps, a new
cap, and the tank.
I then needed additional hardware, (1-10mm bolt & 2-10mm nuts) and a
mounting bracket.
The welds on the tank looked OK, definitely hand welded.
The finish was very nice.
When I dropped it in, the mounting tab that was welded to the tank was
1" too low and about 1/2" off toward the firewall.
Since it was 8:30 on a Wednesday night I ran up to get the hardware,
hacksawed, drilled, and bench ground a 1/8" thick aluminum piece that I
found in the garage.
Fortunately I anticipated such an event, so I was up to the fabrication
work and the holes & slot lined up the first time.
This really was not a big deal but ANY other after market whatever that
I have installed has ALWAYS had an installation sheet to warn of these
things.
I understand that Pettit possibly switched vendors, or the FAB house
accidentally grabbed the wrong revision drawing, but that doesn't help
someone who is hacksawing a chunk of aluminum in their garage at 9:00 on
a Wednesday!
________________
Other people said as well that Pettit has fixed some of the mounting
issues as well as the requirements for "extra" parts or fabbing your own
bracket. I would call them and ask for clarification on it. --Steve
________________
Date: Tue, 03 Aug 1999 19:41:44 -0400 I and many others have used the Pettit AST tank for years without
problems. Std radiator cap works with it or you can use the
fancy vented/locking cap it comes with.
The only negative is the bitching about its cost - as is clear
from the recent posts nothing is really as simple as it seems and
if your cooling system screws up it costs you the engine.
My opinion, the AST performs an important function on the FD and
should not be eliminated. Others with equiv. experience to me
have have eliminated it and have a different opinion. Take your
choice.
_________________
Date: Mon, 22 Mar 1999 11:30:39 -0800 Replacing the stock AST is a wise move. I was always planning on doing
so but never got around to it until it was too late.
One morning I startup my 7 only to hear the coolant buzzer go off.
Popped open the hood and saw coolant all over the AST. I ended up
replacing my stock tank with Tri-points aluminum tank. I found
Tri-points to look better than Pettits. Tri-points also uses the stock
(they include a new one) AST cap instead of that standard radiator type
cap. No bracket needs to be fabricated as with Pettit's. Tri-points
bolts right up at the same stock location. The only thing you will need
that was not included (at least with mine) is a small nut to put on the
existing bolt.
One thing that was fixed by changing the leaky AST to Tri-points is the
"water rushing" noise that I used to hear under the passenger side dash
whenever I started up my 7 or sometime during idle was gone.
________________
Date: Fri, 26 Mar 1999 08:05:10 -0700 I just got my aluminum AST from Tripoint. It comes with the Mazda
pressure release (with the spring - .9 bar) cap. Wish I knew that,
could have saved the $28 Can. for the new cap I just bought. The tank
is black anodized, and looks very similar to the Pettit unit in shape
and size. Very well made, nice heavy mounting tab, comes with 3 ss
hose clamps. Don't plan soon on building these yourself. The cap
flange is intricately machined, and is actually better made than the
original Mazda one. The welds on the three spigots are first rate.
I've never seen the stock components under my hood (PFS intercooler
and cold air intake were on the car when I got it), but the tank has a
1/8" rod sticking out the bottom. I presume this is inserted into a
grommet or something on the stock intercooler parts? My only concern
is the nylon fitting on the overflow spigot. The hole in it is only
about 1/8". If I ever boil the coolant that sucker is going to be
"tested".
________________
Date: Wed, 7 Apr 1999 16:53:40 -0700 I talked to Mark at TriPoint Engineering about the caps
that come on their AST. The stock 3rd gen pressure
cap (Mazda P/N: N3A1-15-205A) without "ears" will
work, as well as an older style cap (Mazda P/N:
D316-15-205) with "ears". Both are 0.9 Kg/cm (12.8 psi),
stock rated caps (do NOT put a higher pressure cap than
that on).
TriPoint usually sends their AST with the "eared" cap
because its a little easier to take on and off, but
apparently you can have them put either on it for you.
Also, when you go to replace it (in about 1 yr), you
now have two factory caps to choose from, from your
"friendly" Mazduh dealer.
________________
Date: Thu, 8 Apr 1999 08:13:02 -0600 My Tripoint AST came with the "uneared" cap (must have met up with
Mike Tyson).
A word of warning for those with the PFS intercooler, who have ordered
the Tripoint AST. It doesn't quite fit properly. If you still want
to install it, you have two choices:
1.Drill a new hole in the PFS intercooler AST mounting tab (you have to
move the hole closer to the tube the tab is welded to).
2.Raise the AST so its tab rests above the PFS tab. Then make
a U shaped piece to join the two (it sits over the two tabs, and when
you drill holes in the right places in it you can bolt the two tabs
together using the U shaped piece).
I'm using the second method, as I believe having the tank higher is a
GOOD THING. This will force the "bubble" of air in the system to
migrate to the AST, where it will always be forced into the overflow
tank. BTW, I did check to see if the hood will clear it - it will.
_________________
Date: Thu, 8 Apr 1999 11:29:52 EDT I also had some fit difficulties w/ the PFS IC, but by slotting the hole (in
the AST, not the IC) about 3/16" in towards the body of the AST, it fit like
a charm. The AST wedges tightly against the IC discharge pipe.
_________________
Ken posts regarding problems some of the older Tri-Point ASTs. Anything
you buy now should have these issues fixed. Scott (Robert S. Ulen) posts
further down on measurements he made on his AST. --Steve
Date: Tue, 3 Aug 1999 22:45:21 EDT A growing body of evidence points to problems with some but not all Tri-Point
Air Separator Tanks (AST's). Specifically, the dimensions of the cap
housing on some Tri-Point's AST's do not meet SAE standards. This can result
in the AST's cap not relieving the cooling system's pressure at the cap
rating. (In my case, the pressure was not relieved by a 13-lb cap until
20-22 PSI was reached.)
One way to determine if your Tri-Point AST meets the SAE standard is to
measure the distance from the top lip of the cap housing to the top of the
inner hole. The SAE standard for this distance is a range of 15.53 to 16.03
mm. (My Tri-Point AST measured 14 mm). To make the measurement, put a
straightedge across the top of the cap housing and drop a piece of paper down
until it reaches the top of the lower hole. Then mark the paper, remove it
from the cap housing and measure the distance. It will take just a few
minutes to do this. For a reference point, this distance in the OEM AST
measures 16 mm.
The second way to evaluate your Tri-Point AST is to conduct an actual
pressure test on your cooling system. The pressure tester would be mounted
on the Filler Cap housing to determine the pressure at which the AST cap
activates. This, however, is not the best of tests because some caps have
been shown to provide relief at the rated pressure even with a non-SAE
compliant AST. Call these the "forgiving" caps. Therefore, this pressure
test would only show that the AST only functions with the cap presently in
use. Replacing the cap could result in the purchase of an unforgiving cap
and over-pressurization of your cooling system.
