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awd-drifter
05-09-2010, 05:14 PM
Just wondering if anyone can do this for me..or if I even need one. A guy over at Illinois is pretty serious about my car and he just wants me to do a leak down test. I'm not sure if I even need one because I'm guessing I may already have a bad valve seal.

Here's the issue; my car burns about a quart of oil every 1,000 to 1,200 miles. It's been doing this since I bought the car. Every time I start the car, there is a quick blue puff of smoke than it disappears after a couple seconds. My guess was the turbo seals going on me, but on start up with the e316g, it was still puffing blue smoke at start up. I last checked the compression after I got the e316g in and it was 150 across. Spark plug on cylinder 1 had a 'hint' of oil, a very very very small speck of oil on the spark plug. I was thinking it might have been the piston rings but I realized that there is some oil residue on the exhaust manifold gasket. Not much, but enough to make me believe that my valve seals are possibly bad. Can a leak down test prove where or why I could be leaking/burning oil?

Pushit2.0
05-09-2010, 11:31 PM
It sounds like you have a valve seal leak, no big deal. A leak down test will not show if your valve seals are leaking. The valve seat and valve seal are 2 different things. The valve seat is what holds in cylinder pressure and the valve seal holds the oil in the head.

What brand compression gauge and how did you perform the compression test? The numbers sound good, so no alarm there.

A leak down test will show where your cylinder pressure is going. A few common areas are around the rings, past the valve seats intake or exhaust, head gasket, or a hole in the piston.

~John

awd-drifter
05-09-2010, 11:36 PM
It sounds like you have a valve seal leak, no big deal. A leak down test will not show if your valve seals are leaking. The valve seat and valve seal are 2 different things. The valve seat is what holds in cylinder pressure and the valve seal holds the oil in the head.

What brand compression gauge and how did you perform the compression test? The numbers sound good, so no alarm there.

A leak down test will show where your cylinder pressure is going. A few common areas are around the rings, past the valve seats intake or exhaust, head gasket, or a hole in the piston.

~John

Brand of the compression gauge is Mac. We did my car, 150 across. We did my brothers accord and it was 250 across and did my cousin's talon with 170 across, he has 2g pistons/1g rod combo i believe. I'm wondering if I should just tell the guy I didn't do a leak down test and the compression numbers are still 150 across. Thanks though John. :)

awd-drifter
05-10-2010, 04:08 PM
Got another question...should I do a leak down test to see if if I am losing cylinder pressure? I know the the valves are leaking because of the symptoms and I know that the leak test won't show any leaky valves, should I do this test because I could be "losing" oil from the valve instead of the oil burning? if that makes any sense.