Fluid Change

Last updated: February 16, 1998

Engine Oil

Date: Mon, 1 Dec 1997 12:42:15 -0600
From: "O'Dell, Mark"

> The total oil capacity for a dry engine is 5.7 qts for an R1 and
> 5.2 for the standard cars. The oil pan is 4.1 qts. According to my
> 93 owners manual the change vol with filter is 3.7 qts. So it looks
> like without taking a lot of things apart we will always have around
> two quarts of oil left behind for an R1 and about 1.5 qts for non
> R1s.

The retained oil is due mostly to the oil coolers. Each oil cooler holds about 0.5 Qts of oil, which doesn't drain out when the car is turned off. Also, the oil lines to the oil coolers and between the oil coolers themselves also retain oil. The R1/R2 models have two coolers versus 1 cooler for all other models, hence they retain more oil.

The only way to drain this oil is to remove the plastic covers under each oil cooler, and disconnect the oil lines where they connect to the oil cooler. I don't recommend this however - the C-Clips that connect the oil lines are not meant to be re-used. And they are relatively expensive to replace each time (sigh). All-in-all, it's a pain in the butt!

Because of the volume of oil left in the engine/oil coolers, I have decided to now change my oil every 1000 miles (filter every 3000 miles). Also, the fuel dilution thing scares me a bit - assuming that the dilution is cumulative, changing every 1000 miles should keep the dilution low. Perhaps this fuel dilution *might be* causing apex seals to wear faster. Hence all the low compression problems and blown motors... (no flames please - I admit that this is pure speculation on my part with no scientific evidence to back it up).

It's really quite easy to just drain the 4 qts. of oil (that you can get out of it) and refill it every 1000 miles - it only takes a few minutes and only costs $4-$5 if you do it yourself. And you don't need to replace the oil filter every time, so you save time there. Sounds like cheap insurance to me!


I would imagine that you could disconnect the lines going into the oil coolers and add a drain fitting of some sort in-line. This would provide an easy means of draining the coolers every oil change. I have not gotten under the car and looked at it yet, however. --Steve


Dave has some info on a device that will suck the oil out through the dipstick tube, but this might not pull oil from the coolers. I am not sure about this since the take off points for the lines to the coolers may be higher than the point at which the device sucks from. But here it is. --Steve

Date: Mon, 1 Dec 1997 22:03:00 +0000
From: "David Lane"

Regarding a device for sucking oil out through the dip stick hole:

I do it two to three times a year....on the sail boat.

Since you can't lift the engine to drain the oil from the bottom of many sailboat auxiliary engines, dip stick sucking is the only choice.

Here is the procedure:

  1. Go to a boat supply store and buy a Par Utility Pump. This thing is about 12 inches long, with a handle on the top, and a brass body. It comes with a small hose for the bottom--to stick in the dip stick hole, and a large one for the top end--to go into your used oil container.
  2. Run the engine until the oil is hot enough to scald your hands. This will make it easier for it to flow through the little tube, and it will also make you wish you had gloves--since the brass is an excellent conductor of heat.
  3. Try to find some place to balance your used oil container so that it doesn't fall over as you pull on the pump handle. Expect to wait about 15 seconds between the time the handle is fully extended and the time the brass body of the pump fills. This will build your triceps, and will give the oil plenty of time to burn your hands. Alternate hands so the burning effect is even. Expect the job to take about 5 minutes of pumping.
  4. When the pump starts drawing air, remove the small tube from the dip stick hole. Watch it sling oil all over you and your nice clean engine since it tends to whip around like a wet noodle. If you grab the end to keep it still, you will get hot oil on your fingers.
  5. Remove the other hose from your used oil container, noting that it is full of hot oil, and the outside of the hose (having been near the bottom of the container) now has a nice coating of hot sludge on it. You can wipe the outside off, but oil will continue to drip from the inside. If you turn it upside down so that the inside oil runs back into the tube, the other tube--which by now has started dripping again-- will start to whip around. See #4.
  6. In a very quick and graceful move, grab some paper towels and try to catch the oil that is dripping from both tubes at the same time. Of course, you will have to let go of the pump to do this, and at least one of the tubes will come out at the pump end, giving you yet another dripping tube end to control, plus, of course, the open hole in the pump itself. In your effort to do three things with two hands, you will almost certainly find yourself knocking over the used oil container, dumping at least half of the oil on your engine, and into the bilge of......er......onto your garage floor.
  7. Grab the handle of the used oil container and try to minimize spillage. In doing so, you will certainly sling about a cup of hot oil out of the spout, and it will certainly land somewhere where a.) you can't get a rag in to clean it up or b.) there is exposed skin.
  8. In total frustration, grab the Par Utility Pump and hurl it as far from the car as possible. Avoid living things.
  9. Finish the job, clean up the floor. Wash your engine. Take a shower. Apply burn dressing. Treat yourself to some ice cream. In several days, the splotchy marks created by the hot oil on your skin will make you suspect you have skin cancer. The doctor will ask you if you own a sailboat. Tell him you were trying to suck the oil from the dip stick hole of your RX-7. Don't laugh when he asks to inspect your throat.