_________________
Date: Tue, 3 Aug 1999 10:37:24 -0700 I wanted to email you guys, and let you know what I have found so far about my
TriPoint AST. It seems like the 3 of us are the most involved with this possible
overpressure issue. This really concerned me, so I jumped right in to find out
what is happening with my car's cooling system. The last thing I need is a failed
O-ring, or some serious problem associated with coolant overpressure.
Last night, I did very careful and many measurements (for technique and repeatability)
of my stock AST and the TriPoint AST. This is what I found:
Stock AST
- ----------------
TriPoint AST (mine)
- ----------------------------
Measurements of Stock 0.9 Mazda Pressure Cap (no ears, no markings, almost new)
- ---------------------------------------------------------------------------------------------------------------------------
Conclusions
- ------------------
This analysis says that the stock cap and the TriPoint AST should work fine together. The
"pre-load" of the spring plunger is the same, which means it should relieve at its rated
pressure (13 psi). The "pre-load" is a very important aspect of the integrated design. If the
pre-load is more, then the required pressure to move the plunger off the seat would be higher
because of more force required to move the spring.
Ken, BTW in one of your posts, you mentioned something about a "thermally activated spring". Actually, the spring is just a spring, and it is not thermally controlled like a thermostat.
The plunger only moves due to pressure, and is solely dependent on the pre-load of the
plunger spring, and the spring constant (which in linear in this case).
Dave, in your post to me, you said your original pressure cap had the black sticker, and had
"1.3" printed on the top. Wow - that is a 18.5 psi cap. It sounds like you car has not had
the coolant safety recall. If the top fitting on your filler neck is black nylon material, and not
aluminum it definitely has not been done. Call Mazda Customer Service (1-800-222-5500),
and give them your VIN off your car. They can tell you if their records show the recall or not.
Anyway, tonight I am borrowing a coolant system pressure tester. My plan is to install the
tester/gauge on the filler neck, then start the car and record system pressure vs. coolant
temperature. After the engine is totally hot, I plan on monitoring the pressure while the
coolant goes through its fluctuations (195 to 230 deg F) during various fan running scenarios.
Then, after I shut down the engine, I will monitor coolant temp (hot soak to approx. 245) and
pressure during cooldown.
Ken, if you actually measured 14.0 mm as the neck depth on your TriPoint AST, then I would
say you got a bad one. I talked to Guy at TriPoint yesterday, and asked him what the design
dimension for the neck depth was. He said that the neck part of their AST is designed and
manufactured by a reputable radiator manufacture. If this is the case, then I would assume
that some knowledgeable engineering was put into the neck design. Based on the measurements
I did on my TriPoint AST, it looks like the dimensions are very close to the SAE specs that
Ken gave in one of his posts. Anyway, TriPoint seems to be looking into this issue, and it
maybe entirely possible that they got a bad batch of neck made by their supplier.
I will try to pass on the pressure vs temp measurement I plan on doing tonight. That will be
the true test on the function of my AST. Hope this information help get this issue resolved.
_________________
Date: Wed, 18 Aug 1999 15:53:41 -0700 COOLING SYSTEM PRESSURE MEASUREMENTS I finally had a chance to conduct what I call "dynamic" pressure
testing on the coolant system with the TriPoint AST using the
supplied OEM Mazda 0.9 kg/cm^2 (12.8 psi) pressure relief cap.
I did this by installing a temporary coolant line (replacing the
stock one) between the filler neck nipple and the AST nipple.
In this line was installed a calibrated pressure gauge that was
"T'"-ed into the temporary line. This allowed me to monitor the
pressure in the coolant system as it heated up, went through
various fan operation modes, and during engine hot-soak and
cooldown. Coolant temperature and pressure data was measured
and recorded during these tests.
The basic results are as follows:
During warmup, the coolant pressure increased relatively
rapidly upto approx. 15.4 psi maximum as the coolant expanded.
Coolant pressure remained at 15.2 ~15.4 psi until the cooling
fans ran for the first time @ 210 deg F (parking lights where on).
When the fans came on, the coolant pressure would drop to
approx. 6 psi at fan shutoff at ~195 deg F. Note: the temperature
monitor was a Type 'K' thermocouple mounted on the filler neck
housing near the ECU and fan switch sensors.
Parking lights where turned off to allow the coolant temperature
to go to ~228 deg F until the fans ran again. This caused the
pressure cap to vent alittle more coolant since the system had
not been this hot yet. Vent pressure was 15.3 psi. When the
fans would run, the coolant pressure would cycle between 15.0
and 8.5 psi.
Parking lights where again turned on to bring the fan cycling
back down to between 210 and 195 deg F. This caused the
coolant pressure to cycle between 8.0 and 3.2 psi. This make
sense, because more coolant was vented when allowed to go
to ~228 in the previous step. Once coolant has left the system,
it can not return until the cooling system cools enough to cause
a vacuum and pull coolant back from the overflow tank. This
starts to occur hours after engine shutdown as seen during the
hot-soak and cooldown portion of the test.
At one point, I enabled the A/C which caused the fans to run
continuously and bring the coolant temperature down to ~192 deg F.
This caused the coolant pressure to dip to a low 2.3 psi. Note: feel
the pressure in your AST hose sometime after the car has been hot
(city driving for awhile) and fans have ran awhile with A/C on. The
hose will have little pressure in it.
After the fan operations test, I shut the car down when it just
reached 228 deg F to get a max "hot soak". I was expecting the
coolant pressure to go back up to 15.4 psi and vent some more for
the first 20 minutes or so, but surprisingly the pressure started
dropping almost instantly. Reason for this is because the overall
"bulk" temperature of the system must drop, even though the filler
neck area of the engine was increasing. Good news, is that the
cooling system is not under full pressure during a hot soak.
Conclusions
The TriPoint AST vents slightly higher than the rated 0.9 (12.8
psi) cap, but not too far off. If it was more than 16 psi I would get
concerned. I did some more measurements of the TriPoint AST,
and found that the "effective pressure area" (area that the pressure
of the coolant pushes on the cap spring valve) is approx. 18 %
smaller than the stock AST. This causes more pressure to be
required to produce the same force on the valve spring. Note, my
TP AST had a 15.5 mm seat-to-seat dimension, which is within SAE
specs. Both the seat-to-seat dimension (determines relief valve
pre-load) and the effective pressure area play a very important role
in what pressure the cap will relieve pressure. BTW, 12.8 psi X
1.18 (18% increase) = 15.1 psi (close to what I saw). I also did
"static" pressure tests with air on the TP AST before doing the
"dynamic" pressure tests, that basically gave me the same ~15.0
psi vent measurement.
Running the dynamic tests also showed some interesting facts that
the coolant pressure in an FD (or any car with electric fans only) will
have large coolant pressure fluctuations as the bulk temperature of
the coolant system changes due to fan operations.
________________
From: Hoskinson, Jeff/EXEUG3 (jjhoskin@pscnet.com) Well, I finally bought an AST, based purely on the wisdom of the list. I
ended up buying one from from Perfomance Warehouse. I received it on
Tuesday or so. My first impression was, it looked OK, quality was OK, but
there were things to be desired.
