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Water temp & oil gauge install


This article describes how to install a water temp & oil pressure gauge install


Most people rely on the stock gauges to measure water temp and oil pressure.
While the stock gauges provide with a certain measure of its state, they are not accurate at all.

A stock water temp gauge reading in the N-O-R range, could be giving you temp data over a wide range most probably from 190 to 230 range, not accurate at all.

The stock Oil pressure gauge is worse, it really has just one state, pressure and NO pressure.

The only CURE to this problem is to install some aftermarket gauges. Autometer has some nice gauges for measuring any relevant data; water temp, boost, vacuum, oil pressure, etc.

Gauges come in 2 types. Mechanical and Electrical.

Mechanical gauges relay on ANALOG data, that is, direct contact to the source of data; Example: an oil pressure gauge is connected DIRECTLY to the block by means of a capillary tube that sends OIL pressure to the gauge.

Electric Gauges use a SENDER that converts an ANALOG signal to an Electrical one; Example: an oil pressure sender is installed in the block; the oil pressure applied to the sender is converted to an electric voltage which is fed to the gauge by means of a wire.

Mechanical Gauges are more precise, but also harder to install, but don't get scared about it, it is really not that hard.

HOW TO GUIDE (Mechanical Gauges)

I installed 2 Mech. gauges:

  • 2" Oil Pressure

  • 2" Water Temperature

List of material needed:

  • 1 Piece of Acrylic, plastic or aluminum sheet (2,-3 mm thick)

  • Vinyl sheet

  • 3M spray glue

  • Gauges

  • Teflon Tape


I first choose a location to mount the gauges, since I have no CD player; I decided the best place was under the Stereo.

You can also buy a gauge pod to mount under the dash, or an A pillar pod. Most pods come in 1, 2 and 3 gauge versions.

In order to install there I had to create a Gauge Pod, I used a piece of Acrylic and some black vinyl to cover it and have a stock look. I drilled two 2" inch holes to accommodate the gauges (could easily fit 3).
After drilling the holes I glued the black vinyl to the acrylic pod using 3M spray glue (Home Mart or Home Depot).

To fit the vinyl to the circumference of the holes, I performed 5 series of radius cuts to it, and then glued each slice to the pod. Make sure you leave about 1-2 mm un-cut to take into account the acrylic thickness.

The next step is to install the gauges in the pod to make sure everything fits ok in the dash.

GAUGE Connections (5.0 engine, 4.6L similar)

The water temp gauge is the easiest to install, just route the copper tubing from the gauge under the dash and out of the firewall, and into the engine. I routed mine between the upper and lower intakes.

Be careful not to bend the copper tube, it can easily get broken.

Remove the factory sending unit located on the front right side of the lower manifold (your right side facing engine) and screw the water temp send unit. Make sure you wrap the connector with Teflon tape to avoid leaks.


* If you want to keep the stock gauge working there is a place to connect the stock sending unit in the rear left side of the lower manifold.

The Oil Pressure Gauge is the hardest to install, but it just takes a little more time than the water gauge.

Locate and remove the stock sending unit, it is located at the front of the block, just a few inches above the oil filter.

Route the capillary tube in the same way you routed the water temp copper tube.

Now, follow the manufacturers' instructions to attach the capillary tube to the gauge and engine adapter.
I used sensor safe silicone sealant just to make sure there are no leaks in the gauge.

Now that the tube is connected at both sides, place a used piece of cloth under the oil gauge, you want to make sure there are no leaks (or else ruin your carpet). Start the engine and keep it running until the capillary tube is filled with oil.

Got leaks? Check all connections.

You could also buy BRAIDED LINE or Copper tube to replace the Nylon tube supplied by Autometer. It costs more but might be worth it. The nylon tube might not last long under high temperature. I insulated mine using a piece of brake line hose.

Almost done

Now locate a source of current to connect the gauge lights, I selected the gauge cluster illumination wire that goes out of the fuse box. Route a wire to the gauges and connect to the RED wires.

Connect the BLACK gauges wire to a good ground.


hope this helps


Article by: GTRaptor Profile | E-Mail

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