Good point, but most modern chainsaw engines utilize ball bearings now. His Poulan 33cc has ball bearings.

JWright36 - I will try to get a pic of those mounts posted later today. I strongly advise against doing any welding on the engine at all. The aluminum welding and brazing done with a torch are difficult to do no matter what anyone tells you, and often the welds don't hold up anyway. Besides that, there is the distinct possibility that you will warp an engine component while trying to weld on it. Sorry, but the whole idea is a "recipe for disaster". I will also show you a pic of how the sensor normally mounts when converting an engine such as this to CDI.

As far as compression, the only real way to test it is with the recoil starter hooked up and using a standard compression gauge. 150 psi would be a great engine, 90 psi would be well worn, and 70 psi will barely start, if at all. When doing this, if the engine hasn't been run for a while, give it a shot of WD-40 to help the ring seal as it would with a coating of oil in it when running. Don't use thicker, regular motor or two stroke oil as that will give you a "false high" compression reading, and be sure to block the throttle open while taking the reading if the carb is still mounted.

In lieu of that, you can check the ring gap. Ideally it should be very tight; about .003". Frank Bowman's excellent rings are actually fitted with zero gap.

AV8TOR