something not to rule out is your lower rad hose, due to the age of our vehicles. One simple check is once the engine is at operating temps, feel the lower rad hose for heat and unusual soft spots, this will help indicate weather your hose is seperating inside and restricting flow. What I've found from personal experience is that the more of a load you put on the engine, ie hard prolonged accelerations, or highway speeds will cause the engine to overheat, since the flow is restricted, your boiling the trapped water, causing your coolant system to overpressured and possibly simulates an airlock.
That is how I interpreted the bentley manual, I'm sure someone will have something to add or correct if I'm wrong.
no thats good of you to mention this... i've heard too that the lower hose can get really soft and actually collapse during high speed. this would give a cold rad but boilover the coolant.
i think coolant hoses are a very overlooked maintenance item on many cars...
Topic: Cooling problem (Read 3202 times)
