Water Temp Gauge Installation

Last updated: April 22, 1998

Date: Mon, 20 Apr 1998 08:38:45 -0700
From: Spencer Hutchings

The digital temp gauge I got is the one from Intelitronix. It is a 2" black face gauge with three red led's. It has a lead for hookup to the factory dimmer switch. Installation was as follows:

  1. Tap the supplied brass sensor all the way to the base with a 1/8 pipe tap.

  2. Pull the hex head plug from the TOP of the water filler neck. This plug is 3/8 NPT or darn close to it.

  3. Go to OSH and get a 1/8 to 3/8 sleeve.

  4. Cut sleeve to about 1/4" thickness and thread in the sensor.

> Got a couple of questions for you. Why did you decide to tap the sensor
> from the top rather than the fitting half way down on the filler neck?

I used the top because I still have my smog pump, it would not fit on the side.

> Also have you since found out what the exact size the plugs in the
> housing are?

The sizes I originally stated are correct. The filler neck seems to have 3/8 NPT plugs.


Date: Wed, 02 Sep 1998 15:11:37 -0700
From: Lou Young

This past weekend I started installing an Intellitronix water temp gauge and ran into some problems mounting the sensor. I hit Steve's site expecting to find a whole bunch of different options for mounting the sensor, but I've only found one. So I tried it. It didn't work. More on that later. It involved using the plug on top of the filler neck, but I remember a bunch of people mounting the sensor in other locations, one being the 'flat spot' on the filler neck. I can't find the messages referring to this. Could someone point me to some good information for mounting the sensor on the filler neck?

The guy who used the plug mentioned chopping some material off the bushing to make it shorter and using a die to thread the sender further to make the whole assembly even shorter. I believe this is an effort to make sure that you can still take the cap off the filler neck. I did both. But my bushing didn't seem to want to screw all the way into the plug whole, and even with the modified sender threads, the sender was still way too tall to not get in the way to the filler neck cap. If only they had put the plug hole an eight of an inch further away from the spout. Here's some other things that the guy didn't mention: 1) Remove the spout from the filler neck. There's no gasket to replace, just an o-ring. You can't screw the bushing in with the spout still attached. 2) Don't, under and circumstances, accidentally drop the sender down through the plug hole. You'll freak out, and then have to find a way to get it out.

On a side note, since I have everything install except for the sender, I rigged it up to measure under hood temps. It's located just behind my aftermarket airbox in the engine compartment. I'm seeing anywhere from 160 degrees to 215 degree underhood temps while driving. They're not as bad as I expected.


Date: Fri, 08 May 1998 08:03:58 -0700
From: Spencer Hutchings

(My gauge) reads about 184-205 in traffic around town with 70-80 outside temp.
185-190 on the freeway at 80 MPH
195 on the freeway at 130 MPH


Date: Tue, 27 Jan 98 13:15:49 -0500
From: "Linthicum, Sandy"

>I'm planning to add an AutoMeter mechanical water temp
>gauge when I have the rest of my cooling system apart soon.

>Also, the tubing is 6 ft long, which seems like it could
>be tight for mounting on the steering column. Has anyone
>had any problem with that length or is it better to go with
>the longer version?

6 ft is to short - you can probably stetch it to fit but it will be in the way and a pain in the a!! forever.. Return it and get the 12ft one.

>From previous posts its seems most people are taping a
>hole on the flat portion of the thermostat housing.
>Autometer makes a 3/8" NPT adapter which I will use.
>Any tips when locating and making this hole?

There is only one logical place for the hole. NPT is a tapered hold, tapped in aluminum alloy. Tapping Aluminum is tricky, so get the correct specialized/trick tapping lube for aluminum and take your time or have someone else do it for you. I would suggest covering the metal capulary tube from the sensor to meter with something (like rubber hose) to protect it from heat & abrasion.

If mounted like I did mine, the new guage will remain at 0(lowest) till the thermostat open and lets hot water start to circulate. Temps will also go way up when you shut off the engine and part (heat soak). Both normal.

Pay close attention if temps go over 230F, they then to exponentally go up very fast from here and you want to keep them under 240F at all costs.

In crusing traffic, just turning on the A/C starts the fan running on low and will drop temps on a hot day from the 225-230F mark to less than 200F in a few minutes.


Date: Thu, 07 May 1998 21:11:33 -0700
From: Smeagol

Thanks to all who replied on my Intellitronix water temp gauge questions. My problem did turn out to be the ground I was using. If you plan on installing this gauge, don't use a ground for the lights unless you want it to act really funny. I moved the ground to metal/frame and it behaved normally. I was also playing around with the dimmer wire on the Intellitronix and found out that the gauge only dims half way. They also confirmed this over the phone. You can set it up to either dim w/the dimmer switch slowly, or just click down to half dim when you turn on the lights. I opted for the second way since I rarely use my dimmer switch.

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