my truck at 210k miles got a new radiator (seeping at seams), thermostat, water pump (bearings shot, leaking), intake manifold (The crossover was leaking). It now has 227k miles. Oil leak in rear at head gasket by starter (bad head gasket?) It overheated the other day( blowing coolant out the expansion tank needle in the red) Replaced thermostat. Drove around for two full hours, seemed fine, Drove to work today it overheated ( same thing, blowing coolant needle pegged) didn't make it to work. There are no external leaks and its not putting steam or white smoke out the exhaust. I read somewhere that a blown head gasket could make the truck overheat, is that possible? What all could cause this problem? Any and all help would be greatly appreciated.

 

Have you checked your oil for water? Did you change hoses when you did pump and radiator. If so, were they quality? If the lower hose collapses, it will get hot. It will spew out the overflow ounce it gets so hot. If the radiator cap is not holding enough pressure it will get hot.

 

No water in the oil and the lower radiator hose is old. I felt the radiator and the only places its hot is from where the upper hose goes in straight down the side to the bottom and across the bottom tank to the lower hose, the rest of the core is barely warm to the touch. So now I'm thinking the radiator is clogged up not allowing it to cool enough and gradually getting to hot?

 

What kind of stat did you put in?

 

Easy way to tell if you're getting coolant flow is to warm the truck up to normal operating temp and try to grab the coolant send and return lines to the radiator (but be careful as they will be hot - not enough to burn quickly, but definitely hot). If one of the lines is cool to the touch and the other is hot, you're not getting proper coolant flow for some reason or another.

I had my van blow a head gasket and slowly dump exhaust into the coolant system. It literally forced the coolant out through the weakest link (in my case the reservoir) and filled up the coolant system with air. When it was cool, I took the radiator cap off and stuck my nose in there and took a whiff (be sure it's fully cold before opening up the radiator cap). Man, that smell about knocked me on my butt!!! If the smell doesn't make your nose shrivel back into your sinus cavity and smells like regular coolant, poke a flashlight down there and check for any oil, floaties, or weird looking stuff (anything other than coolant).

 

I just went through this on my sons Scion TC last year, it kept boiling the fluid from the res, It had blown the head gasket between the piston and the cooling jacket, it was very slight so the coolant wasn't getting into the piston but the compression from the cylinder was getting into the coolant, if you pull the head now and not overheat it anymore, you may get away with just a gasket change, too many more heat cycles and you're probably going to warp the head.

 

I would never pull heads with any significant mileage on them and pop them back on without flattening them out. At the very least, get them tested for flatness (or test them yourself if you've got the tools) to see if they're within spec, or close. There's nothing worse than popping the top end of the motor apart, replacing the head gasket, then blowing the new gasket and having to do it all over again just 3 months later. Don't ask me how I know, but I will give you a hint - it involved Harbor Freight (Pittsburgh) tools.