Downside.
Upside.
It has a nicely CNC'd filler neck. It could be highly polished. The
weld look OK. It would probably work OK if the filler neck dimension was in
spec.
So I wrote Mr. Irvine, and he said that I was the first to complain (maybe
I am ultra picky, maybe I got a bad one?). He also said that his was better
quality than his competitors. He would charge me a 30% "restocking fee"
if I wanted to return it.
Any suggestions? So I am thinking of getting the "new and improved"
Tri-Point one now. I will sell this AST to anyone for $70, it is all Al,
sorta polished.
Date: Tue, 08 Feb 2000 15:51:28 -0800 SR Motorsports offers two radiators, the Mazdacomp which is
50% ($617) larger and their own version which is 100% larger ($695).
_______________
Date: Tue, 8 Feb 2000 15:37:51 -0600 Ray had these proprietary radiators
built to his specs. The quality is the same as the Mazda Comp units, but the
core is a full 2" compared to the 1 3/8" Mazda Comp piece.
The SRX7.com radiator is the thickest core unit on the market. For full
efficiency, be sure to block any openings in your ducting to force all the
air through the radiator. Many people overlook this simple trick.
_______________
Date: Thu, 30 Mar 2000 22:41:25 -0700 (MST) There's been some interest in info about the SR Ultimate radiator,
here's my $.02, I put mine in about 3 weeks ago.
Absolutely no fitment problems with the radiator itself, other than
bending the radiator support tabs below (really its no big deal, took 2
mins with a pair of pliers). Very easy to install, took me 2.5 hrs (and
I'm not a fast mechanic) including removal of the old radiator. Overall,
I'm very impressed with the quality of the radiator.
The only place I had slight fitment
problems are the I/C and intake. I have the M2 intake and the M2 large
I/C. The intake is pretty easy, you just have to bend one of the tabs at
the bottom so it goes around the fan bracket instead of inside it.
The IC is a bit tougher. It's not the I/C that causes the problem but rather
the ducting. With the increased depth on the bigger rad., the ducting
stuck up too far to allow the hood to close properly. I ended up
trimming the duct to allow it to press downward against the I/C when the
hood closes. That, and I now carry my hood prop rod in my trunk:-).
I don't know if this would also apply to the medium I/C, but I would think
so since they are such similar designs. If I made it sound complicated, I didn't
mean to, it really wasn't that bad.
I've got some
pics of all
this stuff on my site. Let me know if there are any other Q's.
__________________
Date: Mon, 3 Apr 2000 18:59:01 -0400 I recall someone noted the extra 1 inch thickness offset went up, not down.
Fine for the SR hood-hugger IC, but not so good for other brand large stock
mounts, esp the ducting.
PF says healthy stock rad is adequate ..... mabe in perfect shape. The
original mazda comp was 1.38 vs 1 inch stock core, but was narrower and had
less height, so core volume was only about 25% bigger.
What is needed is 1.38 to 1.5 inch core, with front area same as stock, and
all offset downward. Any bigger is overkill, imho.
__________________
Date: Sat, 11 Sep 1999 09:34:39 -0500 For you folks looking for replacement radiators... Ray Lochhead at SR
Motorsports (www.shaneracing.com) has the MCP unit listed at $615. You
might want to check that out.
I got mine from MCP direct and had no fitment problems other than a
little snip of the side piece. It was so trivial, I wouldn't call it a
problem.
_________________
Date: Thu, 7 Jan 1999 19:07:51 -0500 Pettit Racing will have a 50% larger radiator for sale in a few weeks, it
will also cost less than the current 33% larger unit. Jeff informed me the
50% unit will retail for $600. Those interested should reserve one now
before all will be spoken for.
__________________
Sandy lists places to get aluminum radiators. --Steve
Date: Tue, 27 Jan 98 07:09:52 -0500 >I am looking for a racing aluminum radiator for my FD. Mazda Competition, Griffen Radiator (on WWW) and Fluidyne (on WWW). None
are inexpensive (ie. all are over $500). On the other hand, an engine
rebuild is far more costly. Best intermediate step is a separate water
temp guage which tells you actual operating temp (critical at road race type
track events).
_________________
Date: Fri, 1 May 1998 02:28:20 -0700 (PDT) Sandy was nice enough to instruct Mazda Comp to ship his $500+ radiator to
me...I think I will just have to keep it :)
Actually he had it sent to me so I could verify that my ducting would in
fact work with it.
I was a little dismayed to see that it is an almost exact copy of the
stock radiator. I was hoping they had increased the width of the radiator,
taking up the space normally occupied by foam, with core space. What they
did was replace the foam with a piece of aluminum. Its possible they had a
reason for this, and will find out in the morning, as I am planning on
fitting it in the car then.
I did pull my stock radiator out of storage, unbolt the fans, and got out
the dial calipers. The stock core is just about 1" thick, and the Mazda
Comp radiator core is 1.5" thick. The end tanks are physically 2" thick,
where the stock end tanks are 2" thick only at the crimp locations, and
about 1.6" thick elsewhere.
I personally will most likely have my own radiator fabricated which can
take advantage of the lack of an A/C condensor, PS lines, etc, but would
suggest that most people use the Mazda Comp one, as it's definately a large
step in the right direction.
________________
Date: Fri, 23 Apr 1999 17:40:58 -0400 (EDT) The Derrick Sport radiator from Cork Sport is just as good as the
Mazda-comp but costs less. I haven't recieved mine yet, but I've been told
it should bolt right up.
________________
Date: Thu, 24 Jun 1999 09:42:52 -0400 The newer MazdaComp radiator, from Anthony Woodford Racing, has contoured
endplates that tend to follow the edges of the frame rails better than the
previous model(s).
Despite the new design, I still put in vertical ducts on
either side of the radiator. This effectively keeps all intake air going
through the radiator, instead of leaking around the edges. It also helps to
get some of that foam weatherstrip from a home store and seal up the areas
that the vertical ducts (mine are plastic - so not rattling against the
radiator or chassis) don't seal.
I went a bit more extreme though, and
removed the PS and AC equipment, so no condenser and PS coil in front of the
radiator. I have a big hole in the engine bay that allows me to see the
steering rack and road beneath the car. The hot air from the MazdaComp
radiator spills into this area and exits the car.
Cooling temps with this
setup is 185-195, and at WOT climbs to 210 or so. I ran up to 210 degrees
on the dyno, w/ a small low-CFM fan blowing into the front of the car.
Pressing the AC button on the dash still activates the fans, so temps go
right back down to 195 at idle or in traffic too. Temps were measured using
an Autometer electrical H2O gauge.
________________
Date: Sun, 02 Apr 2000 19:46:37 -0700 I went to the International Auto Salon at the Fairplex in Pomona, CA
today. This event is a big car show with lots of both cars and vendors.
I was very impressed with the range of products and vendors.
* FLUIDYNE - a new radiator for
the FD is listed as being scheduled for
release in April 2000 in their catalog and price list. An FC radiator is
listed in the catalog for July 2000 release. I wish I would have talked
to them now, oops!
