New member need advice on MS360 Pro P&C damage

[bigblue12v]

Hey guys I'm Eric from Seymour Indiana just joined been a lurker for a while. Have ran Stihl handheld power equipment since I was a teen doing landscaping etc. Have plenty experience doing repair and fab work. Yada-yada... ok introduction over I was running my 360 pro Saturday cutting firewood, ran about 6 tanks of fuel through it. It was running out of fuel, I was trying to hurry and finish my last cut rather than stop and refuel for 10 seconds of cutting. On mine at least if I put it nose down, the pickup tube seems to get more fuel. So I was doing that, then needed to level it out and as I leveled it she was starving for fuel and died as I let it down to idle, so I set it down. Refueled and pulled the rope and she locked up after a few pulls. I was basically done cutting for the day so I loaded all the wood up and saws up and headed home. Just got a chance to tear into it a bit ago, see pics... I expected damage on exhaust side not intake. I'm not real familiar with 2 stroke stuff I mean I understand how it works and all but I'm not real good at diagnosing this kind of thing. My guess is she ran lean as it got too low on fuel. Carb was dialed in good she was 4 stroking at wot no load then cleaned up once in the cut. Running 32:1 mix in 93 octane gas. This saw is my baby and I need to fix it pretty much asap.
Parts from Bailey's I know but what brand? Anyone selling a ported cylinder right out of the box? This thing is tough but I wouldn't mind a little more umph.
Also I broke a fin on the flywheel using it to bar it over to unstick it (knew it was a bad idea) so need a flywheel too. Are these keyed shaft? And what is ignition module air gap to flywheel spec?

I hate when I get impatient... cost me a lot this time....
Thanks in advance for all the help I know I'm gonna get.
Eric

 

[jughead500]

You can probably sand that cylinder out and stick a new meteor piston in it.mastermind done a video on cleaning the transfer out of the cylinders.
http://www.arboristsite.com/community/threads/how-to-remove-aluminum-transfer-without-acid.248325/
First your gonna have to find out what caused the meltdown.
And check out some of our board parts suppliers
Chainsawcc.com
Chainsawsalvage.com

 

[jughead500]

Actually after looking at bigger pictures i dont think thats gonna buff out.

 

[Mad Professor]

Looks like metal dancing around inside. Bearing parts or ingested?

 

[bigblue12v]

I honestly don't feel real comfortable sanding it down it just doesn't seem very precise for something like this. It seems more like a gouge than a smear. But I didn't look at it too much really I was sickened enough I had to walk away. Like shooting your best horse because he's too far gone to save. Maybe if I get a new jug I can save this one to get redone and ported for later.
Yea I'm needing advice figuring out what caused it. This is where not being real familiar with 2 stroke diagnosis comes into play. Think me running it out of fuel while in the cut did it?
Thank you!

 

[old-cat]

Think me running it out of fuel while in the cut did it?

YEP

 

[bigblue12v]

Mad professor bottom end feels pretty smooth. Didn't think to shine a light down there but rings are fully intact.

Old-cat thanks hopefully that's all, worst to happen is put it back together and overlook something else.

 

[jughead500]

Has it been recently rebuilt?that piston looks good to be used very long.

 

[old-cat]

I'd take the carb apart to make sure everything in there is right.

 

[Mad Professor]

I'd take the carb apart to make sure everything in there is right.

Hmmmm, carb parts taste good!?

 

[bigblue12v]

Jughead the guy I got it from never had it rebuilt.
Old-cat, is there any particular reason I should take a good starting and running carb apart? How will I know if something's not right? It started and ran better than my other two stihls and there's nothing wrong with them at all other than one being a EPA gutless turd victim.

 

[Landmark]

YEP

Not disagreeing with you OC but how can running it out of fuel in the cut cause this type of damage? Ive ran out of fuel alot and never had this happen.

 

[lly_duramax]

From what I have seen the piston does not usually have scoring on the side above the wrist pin due to lean seizing. Are you sure it didn't ingest something? Are both wrist pin clips in the piston? I think someone may have had the jug off that saw. I have never seen a green base gasket and the aftermarket piston clips have a bad rep for coming undone.

 

[ft. churchill]

It sure looks like something went thru the saw. Check the piston pin retaing rings and see if they are still complete and or there at all. Sometimes the little ears or plier tabs will break off. Looks like lly dura and I are on the same track.

 

[Landmark]

Is there a retaining clip on the side shown in pic. I cant tell for sure but there is heavy damage right above it like it came out and worked its way up and over.

 

[old-cat]

Not disagreeing with you OC but how can running it out of fuel in the cut cause this type of damage? Ive ran out of fuel alot and never had this happen.

I screwed up! I should have looked at the photos! My assumptions are totally out the window.
I think someone has been into the saw and did a lousy job.

 

[ft. churchill]

Looks like dura posted up seconds before me. Seems we are both on the same track. Another thing that could "let go" inside of the engine is the ball bearing spacer cages. Very rare and you would probably heard bearing noises and or have a loose crank shaft.

 

[bigblue12v]

Here's some better pics, you guys nailed it! In the shop again now and was fixing to post pics when I saw lly-dirtymax post that about the clips. I took one out to get wrist pin out after I took first pics then I went inside the house. Totally missed that the other side was missing it's clip. You guys rock! Super glad to know it wasn't my fault after all! I'm so relieved now! The clip I took out was on the clutch side, missing clip is on flywheel side which is where it's damaged along with on intake side. The one thing I did wrong, which probably wouldn't have mattered either way, I had ear buds in jamming out while cutting. That was the first time I've done that while sawing. I realized after this that maybe if I wasn't doing that I'd have heard a clue. Too late now.

 

[bigblue12v]

Cylinder is scored pretty deep. Maybe it could be put on the shelf and later bored out to use with a bigger piston? Or just a souvenir?

 

[old-cat]

Cylinder is scored pretty deep. Maybe it could be put on the shelf and later bored out to use with a bigger piston? Or just a souvenir?

Nope it's trash.