Well my Franken Poulan 505 I tore back down because it was not running right. I decided while I had it apart to install a Stihl MS660 piston. I bought one of the meteor pistons and installed with a stock base gasket. The old OEM piston was worn pretty good and I noticed a lot of slop around the skirt. Saw now has a little better squish and is now taching 14,200 and still 4 stroking good. I am not sure who figured out that conversion but all in all it was pretty simple to do.
This time I pressure checked and vacuum checked the crank case. Passed with flying colors. It turns out the issue with it not running right was the carb. The last thing I expected. So now it has a Jonsered fuel tank the Poulan 505 crankcase and a MS660 piston. Really is a Franken saw now, but it is a runner.
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