Hey, my trucks motor was rebuilt and has a one year old radiator and a new thermostat. When I start the truck the temp guage gradually goes to the middle of the guage and then sometimes it shoots up higher and recently it did this and i tried to floor it (heater was on) and it went just a bit under the top green line and then went back down to the middle. Does this sound like an overheating issue or a faulty guage? Could the truck really cool itself that fast?

 

they have a temp overshoot issue. do a search on here for more info. also if you used an aftermarket t-stat did you test it? a lot of em tend to be faulty from the box.

 

I was thinking that but wouldnt the heater be blowing cold air if the tstat was faulty?

 

no the idea is that it would be opening at too high a temp or sticking shut. the heater will still heat up, just the coolant wont be able to go into the rad until it finally opens.

Its easy enough to pull it, and boil it in a pot of water with a thermometer to test that it opens and closes at the right temp

 

hmm il check it out
thanks

 

Hows the coolant in the rad?

I had the same problem with the blowing cold air thing, and I also thought Tstat right away. But turns out coolant was escaping thru the rad cap (I hope)

 

the coolant is brand new and the rad is filled

 

When you replaced the radiator, did you buy a new radiator cap or transfer the old cap on to the new radiator?

 

TSB: 029032787 22R-E Engine Temperature Overshoot:
- http://www.4crawler.com/4x4/CheapTri...tml#Thermostat