How did this run?

[atpchas]

A buddy brought me this 026. The view through the muffler showed no obvious scoring and the rings were free, but the saw had essentially zero compression. The carcass had no starter but I could spin the flywheel - the ONLY resistance occurred when the magnets passed the coil. I pulled the jug and found the piston and rings shown below. My question is how did the saw run enough to wear the rings so badly when it had effectively no compression. BTW, the ring gap is approximately 140 thousandths, maybe more.

 

[lone wolf]

A buddy brought me this 026. The view through the muffler showed no obvious scoring and the rings were free, but the saw had essentially zero compression. The carcass had no starter but I could spin the flywheel - the ONLY resistance occurred when the magnets passed the coil. I pulled the jug and found the piston and rings shown below. My question is how did the saw run enough to wear the rings so badly when it had effectively no compression. BTW, the ring gap is approximately 140 thousandths, maybe more.

View attachment 817908

View attachment 817909View attachment 817908View attachment 817909

Same way the Kohler 25 Command that I just rebuilt for a buddy ran with 100 thou end gap pretty weakly!

 

[RED-85-Z51]

Wanna bet he was using a drill to start it?

Sent from my LM-G820 using Tapatalk

 

[pioneerguy600]

32:1

 

[KASH]

I got a Sthil 350 cut off saw there was like an eighth inch piston clearance.That poor construction laborer must have spent a lot of the companies money trying to start it.
Kash

 

[Bob Hedgecutter]

Get your verniers out- are you sure it is not a late MS 260 top end on there (44.7mm) with 026 rings (44mm) ?

 

[rd35]

Thats what I'm thinking as well. How loose is the piston in the cylinder? The gap I am seeing would definitely indicate (to me anyway) that the rings are 44mm. I would also think that with no compression and the fact that the cylinder is in great shape should indicate that it never did run after the latest re-assembly/build.