Hello Everyone!

 

I am new to this forum, i have been lurking for a good 2 weeks now.

 

here's my situation, a family member gave me a 1990 subaru legacy with a blown headgasket. it has the symptoms that everyone seems to talk about, overheating with coolant loss.

the past owner had problems with it over heating on the highway, or when driven hard. she took it to the local dealership to have it tested out. after doing a compression test they told her it was the headgasket.

 

So now that its time for me to do the work i decided to redo the compression test (at this time the car has been sitting for about 3 months). I warmed it up and went a head with the test. I tested each cylinder twice just to make sure. the results were rather good!

 

Cylinder 1 - 180 PSI

Cylinder 2 - 180 PSI

Cylinder 3 - 180 PSI

Cylinder 4 - 180 PSI

 

what the heck is going on here? to me this does not indicate a blown headgasket. could it be that its blown between a cooland and oil passage? I dont know what the liklyhood of this is because both oil and coolant are'nt under that much pressure?

 

can anyone shed some light on my problem??

 

BTW: when warming the car up i noticed that the check engine light came on. it threw code# 22, knock sensor. I thought id mention that just in case it meant anything.

 

thanks in advance!

The compression looks really good. Mine is around 165-170PSI average but I need to re-test it again.

 

Mmm I would flash the cooling system out and put in anti freeze in and drive the car and see if it does or doesn't over heat? Is there any signs of chocolate colour under the oil filler cup? (its a sign of water in oil) or funny colour in oil (you'll need to drain the oil) which shows water in oil?

If neither above then your head gasket is fine, but if you had cooling problem, i would go and check the radiator's core to see if its blocked or not - that is next thing i would see to trouble shoot cooling problems. Also how old is the thermosdat?

 

Cheers

AP

thanks for the suggestions, I'll have to take a look at that today!

the rad was replaced last year, and it was bled properly. I'll check the oil for signs of water. I didnt notice any oil in the coolant

Any foam or milky look in the oil? It could be an external coolant leak, simply leaking out somewhere. Did they find evidence of seepage, maybe some white, crusty buildup along the headgasket? It could be a coolant leak anywhere, even a leaking radiator cap.

Try having the coolant tested for exhaust gases - like carbon monoxide.

 

The head gasket leak is probably tiny and won't show up in a compression test. This has stumped many mechanics on these engines.

I'll have to ask around and see where i can get it tested....

 

well i got the car insured so I was able to take it for a test drive. I drove around for a good hour and a half. afterwards I had to top up the coolant with about a litre. I'm going to do an oil change tommorrow.