Hello all,

After complaining about the water temp gauge not working, I have found out since then, that it was indeed working, just not moving much above the "C". So, I figured I would install a 195 degree thermostat and see where the gauge reads. I drove it three miles this morning to my local parts store, and in that short time, the needle had already gone past the 75% mark!

I checked under the hood for leaks, and although I did find one (I had not tightened the clamp on the upper hose enough, and water was dripping out.) It was not enough to cause a major loss of water. I drove home and for the most part, the needle stayed at about 30% of the gauge, until the last mile when it again went up to 75%.

It does not seem to go above that mark, so I am wondering if that is normal, or maybe the gauge is not working correctly. I have tightened all clamps, and bolts, and drained the water, and installed a 50/50 mix of coolant/water. I don't have the shroud on it, as it was broken and I removed it so it would not hit the fan.

Anyone else have a water temp gauge that runs at 75% all the time? Or should I remove that 195 stat and install a 180? The book says 195 is correct for this year, but I am leery of a gauge that only has a quarter inch to go before it is in the "H"

 

I kinda had the same problem. My temp. guage didnt work when i got my 76 truck, i checked and the sending unit was gone. so i replaced it and than the guage was in hot all the time. So i took the cluster apart and cleaned everything good, and all the grounds in the engine compartment.That helped alittle it reads about 75 to 80%. i put a mech. guage in and the hottest it has ever got is 195 deg. which is waht my thermostat is. Try cleaning all the grounds and making sure all the connections a clean. Let us know if it helps

 

When I got my truck my gauge always read low. Replaced sending unit and made no difference. I went with a mechanical autometer guage and installed a 195 t-stat and it runs anywhere between 190-200 degrees

 

That's normal ..not to worry

 

Thanks for the input. I will check the connections, and clean them. Also, it doesn't seem to be overheating, but the gauge moves from 75% to 100% and then back again. On the freeway with cold air going through the radiator it was showing 100% or overheating, however, I drove 16 miles with it "overheating" and nothing happened. No blown hoses, or leaks etc. So I am thinking the gauge is just not reading correclty.

Also, I had the heater fan on high with it "overheating" and barely got any warm air out of the heater. If it were overheating, I would think a lot more hot air would be forced into the cab.

 

check the connector to a sending unit for a "steady" pulse of power.

It must go :

Pulse.....pulse.....pulse.....pulse

not

Pulse................pulse.................pulse

If it is steady the gauge doesnt have time to move before the next pulse of power gets to it.

If it is slow..it can be adjusted.

The alterative is to replace the ICVR.

 

I think you had better start looking for a new shroud tho. When you get to the summer heat it will make a big difference in the way it cools. They are there for a good air flow, so you need to get one. Erv

 

Ok, will check the pulses when I get a chance, thanks for the info. As for the shroud, I will either fix the one I have and reinstall it, or just look for one in the junkyard. Won't need one for a few months yet. Barely gets over 50 these days, but will go over 100 in the summer months.

 

i am having a similar problem of my water temp gauge reading incorrect on my 1976 f250 it use to read hot all the time until i replaced the temp sender, it reads normal now but hot when i have my lights on , the instrument panel ground is good and water temperature is anywhere between 180 and 210 degrees all the time, does any one have an idea on what could be causing this i was thinking maybe instrument cluster voltage regulator but i haven't a clue

 

I know this is old, but how can you adjust this if it is slow? Thanks!

 

I'll suggest it might be nice to know your truck's operating temp putting aside (temporarily) possible issues with IVR, sending unit and gauge. A low cost mechanical temp gauge from the AP store will install in place of the factory sensor. I'd suggest you do that with temporary mounting of the gauge in cab if needed. The mechanical gauges are pretty reliable and will tell you what is going on with your temps.

Then sort out the factory electric gauge.

Coolant temps in the 190 - 205 range should be expected with factory T stat of around 195 degrees. In hot weather a bit more.

 

I checked the water temp with a aftermarket gauge and a Mr. Gasket thermocap (radiator cap). the system is working correctly, but the factory gauge is off. Can anyone tell me how to adjust the factory gauge? Thanks again!

 

The only thing I can think of doing is to check the gauge and or replace it. To check and or replace the sending unit (which is what I would do first). All of this assumes all of the electrical wiring is in good working order etc....

Keep in mind that an electrical gauge is an electrical gauge. I don’t trust/rely on them. Usually by the time they show somethings really wrong....it’s too late!

My automechanic teaches words from almost 40 years ago still ring in my head. If you value your vehicle put a mechanical reading gauge in it.

So I have a set of mechanical gauges in my truck. I still like everything working so I do have all my electrical gauges working as well.