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Discussion Starter · #1 ·
Hey fellas,

My truck (in my sig) has been overheating.Previously my temp gauge would never make it past the 1/3 mark even in the most extreme conditions and now overheats after about 20 minutes of light driving under no load.Once my temp approaches the red zone, my coolant pukes out into the overflow bottle till its full and then starts flowing out onto the ground.Through all of this, I've come to find that my coolant system doesn't appear to pressurize.I can run my truck till my gauge hits the 3/4 mark and just twist my rad cap off and release zero pressure!Under the same conditions,I can leave the rad cap on and squeeze the top rad hose and push coolant freely into the overflow tank.I've tried 3 different rad caps, one of which is new with the same results.

One other thing that I should mention is that even when the temp gauge reads past the 3/4 mark, I can remove the rad cap and stick my finger into the coolant which is hot but I could keep my finger there all day.Also,my upper rad hose never seems to get really hot either.

Could my thermostat be an issue...perhaps a bad waterpump?Anyone have any ideas?Thanks.

Frank
 

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water in oil or anything ?? maybe the headgasket went and thats were your pressure is goin.......
 

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My guess is the water pump and replace the t-stat if yur doing the deed. Good luck
 

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when you pull the cap, does the radiator fluid look like its even moving??

You could start by replacing the thermostat....fairly inexpensive test.

Is your water pump leaking at all?
 

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I recently replaced my 'stat because the engine wouldn't heat up. I found a piece of rubber lodged in the stat and was holding it open. It seems there is some rubber in the assembly of the 'stat and it was coming apart. I know last summer it would get hot really quick when I was pulling the camper to the beach. In hindsight, I think it was due to the faulty thermostat.
 

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sounds like to me your thermostat is stuck shut. I would guess your water pump is fine since it is overflowing your overflow bottle.
 

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thermostat stuck closed or the impeller of your water pump is gone (yes the will erode BADLY if the cooling system is not looked after!)
 

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Discussion Starter · #8 ·
Ok, there's no oil in the coolant and no coolant in the oil.Today I removed the thermostat which took a beating during removal and I have to wait till tomorrow for my replacement to arrive.I'll keep you guys posted on the outcome.Thanks for all your input.

Frank
 

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Discussion Starter · #9 ·
Thanks guys for all your helpful responses.A $16 T-stat cured the problem.:thumbsup:

Frank
 
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