ok i posted about a week ago that i was having cooling problems and im still having them so i need you guys's help to figure out the problem. the truck will run fine at low rpm's, but as soon as i run it hard and it gets a little warm, it will not cool back down. i replaced the thermostat with a brand new one, i also replaced the water pump. i took my electric fans off and put back the stock fan with a new clutch. i also took my underdrive pulleys off, but with no luck. i replaced the radiator hoses just in case, but with no luck either. i put plenty of rvt on all the gaskets, and there are absolutely no coolant leaks. i replaced the radiator cap (in case it wasnt holding in the right amout of pressure). im gonna go get a coolant flush next weekend when i get a chance, bit if that doesnt help then what else could it be? please help, im completely out of ideas, thanks...

 

If it gets real bad, turn on your heater, open all your windows, this will take the heat from the engine for temperary relief

 

I would check my spark plugs, see if one has a white insulator. It sounds to me like you have a blown head gasket. *ouch*

 

Could be a blockage in the radiator or heater core that won't let coolant circulate properly. Maybe you could find a store near you that sells Redline Water Wetter. That should cool it down a few degrees. Another thing to check, is the coolant temp sensor and the gauge working properly? Maybe the gauge is showing hot but the temp is normal?

-Jon

 

sounds to me like ( no offense ) the T stat is in backwards .

 

no offense taken. that was my first thought too when i first replaced the thermostat, but i checked it and it was in perfectly fine. i actually replaced the thermostat three times, thinking maybe i had a faulty one (i even put it in backwards once just to make sure i was putting it in the right way). i know the temp gauge is working because you can see the coolant in the reserve boiling up when it reads hot, and the first time it happened i let it get really hot up to the point where the engine began to smoke a bit. what would be the symptoms of a blown head gasket? im gonna check the plugs next time im at home. if the radiator or any part is clogged, im HOPING that the coolant flush will take care of that. so here's what i've ruled out so far:

-thermostat in backwards
-faulty thermostat (ive installed 3 different ones with no luck)
-water pump
-faulty hoses
-any type of leak

what else should i check out? please help, im running out of ideas, thanks!

 

well, you will get the overheat, hard start, runs rough,white smoke, and the miscolored spark plug. You might get all or just some of these symptoms. If you are going to remove the plugs, be thankful you don't have a new 4.6 or 5.4 engine.

 

ohh i am, removing my plugs takes about 20 minutes (without any bloody knuckles)

 

By what method are you determining that it is in fact overheating?

If it is, you need a new radiator, but still, answer my first question. Please.

Take care,
-Chris

 

well, first the temperature gauge begins to climb ONLY after i run it pretty hard (when i let the rpm's go higher between shifts than i do normally). im assumming the temperature gauge is correct because the first time it overheated the whole engine began to smoke (there was smoke coming from the hood and so i had to park and pop the hood and let it cool). i havent let it get that hot since so it hasn't smoked that bad, but whenever it gets a littel warm now the coolant begins to boil. if you take the cap off of the coolant reservoir, hte cloud of steam that comes out is so thick that you cant see a damn thing. last time i drove it it overheated again and so i parked it for about 20 to let it cool then i wrapped a big towel around the radiator cap and opened the cap, but as soon as i turned the cap a little bit, all the hot coolant came up through there. am i wrong in thinking its really overheating? is the problem somehwere else? if not, then ill go ahead and change the radiator. i can get one pretty cheap from a friend of mine. thanks for the help!

 

You can check if your radiator is working properly by checking the temperature inlet-outlet. If there is a drastic temperature difference, the coolant does not flow through it properly (that was a tip from a radiator guy when my Volvo overheated. It turned out to be a cracked head).

 

Yeah, if you have an infrared pyrometer you can check the temps at various places throughout the cooling system. Just be careful overheating it, i wouldn't recommend driving it till you figure out the problem. If it's not a head or head gasket problem right now it could be if you overheat it too many times.

-Jon

 

Boy, that sure does sound alot like a head gasket. Do you not have a puke tank for the radiator (overflow tank)? That should keep it self contained, but you have a much more serious problem. You need to find someone with a cooling system pressure tester, and test your cooling system. Air is getting in somewhere. Try CarQuest. I'm pretty sure thay loan tools like that.

Take care,
-Chris

 

you mean the coolant reservoir? you should see it after i drive the truck, the coolant is BOILING in there, and usually overflows after i park it. a mechanic friend of mine told me he can check out the cooling system pressure for me so im gonna take ot over to him as soon as i can. thanks for the replies.

 

Let me clarify what he's going to be doing. he's going to attach a hand pump to the radiator, where the cap goes. After he pumps it up, he will watch the gauge on it to see how fast it falls. It shouldn't fall at all, but if it does, you need to start looking for where it is the pressure is going. Have him pressure test your cap, too. Even if it's new, that doesn't mean it's right. trust me.

Take care,
-Chris