Number 5 Cylinder Problems

I did the Leak Down Test and Compression Check and the results indicated a problem with #5 cylinder. The compression ck. indicated that cylinder had the lowest pressure on that bank, about 12% lower than the others on that side. Not really a problem. The leak down test was a different story. Over 30% lower than all the other cylinders with indication of air escaping from the left collector, but sound could have been from oil pan.

Outlaw came over and we took both heads off. At this point, I had a one-track mind that the problem was the exhaust valve on #5 cylinder. After removing the head, we do not see any indication of a problem with the valve. Number 5 does have some small marks around the rim of the cylinder head next to the spark plug entry point and on the block at that same point, but it is very light marks.

I am going to have the heads checked an a valve job done. That has not been done for over 6 years (springs were changed 27 months ago, less than 50 runs).

After checking the heads, I will decide on looking at the rings, and changing them out for a set of normal tension rings.

April 17, 2021