MS260 modest compression quick fix?

[RedShift42]

Came home this evening to find the lower-48-er who bought nearby some nearby property has run amok dropping trees, as they always seem to do, to build his Alaskan fantasy "cabin."
Seems the guy has no plans for the wood (so much for any frontier cred) and they're mine for the taking-- if I can move pretty fast. Unfortunately my 026 is sidelined with bad crank seals, but I do have a nice recently-acquired 260 Pro, sold cheap b/c it bogs in the cut and has 145psi compression.
Apologies b/c this has been addressed a hundred times before in various forms, but I'm in a pinch and want to fix this tomorrow before someone else scoops my score...

Just pulled the cylinder, everything looks perfect to my inexperienced eye. No striations to be found anywhere on piston, rings, or cyl walls; Heck, the walls have a smooth, almost mirror-like finish.
What's the best and/or quickest way to freshen this saw and get it in the game?

There's a Stihl shop nearby so parts should be available and yes, the usual rubber bits will be replaced while I'm at it.

Thanks!

-Eric.

 

[jackjcc]

Probably just needs a tune up. If it loses power in the cut then the H circuit on the carb probably is a little lean.


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[Duane(Pa)]

Deglaze the cylinder and put a set of oem rings on your piston, carb kit plug, AF & get to work.

 

[blsnelling]

Put it back together, tune it, and go get your wood.

 

[RedShift42]

Deglaze the cylinder and put a set of oem rings on your piston, carb kit plug, AF & get to work.

AF... I presume you mean carb tune?

Put it back together, tune it, and go get your wood.

Do you mean reassemble as is, or are you reiterating above suggestions to replace rings and scuff the cylinder with a Scotch-Brite first?
With their altered displacement, did the 260s run lower compression than the 026s? My never-opened 026 still makes 170psi so I assumed that's what I should be shooting for.

Thanks for all the replies!

-Eric.

 

[blsnelling]

I wouldn't touch the cylinder wall if there's no damage. Check your ring gap. If not way excessive, I'd put it back together until after you get your wood.

 

[a. palmer jr.]

I've found out recently that seals on an 026 aren't hard to install if you have the right tools..Uhh, I need to modify this statement, "The clutch side is easy to change, I still haven't figured out a slick way to remove the flywheel side seal." My homemade puller found out that one was a little stubborn.

 

[RedShift42]

Just to update-- not b/c my results are particularly interesting but mostly b/c I dislike reading old threads where there's no resolution. It's poor etiquette for the OP to just disappear.

I discovered the air filter was pretty much pasted air tight, which would account for the seller's complaint of bogging in the cut. With that addressed I followed the advice here and reassembled the saw as-is, save for lightly scuffing the bore with a scotch-brite pad (don't know why, just seemed like I should do something while in there and those mirror walls were too darn shiny), and replacing impulse & fuel lines.
Buttoned back up, compression now improved to 145-160, a second 5/16" hole poked in the muffler, and it's running well, tho' a little more carb tuning is in order.

As for the trees, word is the land owner may have ticked off somebody, work stopped and nothing is moving. But I'm not too disappointed, it provided the pants-kick I needed to get this very nice 260 running.

 

[Duane(Pa)]

When I said AF, I meant Air Filter. I don't think most people service them as often as they should.

 

[cedarshark]

Just to update-- not b/c my results are particularly interesting but mostly b/c I dislike reading old threads where there's no resolution. It's poor etiquette for the OP to just disappear.

I discovered the air filter was pretty much pasted air tight, which would account for the seller's complaint of bogging in the cut. With that addressed I followed the advice here and reassembled the saw as-is, save for lightly scuffing the bore with a scotch-brite pad (don't know why, just seemed like I should do something while in there and those mirror walls were too darn shiny), and replacing impulse & fuel lines.
Buttoned back up, compression now improved to 145-160, a second 5/16" hole poked in the muffler, and it's running well, tho' a little more carb tuning is in order.

As for the trees, word is the land owner may have ticked off somebody, work stopped and nothing is moving. But I'm not too disappointed, it provided the pants-kick I needed to get this very nice 260 running.

Can you not cut as many trees as you want on your property ?

 

[RedShift42]

When I said AF, I meant Air Filter...

Oh, duh. -forehead slap-
Yeah, these 026/260 AFs need attention after every outing so I'm surprised I didn't catch it immediately. But then again, had it been noticed sooner the seller wouldn't have let the saw go so cheap.

Can you not cut as many trees as you want on your property ?

Of course, but I prefer my own trees in their vertical form. If a neighbor is offering his free & conveniently it'd be crazy not to.