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 Post subject: Engine smoke
PostPosted: Mon Sep 03, 2007 8:21 pm 
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Well it's time for another subject. I am tired of being a trouble maker and am asking for help. My engine started smoking bad this weekend. I did a compression test and had 150 psi on all four cylinders. Someone said it may be valve stem seals. Any other thoughts? And no I did not drill the valves. :roll:

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PostPosted: Tue Sep 04, 2007 10:44 am 
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A few things you need to check. First of all, there are no valve stem seals on the VW so forget that idea.
Check to make sure the valve guides are tight in the heads. I have seen them come loose and move around. This will cause excessive smoking.
Usually the primary cause is lack of oil control in the rings. Check the oil ring for excessive wear. You can still have good compression and have a worn out oil ring.
It might be a good idea to do a spark plug reading to see which cylinder is causing the problem. If you have a leakdown tester or can use your compression tester hose to inject that cylinder with air, that might help you find the problem without tearing it down first.

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PostPosted: Tue Sep 04, 2007 7:21 pm 
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I think Firebug is running a Subaru. Oddly enough the answer Roy provided is still correct except the part about having valve stem seals. And seeing that we are dealing with a overhead cam I don't think it would be from the top end. Not to say it's not possible, just not likley. When your running any high milage motors that were "lightly used" in their past life, the rings create a ridge in the top and bottom of the cylinder bore. When we start twisting on them like we do its posible that a oil ring could have broke. There could be to much oil in it, running up into the bottom of the cylinder bore. The oil is cooler than the bottom of the piston so it's possible to break a ring or crack a piston. Or it could be just worn out, time to call the bone yard and get another bullet.

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PostPosted: Tue Sep 04, 2007 8:34 pm 
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I think I will try the stem seals first, No big expense, just so I will know. I am still searching for another donor car. thanks for the info. 8)

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