its time to work on the subie
my current situation
1) car drives in low speeds up to 60km or 2.5k rpm fine and can idle for 1 hour without any overheating
2) if i rev the engine above 3k RPM there is bubbling in the radiator fluid. If its idling then there are tiny micro bubbles can barely be seen
3) water used to evaporate from radiator but when keeping an eye on the RPM and keeping it below 3k it stays there
the car is a 1990/1991 and has a 2.2 engine with 16 Valves.
Questions
1 i do not see any smoke in back or leaking on the engine. no white goo on the dipstick or oil cap. How do i DIY diagnose it as a head gasket forsure?
even though i do see a bit of an oily glow on the surface of the rad water
2. is there a way to check the water pump for failing? it used to leak from the bottom sip hole but after using bar soap it doesnt do it anymore.
and there is no squeeking noise from the pully.
3.is it worth trying some liquid sealant that can seal small head gasket cracks??? any recommendation for liquid seals?
thanks for all the help and support