as topic says, how do i bleed the air out of cooling system ? or i should simply do a powerflush ?please advise. also this 03 civic with 30k miles. never changed coolant since its a longlasting coolatn from the factory. please tell me your opinion.
thanks in advance

 

What makes you think that there's air in the system?

 

because i hear water trying to mov through the pipes from the glove compartment side. and when i accelrate, i hear bubbling sound from the engine. i belive its an air in the cooling system, Am i right ?

 

Have you checked the coolant level? Any noticable leaks?

Yes, you're probably right that it is air in the system.

 

no no leaks or anything. how can air get in ?

 

Let you car sit and idle with your radiator cap off. Turn the heat on full blast. Let it run until no more bubbles come out of the radiator nozzle. Put the cap back on.

 

Lots of ways, could be a bad radiator cap letting coolant spill under pressure. Worse case would probably be a head gasket.

The level wasn't low at all? Take off the radiator cap, turn the heat on high, and let the car idle. While idling, the system should bleed itself. It usually takes a while though.

 

I may be wrong but I think that service centers use a tall funnel to fill the radiator that probably seals tight into the radiator filler neck. Not sure how to explain this other than to say the top of the radiator filler neck is lower than the highest point of the cooling system path.

 

Turn the dial to heat but dont turn the fan on, let the car idle with the cap off until it gets to normal operating temp, which is when the fan kicks on.

Jim

 

It is irrelevant as to wether or not the fan is on.

I like to keep it on to make sure that the heat is hot.

 

try to jack the front of the vehicle up, turn the heat on high and circulate, and rev the car around 2000rpms till no bubbles are present and your heat stays hot at idle.

 

I've never had a problem with just leaving the radiator cap off and having the heat to full hot. Raising the front end is a good suggestion too.

 

open the air bleed screw on the head. It's like a 10mm or 12mm. Its the highest spot in the cooling system.