Hoytster
ArboristSite Member
So I bought a brand new 576xp off a guy on ebay. The saw was brand new with maybe a 1/4 tank run through it (USPS doesn't want to know how I know that), but didn't look like it cut a thing. Bar was flawless, chain was flawless, no saw chips or dust anywhere on the saw, cylinder looked brand new, ect ect. From the tag on the case, it looks like a 2013 model.
Anyways, I put in some good bar oil and some good 32:1 mix fuel (amsoil saber) for the initial break-in. I ran about 4 tanks through it, taking it somewhat easy in some big oak. I pulled the muffler off afterwards to look at the piston, everything looked great. Went out to cut a week later with the same 32:1 mix. I ran it harder this time cutting some bigger oak logs and oak stumps. Came home, pulled the muffler off and this is what I found.
Looks like lean scoring to me, but would like other peoples opinion. So, in response to this, I drove the ball bearings out of the carb limiters and removed the limiter caps so I can fully adjust the carb. I also did a dual port muffler mod to help her breath a little better (Ignore my first attempt at brazing, I usually weld these together) .
I also checked the saw for any leaks and couldn't find any. It also doesn't act like it had an air leak. After I re-tuned the saw, I ran it through some wood and checked the cylinder again, and didn't see anymore scoring on the cylinder. I noticed though that the high adjustment on the carb doesn't really seem to do much. I can pretty much turn it full closed or full open without much, if any change in the "sound" of the saw. It actually seems to run great where its at, but what might cause this? Or is this normal for this saw? I know I need to get a tachometer to really properly tune the high end.
Anyways, I put in some good bar oil and some good 32:1 mix fuel (amsoil saber) for the initial break-in. I ran about 4 tanks through it, taking it somewhat easy in some big oak. I pulled the muffler off afterwards to look at the piston, everything looked great. Went out to cut a week later with the same 32:1 mix. I ran it harder this time cutting some bigger oak logs and oak stumps. Came home, pulled the muffler off and this is what I found.
Looks like lean scoring to me, but would like other peoples opinion. So, in response to this, I drove the ball bearings out of the carb limiters and removed the limiter caps so I can fully adjust the carb. I also did a dual port muffler mod to help her breath a little better (Ignore my first attempt at brazing, I usually weld these together) .
I also checked the saw for any leaks and couldn't find any. It also doesn't act like it had an air leak. After I re-tuned the saw, I ran it through some wood and checked the cylinder again, and didn't see anymore scoring on the cylinder. I noticed though that the high adjustment on the carb doesn't really seem to do much. I can pretty much turn it full closed or full open without much, if any change in the "sound" of the saw. It actually seems to run great where its at, but what might cause this? Or is this normal for this saw? I know I need to get a tachometer to really properly tune the high end.
