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Overheating

1577 Views 5 Replies 4 Participants Last post by  jebx
My truck has been overheating for about two weeks now. I did the whole radiator flush liquid and I have replaced my thermostat, but nothing helps. I can run at night, with the hetaer on, at like 55 mph and it is still running damn hot. I think this is also thinning out my oil so I have really low oil pressure. It's like 28. All I can figure is to get my radiator rodded, but I am leaving for service in a month and I have been advised to sell this truck instead of rebuild it. What do ya'll think.
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You need to verify that coolant is flowing through the system. Is the radiator plugged and not flowing water through it? Thermostat installed the right way? Is the thremostat opening?
I have a '90 Chevy 1500, the Cheyenne. It has 200k and a lot of problems. The 4.3 262 engine is in it. My father replaced the thermostat and if he put it in wrong there is no hope for anyone. I was thinking about running it without the thermostat in it for now just to see if that will help. I'm pretty sure the coolant is flowing. If I turn on the heater at the right time it will cool down a bit. Mostly it will cool dow if I go down a big hill and coast, but as soon as I go up the other side it heats up again. I think my radiator is just full of crap and the flow isn't enough, but I don't know how to fix that.
I had a problem with mine overheating and couldnt figure it out. Problem ended up being that mud was caked in the radiator and not allowing it to breath. So after getting the hose out and discovering just how much was in there it ran fine after that. Not sure if this truck has seen alot of mud splashed up but that was my problem so i figured it maybe something to look at if it sees alot of mud...
Beater Red said:
I have a '90 Chevy 1500, the Cheyenne. It has 200k and a lot of problems. The 4.3 262 engine is in it. My father replaced the thermostat and if he put it in wrong there is no hope for anyone. I was thinking about running it without the thermostat in it for now just to see if that will help. I'm pretty sure the coolant is flowing. If I turn on the heater at the right time it will cool down a bit. Mostly it will cool dow if I go down a big hill and coast, but as soon as I go up the other side it heats up again. I think my radiator is just full of crap and the flow isn't enough, but I don't know how to fix that.

If it is not too plugged flush, or recore, or new radiator. I would try flushing it personally. I am also wondering if this is the root cause of the knock you have posted in another thread. Most of the time if you have a knock it is a bad sign, and overheating it and oil pressure dropping is asking for a disaster. Once the damage is done it is too late most of the time.
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