When you are done, call Victoria British, Ltd., and order one of their nifty little lever spigots to replace the drain plug on your oil tank. Next time, just jack the damn car up, loosen the oil filler cap and flip the lever.


Date: Sun, 5 Apr 1998 18:22:00 -0500
From: "Westbrook, Chuck"

While draining your oil, set the new oil filter upright and sitting on it's closed end. Fill up the filter with oil until it will not absorb any more. Just before installing it, drain out the oil that's filling the opening, then install it. This way the filter is almost full and will not take long for the pump to fill it completely.


Date: Fri, 19 Dec 97 14:33:49 -0500
From: "Linthicum, Sandy"

Previously I mention I had changed from Redline MTL to Amsoil Series 2000 75w90 in the tranny and that shifting suffered, particularly when cold.

Well, stupid me and my mechanic. There are two fill holes on the tranny, one a regular bolt and the other a T55 torex. The torex bolt is above the other one and was used to refill the tranny with the Amsoil 75w90. This is NOT the one to use. Using it to determine when the tranny is full results in overfilling the tranny by at least a quart and very hard shifting.

The Amsoil would probably have be fine if the tranny hadn't been overfilled. This torex bolt doesn't appear anywhere in the service manual and I havn't been able to fine out what it is for.

The tranny is now full of Redline MTL (naturally I we figured this out after the Amsoil was dumped!) and shifting is again excellent.

Hope this saves someone else a hassle. Using the proper fill hole the tranny takes exactly 2.5 quarts, just as spec'ed.


Date: Sat, 15 May 1999 18:30:54 -0400
From: James Forbis (james@forbisassoc.com)

I went to the local parts store and bought about 4 feet if 3/8 fuel line. Snaked the line down to the tranny, stuck the line in the fill hole, and poured the lube in. Its kinda thick and takes a while but it works..


Date: Sat, 15 May 1999 20:45:30 EDT
From: ShelbyDk@aol.com

This is easy w/the right tool. Go to your local hardware/auto parts store and ask for an "oil suction gun." It has a hose on the end of it and works much like a big turkey baster (only better) be sure to keep it handy to do the rear differential too!!


Date: Sun, 18 Jan 1998 11:43:03 EST

For those interested in changing the diff fluid, the fill plug is 23mm and drain plug is 24mm. You'll need a 3 inch extender for the top plug unless you have a really flat ratchet.

I'm also interested in different ways of how some of you filled your diff as I ended up with about 1/2 quart on the garage floor! It's hard getting the redline higher than the drain plug plus pour it downward. I had to use a bendable skinny funnel barely wide enough for 75w90 to flow through. Those of us not lucky enough to have a vacuum pump/hose would like some tips.


Date: Sun, 18 Jan 1998 13:28:04 -0500
From: "Alan H. Beder"

Buy the pump that looks like a big syringe with a flexible hose. I don't think it costs more than $10. Sears and most autoparts stores will have them.

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