Hi. I've got a 53 plate sti that's covered 65000 miles with very extensive service history. Today I was under bonnet and though I cod see damp on top of header tank. ( metal tank in o/s ). My heater works perfect. Temp gauge is perfect. Top and bottom hoses warm. Coolant levels on both tanks perfect. I took rad cap off and with engine runing on over run could see very small bubbles. I mean tiny then they vanished. I reved car tk 2600 for bout 30 secs then lifted off then water level slight ran out of header tank. Does this all sound normal and am I panicking. Car is totally standard bar cat back exhaust. Car is driving perfect.

Hope I'm just being over cautious. Thanks

 

thats normal its how you bleed the cooling system

 

Thanks mate :-). Was in a panic to be honest.

 

take the cap off when cold and top up with coolant, then let the engine tick over till warm, the air bubbles will stop after a while .

then the systems is bled and dont rev it

 

Do u mean the header tank or the plastic one at front mate

 

header tank next to intercooler

 

Thanks again mate. Is there any reason there would be count around the cap on header tank. Thought it may be weather related as minus 2 up here last few days