_________________
Date: Mon, 3 Apr 2000 21:47:29 EDT I just called Fluidyne and they will have a drop in radiator ready for 3rd
gens by the end of the month. List price will be about $530.00. I asked
about a possible group buy and he seemed to like the idea. Just another
option. Their number is 800-685-0123.
_________________
Date: Wed, 26 Mar 2003 09:50:06 -0500 Here is some actual rad data from a comparison I did a couple years ago
Stock rad - plastic end tanks, 1" thick, 54 core rows with 105 fins/foot of
core
MazdaSpeed - all aluminum, 1 1/2" thick, 54 core rows, 110 fins/foot of core
Koyo - all aluminum, 2" thick, 64 core rows, 112 fins/foot of core
From the above it should be clear that moderate improvments will occur when
going to the MazdaSpeed unit, everything else kept equal. Increasing
thickness of a rad helps but there are diminishing returns for increasing
thickness same as there are for increasing thickness of an IC or any other
exchanger. More core rows is better and a combo of more core row and
thickness is better yet. That's why the Koyo will cool the best. Fit
issues need to be considered- the 2" thick Koyo can cause issues with fans
and other stuff plus what has already been noted. The MazdaSpeed should
always be considered as a stock replacement because it gets rid of the issue
of failure of plastic end tanks- plastic isn't really a suitable material
for end tanks any more than it is for ICs- its only justification is that it
is cheap. The MazdaSpeed is prettier and a better fit.
But don't expect a rad to be a miracle cure for track use- it is not as many
of us know from experience. As W notes, sealing is more important. The 3rd
gen motor with thermostat in place is flow limited for cooling. Drilling a
few holes in the t-stat, an old trick, works well and allows me to keep my
T-78 running 15 lbs boost and an 8500 rpm shift point at 205 degrees or less
on even sweltering summer days on track. 190-200 is more usual. Mine is a
TRACK ONLY vehicle (fuel cell, full cage, etc) so if you want to consider
this for a street machine that sees a lot of track use, note the following.
Warmup time is increased a lot
In cold weather, operating temps may be so low that you will need to block
some airflow to the rad (I cannot get over 165 in winter track sessions
otherwise)
Kiss emissions control goodbye. The real reason for the 3rd gen operating
temps on a stock vehicle has to be emissions- no sane engine maker goes to
226 fan temps unless forced to. Cooler motors emit more unburned HC, all
else equal (which it rarely is)
Contrary to what has often been said, lower temp thermostats cannot and do
not reduce operating temps by the fact that they open at a lower temp. Once
a t-stat opens, that's the end of its contribution to temp control which is
a warmup function, not an in use, regulating one. Some low temp thermostats
I've seen have a larger volume opening (height of opening and cross section)
so allow more flow - that is very probably the reason why some see reduced
temps with them in use.
(My car) also has the CWC oil coolers and, as reported by others, oil temps
track water temps with that setup.
_______________
Date: Tue, 4 Apr 2000 14:48:44 -0400 Below is a quote I received last night from
www.radiatorwholesalers.com
for a stock replacement radiator for
my 93 Auto.
I was asking for a possible upgrade, but all they had was the
stock replacement. The part number is 2067 and the cost is $149.34 shipped
to your door. Keep in mind this quote is for an auto, but they probably
have one for the manual as well.
If you get a used one, have it cleaned thoroughly.
_______________
Date: Mon, 14 Feb 2000 20:41:59 -0800 The AT Cooler was integrated into
the radiator on my 93 auto. I installed the Shane Radiator and an
aftermarket AT cooler.
Date: Mon, 23 Feb 98 17:43 PST For anyone interested in replacing worn, aged, and/or petrified
radiator hoses, I have come across the following.
Pegasus Racing (800.688.6946) stocks SAMCO Silicon Radiator hoses
for 3rd Gen RX-7s. The 2 hose set is a direct replacment for the
upper and lower large radiator hoses. Cost is $155.00 for both. The
Pegasus part # is:
The catalog describes them as "Bright Blue silicon rubber construction
with 3-ply reinforcement...." Temperature rating is -50degrees C
to +200 degrees C.
________________
Date: Mon, 12 Mar 2001 09:51:26 -0800 Got mine from Summit Racing. It's a Goodridge/Samco silicone upper/lower rad
hose set:
Cost me $156. Mine's blue but I think it also came in
yellow and red. Last I've heard Goodridge/Samco is stopping production due
to the dwindling market for these things. BTW, my Summit part# is:
________________
Date: Thu, 11 Feb 1999 07:35:15 -0600 I'm about to order up the parts to replace all the pressurized coolant hoses
in the system. The only ones I'm not sure of are the two for the
turbocharger. I couldn't see these from the top and didn't have the time or
facilities to jack the car up (its still in storage). How hard are these
two to replace, and how much of the engine needs to be torn apart to get to
them?
I counted 13 hoses total. If I've missed any, let me know. I might have
the in & out mixed up, but that doesn't really matter.
____________________
Date: Wed, 17 May 2000 17:30:46 -0500 I don't know of anyone that offers a kit in the sense of getting a
discounted, bulk price, but you can easily see (and order) all of the hoses
off the mazdatrix website .
____________________
Date: Tue, 28 Mar 2000 22:40:04 -0500 While I have yet to ascertain the real reliability of them, the Coolfex hose
system is constructued from seamless corrugated copper tubing designed to
withstand high vibration, high pressure use.
The exterior is chrome plated
and it has aluminum end covers finished in aluminum or chrome, black or
gold. there is a lifetime wrranty, though i haven't read it. 2 foot hose
with chrome covers costs $170 and for 3 foot length, $205.
They also offer a
variety of heater hoses of the same construction and finishes. I'm
installing the radiator hose right now and will be installing any others that
I can soon. Their number is 203-265-3617.
Date: Thu, 13 Apr 2000 11:04:45 -0700 Basically this is the hose that runs from the water pump that supplies
coolant for the turbos. It is well known for splitting and desperately needs
to be changed. Especially on high mileage 93 cars such as mine. 94K and
going.
Mine cracked and made a big coolant explosion after I turned off the car in
January.
So for all you who haven't changed it yet. Now you know where it is. Go
change it before you pop.
You have to remove Air Pump to get to it.
(Ed.'s note: I linked to his web site so the picture shows up inline
here. Here is the original link:
http://members.xoom.com/diepat_rx7/rx7/boom/9.jpg
).
________________
Date: Sun, 9 May 1999 07:04:07 -0700 (PDT) I used purosil 10mm silicone hoses for the feed and return from the
turbos. also on the throttle and under the throttle body feeding to
the thermostat. I have this on since June 98 and it seems to be fine;
no hardening or cracking or swelling. The OEM I had on the turbos had
swollen up to three times its size and was ready to burst. I'll see
if the silicone line will hold up.
_________________
Date: Thu, 13 Jan 2000 17:43:55 -0500 Here is the info on the 3rd gen coolant hose kit:
Goodridge silicone radiator hose p/n GS53-Y
The Y in the part number is Yellow so substitute the Y with R for red...etc.
