Boy I ran into an unique problem with a Husqvarna 141 chainsaw. I was repairing it for fuel related problem IE carburetor. Once I got it running it ran fine for about 10 minutes during the tune up then all sudden a big puff of smoke and it died. Everytime I pull the cord it puff out smoke.
Well while checking for the root cause I notice the plastic cover was extra hot so I pull it and was going to do a compression test as it felt low on compression. Low and behold I found the problem as soon as I went to remove the spark plug. It was loose as a goose but not in the normal way. The plug assembly itself was so loose that the only way it could fire was against the metal shell as there was nearly .200+ clearance between the tip and the normal tip contact. Otherwords the plug ceramic piece was loose in the metal shell. I have never seen this before. Champion RCJ8Y