overheating problem

[brazosriver]

I have a bb chevy engine that keeps overheating. I have cored the radiator, new water pump, shroud, and new coolant. Motor still keeps getting hot. I haven't got any water in oil so i don't think a cracked head is a problem..You guys have any other ideas that i might try..thanks, glen

[Hallett19]

sand in the block, water pickup clogged, a number of things.

[Fiat48]

This may be a "wheel" vehicle unless he has a closed cooling system in his boat.

[HalletDave]

Originally posted by brazosriver
I have a bb chevy engine that keeps overheating. I have cored the radiator, new water pump, shroud, and new coolant. Motor still keeps getting hot. I haven't got any water in oil so i don't think a cracked head is a problem..You guys have any other ideas that i might try..thanks, glen
What about the thermostat or the pressure cap?
You don't have coolant leaking from your heater core or the hoses running to the core do you?
Kind of hard to diagnose from where I'm sitting.:D

[brazosriver]

Halletdave, No my heater core or hoses are not leaking. I put a new radiator cap and thermostat in and it didn't help either. When i changed the antifreeze I didn't turn the heater on in the car. Do you think that there could be air there that is not letting water circulate properly ? I did forget to say this is in a 66 chevelle. My boat is running fine for the moment..thanks for any help..glen

[Infomaniac]

It's probably lean. Check the fuel lines, fuel filter, sock in the tank etc.
If it has really low gears (big RPM's), sometimes the water circulates too fast to cool off. A change of pulleys is the fix for that.
Dual electric fans also.

[Sleek26]

Do you have a fan clutch that might be bad??
Electric fan that isn't coming on?
Does it over heat at speed or in slow traffic or both?
Could the lower hose be collapsing when the pump really starts to pull a lot of water??

[brazosriver]

sleek26...Hey i didn't think about checking the hoses but i will. It runs the same temp as long as i'm moving down the road, but if it sits in traffic it gets hot and will start boiling antifreeze out the overflow..Thanks for the reply and if you think of anything else let me know..i'll check hoses and fan clutch tonight..glen