Summit Racing should be able to get them for you. I bought mine from a local
speedshop, B&B Performance (203)481-0366
__________________
Date: Wed, 05 Feb 2003 09:38:24 -0500 I replaced the turbo cooling hoses three years ago with Teflon Hose Assemblies
w/Stainless Steel Braided Covers, still holding strong! Here is my post from what
seems like centuries ago:
Due to the many requests pertaining to the Teflon Hose Assemblies with Stainless
Steel Braided Covers, the supplier and part numbers are as follows:
McMaster-Carr: (330)995-550 or http://www.mcmaster.com
Hose #52515k24 $4.53 per footClamp #54195k14 $4.40 per pack of 10 (marine grade)
Approximately one foot of hose is needed, but order 1.5 feet (little extra in case
you screw up the first hose like I did). Trace the new hose along your bloating hose
and cut the new hose about a half-inch shorter than OE hose. If one cuts the new
hose to the same length as the OE, you will NOT have enough space/room to manuver in
place. Trust me, this was the most difficult part of the job, real PITA. Before
installing the hose, place the hose clamps on the hose. This will save allot of
skin! Trying to maneuver the clamps in place in the when the hose is mounted is
extremely difficult. Just to be safe, install four clamps per hose. I found my
first time through (note I said first) that a clamp was over-tightened(oops). Once
the engine got up to temp the metal expanded (popping the clamp) thus spraying
coolant on the turbos. Being more careful the second time, all went well.
Here is a universal fit electric water pump:
http://www.daviescraig.com.au/
_________________
From: Steve Cirian Agreed in terms of entropy, but in the real world it might depend
more on how each was implemented. i.e.- maybe the alternator has less
friction and power loss than the mechanically-driven pump. (i.e.-
poorly designed mechanically-driven pump). Also, for the
mechanically-driven pump you are adding an additional pulley, and
more friction, plus a longer belt (i.e.- more rotating mass (kind
of)).
An electrical pump would be able to be driven at a constant speed
instead of varying with engine RPMs. Therefore it would require the
same energy regardless of engine speed, whereas the mechnical one would
rise in speed as RPMs rise and thus induce greater power loss to
overcome friction and to pump more water. (I know you would probably
want to pump more water at higher RPMs, but you may not need to do it
at a 1:1 ratio as forced by the mechanical drive. Does anyone know
if the electrical pumps can vary their RPMs, and is it tied to a
heat sensor of some sort?)
Also, if the electrical pump is mounted remotely, you would have
moved some heat away from the engine. This would help engine
efficiency.
The drag race engines probably use a magneto. (Or am I really dating myself here?) But I am
not sure if that powers anything except the ignition. The accessories could all be driven from a
battery. Almost any battery should have enough juice to power the water pump, fuel pump, etc.
for about 4 seconds :-)
_________________
water pump removal/replacement procedures.
________________
Date: Mon, 11 Oct 1999 22:13:00 -0400 See
http://robrobinette.com/water_pump.htm
for the water pump replacement how-to.
______________
Date: Fri, 8 Oct 1999 16:46:14 -0500 The seal between the engine and water pump is shot, as is the pump
mechanism. Only had about 25k miles on it - the pump was supposedly
replaced around 15k miles, about 40k miles now.
There is a kit that replaces the front water pump seal and the pump
mechanism, not the whole housing. Comes with the lower radiator hose,
pump, gasket, and coolant sensor. The Mazda parts person seemed upset that
I knew about such a thing without them having diagnosed a warranty repair.
Info below:
Date: Tue, 14 Jul 1998 10:18:00 -0500 You should be running a coolant mixture of 1 part antifreeze to 2 parts
distilled water plus a whole bottle of RED LINE WATER WETTER.
If your engine compartment is dirty then it should be completely GUNKed
when only warm and then washed down with soap and then rinsed. A clean engine
is a cooler engine.
If you have used tap water in the engine for extended periods of time;
then flush the cooling system first with aluminum safe cleaner, then
distilled water, then add the mixture.
My temps have been about 195 in steady traffic and up to 210 in stop and
go with the AC on during these hot days. The orig thermostat is still in.
______________
Date: Wed, 24 Mar 1999 23:04:28 -0600 I'd highly recommend Havoline's Extended Life antifreeze/coolant (orange
colored). This stuff is the way to go, and nothing compares to it. It is a
patent protected, silicate free formula. What this gets you is no silicate
"slime" in your cooling system, longer water pump seal life, the best
corrosion protection there is, and 5 year coolant life. GM puts it in
nearly all their new cars, and can justify the increased coolant price from
water pump warranty reduction alone.
If you do any racing or autocrossing, you probably want to run a mix to get
you to the freeze protection you require in your area. Extra antifreeze
reduces the heat capacity of the mixture. Otherwise, 50/50 mix should be
just fine, unless your cooing system is in very bad shape.
_______________
Date: Mon, 27 Mar 2000 18:56:52 -0500 He had an engine failure and found it attacked the O-rings, chewed them and
left alot of white crustation. I can't remember the mileage it took before he
tore the engine apart, but I recall he said it was within a period of 1 year
or so. The best source of coarse is Dave himself. Stop by their
site
and drop him a line.
He said it works great in
piston engines as the gaskets have shown to negative reaction to it and he
was able to see a few degrees drop in temp, but in rotary engines, the
O-rings are too fragile and sensative. Now please remember that this is
Dave's opinion and several factors could have resulted in the failure, ie it
is not a scientific experiment, but due to this he urged us to stay away
from Dexcool.
Before the subject comes up, I will go ahead and mention he
found no difference (atleast on the street) using Redline Water Wetter. His
comments were, it didn't help but didn't hurt anything either. His advice on
lowering engine temps is to bore out the cooling passages in the housings,
the idea is to keep it rough (ie don't go for a polished finish) to increase
the surface area the coolant is in contact with the housing. He found this
yields 8 to 10 degree difference. Of coarse there is also the obvious fact
that aftermarket radiators are the best cooling mod...
_________________
Date: Mon, 27 Mar 2000 21:21:42 EST Thanks for the heads-up Wael, but I'm still left wondering which type of
"orange coolant" was used in this engine.
I made sure to use the Havoline
Dex-Cool since it is a proven coolant and very safe on gaskets, etc...
BUT I
have heard of such problems with the Prestone long-life coolant, also orange.
Maybe I'll be my own "guinea pig" since my FD just turned 85k on the
original motor... and the orange coolant has already been in there two years
with no abnormalities noted.
_______________
Date: Tue, 28 Mar 2000 16:53:15 -0800 With the recent comments about the use of Dex-Cool antifreeze in the
rotary possibly causing damage, I decided to give Dave at KD Rotary a
call to get the "straight story". Dave was kind of the instigator of this
information during a tech seminar at KD Rotary just recently. Dave was
pleasant to talk to, and was willing to share the whole story with me. This
is a summary of what he had to say concerning the Dex-Cool.
