I have a 300 6 in an F600. Engine overheated and cracked head. Replaced head, radiator, radiator cap and thermostat. Engine will run at idle approximately 15 minutes before it begins to get hot or 10 minutes while driving. There should be no reason for the overheating problem!!!!! Any suggestions????

 

Silly question, but is the thermostat put in facing the correct direction?

 

Did the water pump impeller separate from the shaft? It happens

 

Good point on the water pump. If the blades on the impeller have corroded, they won't move the coolant.

 

i would start looking towards the water pump. and i agree to make sure the t stat is facing the right way. copper pelat facing engine. other things iv ran into but may not apply to you, hoses weak and collapsing rev the engine and look at them top and bottom, fan spinning the right direction, standing in front of the truck you should feel no hot air blowing onto you, when you replaced the head and radiator all of the coolant was pretty much drained so when you filled it did you let it bleed the air out of the sys, thats important turn your heater on full blast on the hottest setting with the truck running and if you got no heat or very little heat you still got a ton of air in the sys. so ck those things out and let us know

 

My recent bout of overheating problems started suddenly. I pulled out the t-stat and watched the water in the radiator. It wasn't moving, and the engine seemed to be revving more freely than normal. (you get to really know the feel of an engine that you've been driving a half-million or so miles). Anyway, I pulled the pump and it had about half of one impeller blade. Everything else gone. I had assumed that the rust that wouldn't stay flushed away was from the freeze plugs that had recently opened up on me. I guess not. Anyway, I'd look at that right away. Also, if you find that this is the case, do a GOOD flush/reverse flush, etc. before that new radiator gets fouled! I've had real serious rust issues in the past with the old 300. Mostly from freeze plugs. That's why on this build I replaced EVERYTHING in the cooling system including the radiator, and installed brass freeze plugs.

 

you do have antifreeze also, right??? and those radiator flush chemicals that you buy in a little bottle do work....

 

My F150 Started to over heat when driving so I changed the thermostat and bled the coolant system now its sitting at 3/4 of the way (but not moving from there) on the temp gauge is that normal for it or what should I do?

 

You need a way to "know" what the coolant temp is when this happens.
It could be the gauge is flaking out or really be a cooling issue.
Once you know that we can look at how to fix it.
Dave ----