Cause of failure

Al Smith

Mac Daddy
Mar 6, 2005
Northern Ohio
I finally got around to disecting the 038 Mag I got as a parts saw from Rocky.As he had said the saw was abused by some know nothing types while in it's short time in service.

What had most likely happened was the poor old saw was jerked around until it broke the left hand side mounts completely loose thus tearing the boot,causing a slight leak.Most likely they richened up the carb or ran with the choke closed to keep it going. After the boot was finally about half torn into it just couldn't suck in enough fuel and died on the vine.

The actual failure was not a lean sieze but rather a super amount of carbon build up,from a rich mixture. The cylider,piston top and muffler were just full of oily soot,pyrolized oil in other words.

As a normal rule a case leak or seal failure will leave tramp aluminum all up and down the cylinder and fall to the crankcase.In addition often times the crankcase will have black residue as a result of a lower engine leak.

This example,the crankcase was clean,the bearings tight as it was a new saw.What small amount of scuffing can be lived with as far as a rebuild.

If I were using this saw to make a living with I would install a new cylinder and piston.Due to the fact that I'm going to soup this one up ,I can salvage the old parts. I have put together much worse that have ran good for years afterwards.
Good deal Al, glad it wasn't smoked. Are you going to turn her into a race saw, or just tweek it up a little? THe part number for the boot is #1119 141 2200 runs around $30.00 bucks.
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Just a highly tweeked woods saw.Being 71 cc's it falls too small to run in the under 80 cc class although if I do it correctly it should scoot.

I don't know if the picture tells much of a tale other than a lot of carbon.


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    038 Mag 002.jpg
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Hard to make out anything in the pic, suprised there wasn't more damage caused by dirt ingestion from the ripped intake manifold. Let us know how the rebuild goes.