The product in question was Havoline's Dex-Cool. It was not Prestone's
Extended Life antifreeze. Both are orange in color, and both are
phosphate and silicate free. Beyond that, who knows the "secret"
chemical composition of each. Its unknown what Prestone Extended will
do in a rotary. I've had it in my Toyota pickup (V6) for about a year, and
the guts of the radiator still look new (looking in the filler neck).
Dave said he has rebuilt hundreds, if not a thousand of rotary engines over
the years, and has come across three separate instances where the innards
of the engines where coated with a "white powdery coating". It seems to
cake up at places like seams on hose connections, etc. Also, the O-rings in
these engines where "chewed up". Hard to say if it was a chemical
degradation (doubt it), or erosion from the "white crude" being in the
coolant. In one instant, the motor was one he had rebuilt, then had to tear
down again about a year later, so he say the "before" and "after" results of
the use of Dex-Cool.
We tried to come up with theories why it only seems to occur when used
in a rotary engine. One comment was that every rotary engine on cold
startup will leak a small amount of combustion gas into the coolant system
to some degree. Its possible that the buildup of hydrocarbons in the
coolant may have some bearing. Also, especially in the [3], there is some
hot localized heat due to the turbo charger cooling loop. Plus, its unknown
if water-wetter was used, and if that had any bearing.
My theory is, if this is occurring in your rotary you should be able to open the
coolant system filler cap when the engine is stone cold, and see the white
crud inside the walls of the coolant passages.
Safety Note: Only open the filler cap when engine is completely cold. I don't
want anyone burned up on my account.
_________________
From: dave@KDR
Hey Mike...here are the three following reasons and opinions for what they
are worth...
The first time we had rebuilt an 87 Tll...the customer installed at home
with our help and we watched him fill it with dexcool (havoline) and
distilled water...six months later at the drags on a stock engine he spiked
at 18 lbs and blew it...so we tore down for him and the engine coolant ports
were completely corroded...and the coolant seals showed really excessive
corrosion...we were very suprised..he flushed the heater and rad...went back
to prestone..
The second was a Hayes rebuilt that came to us with 8 K on it..the 3mm were
done poorly and the engine failed..when we tore it down it was the
same...the Hayes coolant seals were pitted terrible and the white powder all
over the aluminum rotor housings...we asked the cust and he said he used
dexcool and distilled water...
The third was 93 that the customer changed to
dexcool at 55K miles...the engine had coolant seal failure at 71K...it was
the same as the other three as the coolant seals were destroyed...the engine
in this one was never beat..older gentleman who maintained it religously and
never over heated...all highway mileage...so now what...
While we believe
dexcool is a great product we believe they may be several reasons for this
issue that is not prevelant in piston engines...(I ran dexcool in my 626
with never an issue...191K)...
my opinions are this...
Hope this helps...holler if any issues or questions...thanks a
mill..dave@KDR
_________________
Date: Sun, 2 Apr 2000 23:42:41 -0500 I'm cc'ing the list on this to spread around what I know. I haven't been
following the list very closely for the last few months, but thanks for
prompting me on this issue. I won't get too in depth right now, but the
ONLY problem with Dex-cool is that it can cause some silicone seals to take
an accelerated compression set. The effect is further accelerated with high
heat (roughly, 280 degF is a point to begin worrying). This comes straight
from an applications engineer at Texaco (actually Equilon, the joint venture
of Texaco & Shell, I believe). This is the one and only negative side
effect of Dex-cool. FYI - there are 20 Million GM vehicles on the road with
factory fills of Dex-cool and silicone seals in the cooling system.
All ethylene glycol coolants cause silicone rubber to take a compression
set. All silicones are porous, and the coolant gets into the pours, somehow
reducing the rubber's resilience. Texaco's recent research suggests that
there is some sort of protection mechanism of silicone by silicates in
conventional coolants (Dex-cool is silicate free). However, one thing to
keep in mind is that most Japanese coolants are very low/no silicate
formulations, so the factory fill may have been a no silicate coolant to
start with.
Now the key questions we need to answer: are the inner coolant seals indeed
silicone rubber? Mazda USA tells me it is proprietary and won't say (side
note - I believe they did tell me that they are coated with Teflon, at least
on a 3rd gen. I called last summer and don't remember the conversation
precisely anymore). Of those that say, yes they are silicone, what evidence
do they have? Second - is the Mazda factory fill a low or no silicate
coolant?
I'll tell you that I worry way to much about my car, and loose too much
sleep over my worries. Even though my car shows no signs of leaking
o-rings, I still got a cooling system pressure tester for the weekend and
tested my car. As expected, it held pressure great for over 15 mins, no
leaks (although my cap is a bit weak - only holds about 10 psi). I've had
Dex-cool in my car for 11,000 miles (since July '98), with no Water Wetter
(which has a lot of silicates, defeating the purpose of Dex-cool. For those
that insist on using it, I'd try Diesel Water Wetter with has no silicates).
The one thing that worries me, is that I'd bet the inner o-rings live in
metal that routinely gets over 280 degF.
Even though I will be sacrificing some aluminum protection and heat
transfer, I'm switching back to conventional coolant - for now. My contact
at Equilon graciously offered to put some of the said seals in their
internal test if I'd send him one or two. Also, in about a month, we will
have a machine at work that can test polymers and tell you what they are
made of, including surface coatings. So, I need 2 - 3 new Mazda inner
coolant seals. I think they are around $18 ea. from a dealer. It would
sure be nice if someone out there would offer to take care of this and send
them to me. Since buying a tow vehicle to support my racing addiction, I
can barely afford a glass of water. The part number should be N326-10-B71A.
TIA!
________________
Date: Thu, 6 Apr 2000 17:26:59 -0700 As far as ethylene glycol (EG) interaction with silicon
o-rings, I would bet there is no concern here. Almost every
modern engine in the world today has some type of
rubber parts (o-rings, hoses, etc.), so I'm confident that
EG is safe for these materials.
Recommendation is to not use propylene glycol antifreezes.
There boiling point is lower than EG at the same temp
and pressure. They may be fine for a low performance car,
but not for the rotary. There is no known antifreeze that
I know of where you can run an unpressurized system.
If someone could invent that, they could get rich fast,
since keeping a cooling system under pressure requires
alot more design and materials effort than not.
IMHO, the best thing to do for a rotary is change the coolant
*every* year. The rotary engine has lots more combustion
blow-by (even with new o-rings) than a boinger, and this tends
to "poison" the coolant at a high rate. Plus, the way the
engine is designed, it is a virtual "electrolysis monster",
meaning there are alot of iron/aluminum contact areas in
the rotor housings/end and center housings. As the coolant
degrades with combustion poisoning, heat and age, these
areas tend to corrode first.
Editor's note: Mike Putnam and Derek Vanditmars have instruction
up on the San Diego club's web site on how to linearize the temp
gauge. The rest of the posts in this section probably do not need
to be read, since they are sort of the history leading up to this,
and Mike's page does a great job of explaining everything. --Steve
Date: Wed, 24 May 2000 08:01:36 PDT The instruction on how to linearize the third generation RX-7 temperature
gauge is available at:
http://www.geocities.com/sdrx7_club/technical.html.
