Stuck valve??

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Bill Venohr
Posts: 90
Joined: Tue Apr 23, 2002 1:42 pm

Stuck valve??

Post by Bill Venohr »

Coming back from Oshkosh my engine developed a slight vibration and a noticable loss of power (lost around 100 rpm/7-8 knots). On inspection there was oil on the exhaust pipe of #2 cylinder. The cylinder was noticably colder than the others. First cut by my mechanic could be a cracked cylinder(best explanation for the oil). The mechanic fired up the engine with the same symptoms I had. He cleaned the engine thoroughly to see if he could find the leak, and fired it up and it ran smoothly with no oil visible. He pulled the exhaust to get a look inside.
His best guess is I had a stuck valve, which became unstuck. Compression was good, but he suspects the oil ring is the source of the oil when the exhaust valve was sticking. He commented there was too much oil in the bottom of the cylinder--very noticable around the plug area, although the plug was still firing. He also noticed a little corrosion on the cylinder walls as well as the valve guides being worn. So we are going to top the cylinder and hone out the rust spots (hopefully it will hone out or we are into more work on the cylinder). :x
After reading Joe's experience with a stuck valve it didn't dawn on me that might be what was happening to me--everything seemed too benign. I would have expected much worse vibration and power loss. Anyone else have this happen? I'll keep you posted on the results.
Bill Venohr
N4044V
Aurora, CO
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