QuestionI have a 1997 Chevrolet c1500 4.3 liter truck.
I have replaced the heater core 4 times now in 6 months due to them leaking. I have replaced the flow control, radiater cap and the water pump. The antifreeze mixture looks good. But fro some reason only a few weeks after replacing the heater core ( factory parts ) it develops a leak in it. Any ideas?
AnswerI would pull the heater core and have it tested by a radiator shop to see WHERE EXACTLY it is leaking.
There is a possibility of faulty heater cores BUT 4 is highly unlikely.
I always pressure test my parts BEFORE I install them.
the ONLY possibility is that you are building up to much combustion pressure into the coolant system.
Are you POSITIVE that you have flushed out all the anti-freeze and are using the FACTRORY RECOMMENDED ANTI-FREEZE for the vehicle ?.
I would install a pressure tester in place of the radiator cap and monitor the pressure for a few hours.
I really don't have an EXACT answer for you except the above.
autohelp