_________________
From: "Drew" (drewm@earthlink.net) For those of you who don't know:
The FD cooling gauge is an idiot light with a needle. It doesn't move until
it is too late. The rotary o-ring seals are very heat sensitive, will shred
and require an engine rebuild. Accidental overheating is the #1 cause for FD
engine failure.
Matt Severson programmed an inline interpreter. This gauge will actually
move in relation to the engine temperature! On start up the needle will
sweep the entire range so you know the gauge is working.
There are two reading settings:
Implementation:
Problem:
We need the connectors from Sumitomo:
http://www.sws.co.jp/EWAB/PRD/FRM/FILE/02.htm
Does somebody have a resource for this? Sumitomo sells in blocks of several
thousand. But they do send out free samples in the 100-200 quantity range.
Matt has the p/n number, but he can't seem to get them to send the correct
samples.
__________________
From: Max Cooper (max@maxcooper.com)
Could one of these alternatives work?
___________________
Date: 16 Jan 00 16:51:08 EST Drew the part numbers are as follows:
The connectors are 14-way, so I need 14 terminals for each female and male
connector.
I'll try and get the web page back up. Something simple, and I'll send you
the address when I've got it up and running.
ps. Yes, it will control the fans by turning them on @ 198 degrees F. I will
incorparate the fan control as an option only, b/c it makes the circuit a
little more complex. It will turn the fans on @ Medium speed.
______________
Ideas:
Yes, but the PnP concept would be so much better. It doesn't cost much more,
just the connectors are hard to get. They have to be very available, but I
just don't know how to get them. Probably a quarter per peice.
No. AFWCT.
AFAIK Pettit and Tri-Point have both known about this project. But they
don't come forward, I suspect they are not really interested.
I'm thinking total production is about 25 units and not much more.
_________________
Date: 16 Jan 00 20:43:02 EST
From: Matthew Severson (m995856@netscape.net)
here is a webpage i threw together...
kind of rough... but oh well.
_________________
From: "Drew" (drewm@earthlink.net) Gotten about 5 more requests for info.
I thinking a total production run of 100 will sell without a problem, with
25 being the absolute minimum.
Suggestions for your webpage:
Remove the link for Chart1 as you have it displayed on the referring page.
Not that I want to steal your thunder. I just want the product and think it
will be good for the whole.
How much does it cost for a printed circuit board? Some people want to buy the minimum order from Sumitomo and just chalk up
the excess to overhead. Would this be reasonable?
One last thing: What makes you think you are an "amature" programmer. You
stuff looks damn good to me...and I'm a programmer (or at least used to be).
__________________
Date: Sun, 02 Apr 100 15:42:22 -0700 Sorry, no response yet. Thanks for pinging me, I should have followed
up sooner. I'll try something different. Which connector is this in
the schematics so can find it myself? I see the signal winding it's
way through C1-04, X-14, X15, X-18, and C1-01 - X-14 is the only 14
pin connector, so that must be it?
__________________
Date: Mon, 3 Apr 2000 20:21:57 -0700 This is to the person (Umesh?) who works one floor above Sumitomo's USA office.
The person you want to talk to is Mr. Jim Greenwalt, Components & Parts.
I got the "Connectors for Automobiles" catalog the other day from these
guys, and the cover letter indicated that this should be my first contact to
call.
[Mail me]
[To Lightning home]
[To my home page]
[Copyright Notice]
Radiator Cap
From: "Ulen, Robert S" (Robert.Ulen@PSS.Boeing.com)
From: NetBlazer
From: "Westbrook, Chuck"
Thermostat
From: "Firas Arabo"
Air Separation Tank (AST)
From: KELLEHKJ@ESVAX-MAIL.ES.DUPONT.COM
Sent: Monday, March 27, 2000 7:11 AM
From: "Steve Wynveen" (wynveen@ticon.net)
> function is handled at the AST and thus needs to be a pressure cap.
> Pressure caps in both places is fine, but a normal cap on the AST woulda
> mean excessive boiling.
>Well so far we have two failures of "bullet proof" aftermarket ASTs, an
>entire batch of incorrectly fabbed aftermarket ASTs, and countless OEM AST
>failures.
>I have yet to hear of complications arising from AST removal.
After going though all this turmoil, I have a rough
theory on what's been happening in my case. As the
engine ages, greater and greater amounts of air is
'blown-by' the coolant o-rings and into the coolant
system, especially under sustained boost (e.g. track
events). Once the engine is up-to-temp, it no longer
expells any coolant or air into the overflow, so this
air either settles in a high area (AST, filler neck)
or gets recirculated through the system. The filler
neck area can only hold a small amount of air before
the trapped air is fed back into the coolant system,
especially under high-rpm conditions. The AST
provides a larger area out of the main coolant flow
for this air to surface. Once the car is shut-off,
any air trapped in the cooling system rises to the
surface. If this air happens to be away from the
filler neck or AST, it will remain in the cooling
system and not be expelled the next time the engine is
warmed-up. The AST provides an area for this air to
pool to be expelled during the next warm-up cycle.
[/opinion]
From: dbeale (dbeale@harddata.com)
Subject: Re: (rx7) Re: [3] Super duty AST tanks, making a new batch.
From: "Mike Putnam" (mike_putnam@hotmail.com)
Subject: (rx7) Re: [3] Super duty AST tanks, making a new batch.
> If there is air in the system, and the AST has been eliminated, how does
> the air get out? Do you now have to periodically burp the system as a
> maintenance item (as you do after flushing or filling)?
> look very sturdy and well made. But the hoses running to / from would be
> the weak link.
> Any feedback on how people are faring after doing the elimination? Some
> people have been running w/o the AST for years now.
> If there is air in the system, and the AST has been eliminated, how does
> the air get out? Do you now have to periodically burp the system as a
> maintenance item (as you do after flushing or filling)?
MC> I do wonder sometimes why the car had one in stock form. Mazda did a lot of
MC> work to eliminate weight and unnecessary parts. They even moved the coils so
MC> the spark plug wires could be short and thus light. If the AST wasn't good
MC> for something, it would not have been there. My car seems to be fine without
MC> it, but these thoughts do nag me sometimes.
> I don't think localized boiling would be it.
> Boiling water makes water vapor(steam), not air.
> High school physics.
> As soon as the water vapor (steam) cools, it collapses
> right back to liquid again, leaving no bubbles.
> When the engine cools, there would be no bubbles because
> of any kind of boiling.
>
> I agree with another poster, there is trace combustion gas
> leakage past the O rings. The AST is designed to purge
> that ongoing process.
From: Brooks Weisblat
>separator tank kit on your FD. Does it really help prevent coolant
>leaking? Please let me know.
