Bought a used MS261 - what should I do with it?

[Rockjock]

Thanks Rock, I should calm down before I start pulling everything off. Guess I'm a bit excited to get my hands on it. Lol.

Nothing the matter with being excited. Just slow things down and do the basics. That is what I do when I get a saw with unknown history. Just check the basics and go from there. Many times a saw is not leaking it is just the oil that was on the chain or the bar rails that slowly seeps out. Taking off the bar and chain and a good cleaning will soon show you if it is a oil leek or just normal egress from the bar and chain. The fresh fuel, a sharp chain and have at it!

 

[Full Chisel]

Will do, thanks for the tip. Not sure if I will take off the limiters though, as I'm not that experienced and don't want to run the risk of leaning out the engine. But I'm sure like you guys here, the disease will take hold and I will be forced to start modding and buying more saws. Guess I should warn the wife.

You run a greater risk of leaning out the mixture by NOT taking the limiters off. Many of them don't allow the carb to be adjusted rich enough to run properly IME, especially in cold weather.

I would definitely address the clutch/drum, brake and oiler parts with the saw apparently being run with the brake on. Otherwise if it runs well I wouldn't worry about the low compression. If it gets low on power, a new ring would probably bring it up to spec, or a new piston if it has some light scoring.

 

[Rockjock]

You run a greater risk of leaning out the mixture by NOT taking the limiters off. Many of them don't allow the carb to be adjusted rich enough to run properly IME, especially in cold weather.

I would definitely address the clutch/drum, brake and oiler parts with the saw apparently being run with the brake on. Otherwise if it runs well I wouldn't worry about the low compression. If it gets low on power, a new ring would probably bring it up to spec, or a new piston if it has some light scoring.

I would have to disagree my friend. I see a great many 026/ms260 and pre Mtronic 261's with unmolested carbs running just fine with 0 issues. Broad statements like that do a disservice to fledgling saw owners IMO. Can they run better with some tuning? Yes they can, will they blow up stock? Not bloody likely.

 

[GoingOffGridNWO]

So, I have the best wife in the world, I had my saw on the coffee table watching the hockey game and she didn't even give me one hairy eyeball...she's the best (no she doesn't read this forum so I'm not trying to get brownie points).

Anyways, good news is that the piston looks pristine, no signs of scoring or anything and even the rings were nice and shiny and smooth so I'm confident that the engine is sound, so thinking the pawn shop owner didn't know how to do the compression test properly. I attached a pic of the piston, so any comments are welcome.

I'm also attaching some pics of the clutch and sprocket area, and now I think (experts please chime in) that this sprocket is beyond worn out and probably the reason why the chain is loosening/tightening on it's own. I removed the sprocket and the needle bearing. The bearing was pretty much bone dry, and I think is not quite right (again correct me if I'm wrong), it seems to have a lot of play in it (posted a pic of the bearing on the snout, then one with me pushing my finger on the side of it to show the slop in the bearing).

Didn't get to remove the clutch assembly yet (it was past my bedtime) to see if I could find any source of bar oil leakage, but will probably fire it up before I do that because obviously being shipped it has no fluids in it.

So experts, lets hear your opinions on things so far.

 

[bmwpowere36m3]

The sprocket is garbage.... put the drum on and feel for any play at the bearing end. Should be pretty tight. Drum, sprocket and bearing are fairly cheap ~$30-40

 

[GoingOffGridNWO]

The sprocket is garbage.... put the drum on and feel for any play at the bearing end. Should be pretty tight. Drum, sprocket and bearing are fairly cheap ~$30-40

That's what I kind of figured seeing what a new sprocket looks like...lol. Here is a pic of the inside of the drum bearing surface. I'm thinking I might replace it because it looks a bit worn.

 

[GoingOffGridNWO]

So the saw runs great, just have to tune it once I get the proper sprocket on it. Turns out the reason this sprocket is so chewed is that the dummy that had it before tried to run a .325 pitch chain on a 3/8 sprocket. That would explain the damage on the cover and why it was going loose and tight all the time, the chain was probably dancing around inside there like a madman. Anyways, I ordered a sprocket/drum/bearing for it so should have it this week. Also found a new (well out of a new saw) oil pump, oil tube and pickup body on ebay (genuine stihl) for $20 so couldn't pass that up, I think my oil leak is just an old oil tube that isn't making a good seal with the saw body.

So once I get that stuff, I'm going to tune it. I tried running and tuning the saw without a chain, and quickly realized that it probably isn't going to work because I need to tune with the drag from the chain on the bar taken into account, but the saw starts like a champ (first or second pull) and runs well. Just wanted to thank you guys for the help, I've learned a ton from this site already and I just joined.

 

[SeMoTony]

Thanks Rock, I should calm down before I start pulling everything off. Guess I'm a bit excited to get my hands on it. Lol.

new tools/toys get me started better than hot coffee in the morning little pe'od I missed a ported 066 by couple days out of a month earlier post ;-(

 

[GoingOffGridNWO]

new tools/toys get me started better than hot coffee in the morning little pe'od I missed a ported 066 by couple days out of a month earlier post ;-(

Every time I go into Canadian Tire, I seem to come out of there with some new tool that was on sale. I'm realizing that retirement is going to be dangerous for me because I will have all the time in the world to spend in that store amongst others.

 

[mowoodchopper]

Keep it.