Temp Gauge Help

[Shep69 149]

Im trying to dial in my temp gauge as my voltage regulator behind my dash is adjustable. If the motor is at around 160 Deg were should the needle on the gauge normally sit.By adjusting the voltage reg I can set the needle at the desired spot. 

[Midlife 814]

My preference is to adjust the voltage regulator such that the gas gauge reads correct at 4 gallons full; that's the more important reading to be correct on the dial face.  From there, the oil pressure and water temperature needles follow the gas gauge adjustments.  Therefore, you have a new set-point when your engine is running at 160*. 

I'd recommend replacing the 160* thermostat with a 180*---it makes for a more efficiently running engine.

[Shep69 149]

55 minutes ago, Midlife said:

My preference is to adjust the voltage regulator such that the gas gauge reads correct at 4 gallons full; that's the more important reading to be correct on the dial face.  From there, the oil pressure and water temperature needles follow the gas gauge adjustments.  Therefore, you have a new set-point when your engine is running at 160*. 

I'd recommend replacing the 160* thermostat with a 180*---it makes for a more efficiently running engine.

Thanks Midlife. As my mustang isn’t mobile just yet but I can start the engine I thought I might be able to get the temp adjusted. I did try using an old fuel sender and earthing it out while moving the float up and down. I thought that I nailed it but when I started the motor and got it warm the temp and oil pressure gauges went off the scale. 

[det0326 179]

Put a 35 ohm resistor in series with the fuel sender wire to ground and adjust the regulator to get a fuel reading of half a tank. Assuming all your sender units temp, oil, and fuel are correct ohm range you should be good. 

[danno 128]

Another way to do it is to put the temp sensor in  some boiling water, and then you know it is 212 degrees.  Adjust the voltage so the needle is way at the high end of the "acceptable " range. Or as midlife suggested,  make sure you have exactly 4 gallons of gs in the tank and adjust it for "E" on the gas gauge.