From: "Schloesser, Eric"
From: Sandy Linthicum (sandy_linthicum@mindspring.com)
From: Mark A
From: David Beale
From: "Ulen, Robert S"
From: dbeale (dbeale@harddata.com)
From: Dunder@aol.com
From: KAWalanski@aol.com
From: "Ulen, Robert S" (Robert.Ulen@PSS.Boeing.com)
From: "Ulen, Robert S" (Robert.Ulen@PSS.Boeing.com)
using TriPoint AST with OEM 0.9 Pressure Cap
Date: Friday, September 17, 1999 2:25 PM
Radiator
From: Hernan Hernandez (gargoil@flash.net)
From: "Brad.Barber" (Brad.Barber@alsformal.com)
From: RX7TT93_R1@webtv.net
From: "kevin kelleher" (kellehkj@earthlink.net)
From: brad barber (bradrx7@swbell.net)
From: Wael El-Dasher (wael.el-dasher@yale.edu)
From: "Linthicum, Sandy" (linthias@sandy-ntws.usps.gov)
>I know Pettit Racing sells it, but it's too expensive for me.
From: NetBlazer (netb@world.bc.ca)
From: Wael El-Dasher
From: "Ryan Schlagheck" (ryan.schlagheck@worldnet.att.net)
From: Max Cooper (max@maxcooper.com)
From: ErnieT327@aol.com
From: "Paul Winter" (pwinter@nc.rr.com)
From: "Buras, Keith" (Keith.Buras@sea.siemens.com)
>QUOTE FROM: WWW.RADIATOR WHOLESALERS.COM
>
>Hello there, and thank you for shopping with the #1 radiator store on the net.
>We are committed to delivering 100% fit, form and function 100% of the time.
>Here at Radiator Wholesalers we believe in giving our customers the BEST
>quality at the absolute lowest possible price, 100% of the time. We
>appreciate your business and hope that one of our 35,000 O.E.M. style
>radiators in stock will meet or exceed your demand. And remember all of our
>Radiators are BRAND NEW, MEETING ALL O.E.M. SPECIFICATIONS, with LIFETIME
>WARRANTIES and are SHIPPED FREE TO YOUR DOOR AT NO EXTRA CHARGE. (in the
>cont. U.S. only) .
>
>I have the stock replacement radiator for your car for only $149.34. Ask for
>part # p 2067 when ordering.
>
>And remember this radiator quoted above comes with a LIFETIME WARRANTY and
>is SHIPPED FREE of charge to your door. Also no tax if you are out of
>California.
>
>Thanks again, and we look forward to doing business,
>
>RADIATOR WHOLESALERS For orders & questions call
>1-916-362-4444 Or
>1-916-RADIATOR e-mail us: AllRadiators@aol.com
From: Stephen Weckesser (sweckess@pacbell.net)
Radiator Hoses
From: Mike_Rollins@optilink.dsccc.com
TCS23.
From: "Hedwig Poon" (hedwig.poon@encompass-tech.com)
GS53-Y
GDR-GS53-Y.
From: "Steve Wynveen" (wynveen@ticon.net)
N3A1-15-186A Upper radiator
N3A1-15-185A Lower radiator
N3A1-15-183A AST in
N3A1-15-184A AST out
N3A1-13-681 Throttle body in
N3A1-13-691 Throttle body out
N3A1-13-692A Throttle body out to water pump housing
N3A1-13-53X Turbocharger in
N3A1-13-54X Turbocharger out
FD01-61-211A Heater core in
FD01-61-214B Heater core in
FD01-61-212A Heater core out
FD01-61-213B Heater core out
From: MT Sales (sales@merimartechnologies.com)
From: Gordon Monsen (gmonsen@fast.net)
Turbo Coolant Hoses
From: "Diep, Anh T" (DIEPAT@sce.com)
From: khoi ta (ta_rex7@yahoo.com)
From: Wael El-Dasher (wael.el-dasher@efini.net)
> I contacted Pegasus and they only
> have kits for the 2nd gen turbo.
From: Lvesnw@aol.com
Subject: Re: (rx7) [3] Replacing Turbo cooling hoses
Water Pump
Date: Wed, 7 Jun 2000 03:13:45 +0200
From: "Bernd Kluesener" (bklues@syskonnect.pp.se)
Date: June 07, 2000
>I agree with Gary. Maybe not a significant loss, but via the laws of
>thermodynamics, going from mechanical to electrical and then back to
>mechanical will definitely be less eficient than just staying mechanical.
>If all the racers do use it, and it is for HP as opposed to some other
>performance/protection reason, then it could be something like the battery
>and the alternator are sharing the load, so that a charged battery before
>a race acts as a power supply during the race (assuming a race is short
>enough that the pump won't drain the battery and the alternator[/engine]
>will have to work to recharge it).
From: "Rob Robinette" (robinette2@home.com)
From: Steve Stover (sstover@MadisonResearch.com)
Subject: (rx7) [3] Coolant Leak - Waterpump? Update
Part No. N3Z1-15-S20
Bin 159
List $145.81
Net $116.65
Anti-freeze
From: "Westbrook, Chuck"
From: "Steve Wynveen"
From: Wael El-Dasher (wael.el-dasher@efini.net)
> When attending the Rotary seminar given by Dave at KD Rotary here in PA this
> past weekend. He specifically mentioned not to use Dexcool (orange colored)
> coolant. I forget the reason, may have been that it was bad for the
> o-rings.
From: MikeFD3S@aol.com
From: "Ulen, Robert S" (Robert.Ulen@PSS.Boeing.com)
From: "Steve Wynveen" (wynveen@ticon.net)
From: "Ulen, Robert S" (Robert.Ulen@PSS.Boeing.com)
Observed Temperatures
Ambient Temp
At idle
Cruise
Med. Traffic
Hard Driving
Mix (W/C)
Sensor Location
Mods
70-80
195
185
205
237
60/40
Water pump
Radiator, IC, intake, single turbo
60-70
210
195
220
NA
50/50
T'stat housing
Radiator, IC, CWC oil coolers
60-70
210
180
190
220
60/40
T'stat housing
None
60-70
200
190
200
230
100/0
T'stat housing
Radiator, IC, radiator ducting, street port
70-80
210
190
210
230
70/30
T'stat housing
None
60-70
200
180
200
NA
80/20
Stock location
Radiator, IC, intake
Average:
205
188
205
229.25
Stock Temperature Gauge Interpreter
From: "Mike Putnam" (mike_putnam@hotmail.com)
Subject: [3] Cooling Gauge Translator
Date: Sun, 16 Jan 2000 08:49:41 -0800
From: Matthew Severson (m995856@netscape.net)
Male connector
M(6249-1265)
Female connector
F(6248-5309)
Terminals
Male
M(8230-4492)
Female
F(8240-4882)
> 1) Require the purchaser to splice the wires together instead of using a
> connector.
> 2) Does Mazda sell the connectors as part of a sub-harness?
Date: Mon, 17 Jan 2000 08:42:54 -0800
How much does it cost for a connector set?
From: "Andrew R. Ghali" (andrewg@netcom.com)
From: "Derek Vanditmars" (dvandit@istar.ca)