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bleeding air from cooling system

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help !!!!!!!!!!!!!!!!!! how do you bleed air from the cooling system , i read it a few months ago but cant seem to find it . my car has the famouse water noise in the dash board i have a legacy 2.5 please help...........:banana:

Idle engine with the rad cap off until the fan comes on. Top off, mount cap again.

Setright has nailed it that is the way I do it and it works fine.

Idle engine with the rad cap off until the fan comes on. Top off, mount cap again.

thats how i do it, the other method suggests putting the front of the car on ramps to bleed it.

 

nipper

  • Author

i jacked up the front and did as setright said , a heap of bubbles came out large and small and when i turned the car off a few more went in to the over flow bottle is that normal leaving it over night to cool any other advise

When you mount the rad cap, there will be a delay before the cooling system builds enough pressure to push expanding fluid past the rad cap. Once it does, it WILL cause bubbles in the tank because the hose connecting them is empty to start with.

 

But why did it happen after you switched off the engine?

 

Fit a new, genuine cap before going further.

Don't forget to milk the upper radiator hose to squish the air along with all the useful advice you already received above.

I'm not a fan of squeezing the hoses, you are just as likely to suck air back in.

 

If your rad has a bleeder screw that should be out too, of course.

Biltz, thanks for that great link. I can't tell you how much I dislike slowly pouring coolant into a Subaru just to avoid those darn "air pockets". Have you used that Lisle coolant thingy? Do you like it?

:headbang: am i just incredible lucky? i have never had an airpocket in the cooling systems, and ive changed raditaors, flushed em, changed T-stats and waterpumps, never an issue.

 

nipper

:headbang: am i just incredible lucky? i have never had an airpocket in the cooling systems, and ive changed raditaors, flushed em, changed T-stats and waterpumps, never an issue.

 

nipper

 

i'm getting ready to flush mine (99 OBW 2.5 DOHC) i can't decide if i should just flush with water, or use one of the products available. i've got a net T-stat, so i'll flush it with it out. the headgaskets have been done so i was thinking of using comercial flush. what do you think?

when i'm done i'll replace with antifreeze and distilled water.

i'm getting ready to flush mine (99 OBW 2.5 DOHC) i can't decide if i should just flush with water, or use one of the products available. i've got a net T-stat, so i'll flush it with it out. the headgaskets have been done so i was thinking of using comercial flush. what do you think?

when i'm done i'll replace with antifreeze and distilled water.

 

 

Flush with water. DO NOT use a product. if you been flushing regularly there is no need for it. FLush products can remove everything holding your system together.

 

nipper

Flush with water. DO NOT use a product. if you been flushing regularly there is no need for it. FLush products can remove everything holding your system together.

 

nipper

well...i just got the car with 70k on it, the heater doesn't seem to put out like it should, i thought maybe someone had put the "treatment" in it so i was going to use a product to try and clean it out. HG's have been done, i figured i'd be okay with something recommended for aluminum. but, water it is....thanx

well...i just got the car with 70k on it, the heater doesn't seem to put out like it should, i thought maybe someone had put the "treatment" in it so i was going to use a product to try and clean it out. HG's have been done, i figured i'd be okay with something recommended for aluminum. but, water it is....thanx

 

two words "reverse flush" . i flush via the heater hose (get a kit). Its amazing what comes out. DId you use a OE t-stat? The pipes in the heater core are huge compared to the radiator, so heater cores dont clog as easily as they used too, if ever.

 

nipper

Have you used that Lisle coolant thingy? Do you like it?
Oh yeah man, several times. It's just cheap plastic crap but it works really well.

 

I actually learned about that device on USMB about 2 years back ...somebody posted a link to it. Harbor Freight carries it too.

 

**** ******!

two words "reverse flush" . i flush via the heater hose (get a kit). Its amazing what comes out. DId you use a OE t-stat? The pipes in the heater core are huge compared to the radiator, so heater cores dont clog as easily as they used too, if ever.

 

nipper

OE stat yes, SubieGal!!!,

i used to use those kits on my old '64 chevys, worked great,

WOW....remembered something from 1974!!!

thanx nipper....great plan.....you da man:headbang:

Get the funnel it works wonderfully.

 

got lots....wear em every day....

 

oops....thought you said flannel

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