QuestionQUESTION: Have a 56 T Bird. I have chronic overheating problems.
I have checked everthing. Cooling system is fine. Fan is on correctly and shrowd around Rad is on. Is Ok on Highway
but cant drive it around town. Will boil over waiting for a light.
ANSWER: What did the compression check reveal?
And as I always ask, the heater is not bypassed?
What temperature rated thermostat is in the engine?
Has the engine been modified (bored, cam, carb) to a higher horsepower?
---------- FOLLOW-UP ----------
QUESTION: Compression check done and good. Heater not bypassed. Have replaced several thermostats, and Engine (312) not modified.
AnswerThe only reason a car overheats in traffic but is okay on the highway is the additional air flow, both on the radiator and the engine itself. For all intense and purposes the water flow increase although the engine is running faster in nominal.
With this in mind and presuming no after market a/c or transmission cooler to alter the air flow, I would first check the actual temperature the engine is getting to, not trust the gauge.
I had a car that did this and it was the radiator cap letting water out at night (with engine off and cold).
WIth the water jacket full, I have seen an engine with a head gasket blown to the waterside actually pass a compression check. Does the water in your radiator surge up and down slightly with the engine running and the therm open?
