Help with an MS441?

[bigbarf48]

I found a guy on CL that is interested in trading his ms441 for my 170 + cash. I've only talked to him a little bit, but he says that "the chain gear messed up". After some questioning, I figured out slightly more specifically what he meant by that

He is under the impression that there's something wrong with the sprocket and the clutch. I asked what happened and he said "the chain came off".

I am awaiting pics now

My questions are: Can you guys figure out what might have happened any better than I can based on this guys vague descriptions? I looked around the web some, but cant seem to find replacement clutches for the 441, however I did find a replacement sprocket, anyone know where to get a clutch (I guess my dealer would probably be easiest)?

Id need to look the thing over before knowing anything definitively, but figured Id ask here to see what you guys think

 

[Jon1270]

Here's the clutch, although I doubt it would be affected by the chain coming off the sprocket. Here's the bearing, and if it failed then it could certainly make the clutch seem "messed up." For some reason the illustrated parts list doesn't show a part number for the clutch drum, but it's got to be a fairly standard item. I can't guess what's broken any better than you can, but it shouldn't be too big a deal unless he somehow broke the crankshaft.

 

[Woodfarmer1]

Or it's as simple as he has no clue what he's doing and the chain didn't have enough tension and popped off. Sounds like its too much saw for him anyway, get it and send it to me, thanks

 

[D8Chumley]

Nice, post up pics if you get it!

 

[bigbarf48]

Here's the clutch, although I doubt it would be affected by the chain coming off the sprocket. Here's the bearing, and if it failed then it could certainly make the clutch seem "messed up." For some reason the illustrated parts list doesn't show a part number for the clutch drum, but it's got to be a fairly standard item. I can't guess what's broken any better than you can, but it shouldn't be too big a deal unless he somehow broke the crankshaft.

Thanks for the link Jon

Or it's as simple as he has no clue what he's doing and the chain didn't have enough tension and popped off. Sounds like its too much saw for him anyway, get it and send it to me, thanks

This is kind of what it seems like to me just in my limited communication with the guy so far

 

[Clarkbug]

My guess is that the chain came off the and could have screwed up the sprocket if he still had it running at full tilt.

Unless the saw has seen a hard life otherwise, probably a pretty good deal! (just figure you might need a new bar and AV mounts if he has been ragging on it hard enough to throw the chain...)

 

[bigbarf48]

The guy says its 3 months old. If it goes through ill be sure to check it over really good. Hopefully ill get some pics of it today.

It kinda sounds like he got too much saw and now wants to downgrade. I imagine a 441 throwing a chain is a rattling experience , especially if you're new to saws

 

[Jon1270]

441 to a 170 is a heck of a downgrade.

 

[bigbarf48]

Oh I agree. It's all kinda weird but to each their own. We'll see if it even pans out and if I can go check it out. Hopefully it will but who knows

 

[Fifelaker]

I'm coming up with part# 1128 160 2900 and 11280160 2902 for the clutch drum. I believe Oregon makes one also.

 

[bigbarf48]

Here are the pics I received from him today:



He says everything spins freely. I asked if he knew exactly whats wrong or just that it threw the chain, he says he doesn't know. Anyone see anything horrendously wrong in the pics? I've never had the privilege of running a big saw like this, so I don't exactly know what it should look like in there

 

[salecker]

The guy says its 3 months old. If it goes through ill be sure to check it over really good. Hopefully ill get some pics of it today.

It kinda sounds like he got too much saw and now wants to downgrade. I imagine a 441 throwing a chain is a rattling experience , especially if you're new to saws

Looks like it was a rough 3 months

 

[Vizsla]

Did you price the clutch? I don't think that one is cheap. What did the guys say at arborist forum

 

[Jon1270]

Doesn't look bad to me. It's low-res and hard to see, but before taking the second pic it looks like he removed the retaining washer and clip that hold on the sprocket and clutch drum. The only thing that's obviously broken is the rim sprocket, and it is totally shattered. But, that's a very cheap part. There's a good chance the washer was also damaged, but that's an insignificant expense too.

The darkness of the dirt and the staining of the plastic under the sprocket-side cover is a little unusual. Makes me wonder whether he was using old motor oil for bar oil. That wouldn't be any sort of death knell for the saw, but maybe an indicator that he's less than fastidious with maintenance (which would be no surprise given the circumstance). You might want to ask what kind of 2-stroke oil he favors, and hope he doesn't say "used motor oil" for that too.

The recoil-side pic looks nice. The dirt and the wear on the handle tell you it hasn't spent it's time since manufacture sitting on a shelf, but I don't see anything too scary. If this is all that's wrong then whether it's a good deal just depends on how much cash he wants along with your 170.

 

[Jon1270]

Aftermarket sprocket

OEM kit including clutch drum, sprocket, washer and retaining clip

 

[bigbarf48]

Thanks for the help and links Jon! I thought the amount of oil and how dark it is was a little odd too. Ill ask him about his two stroke habits.hopefully the answer will be "stihl silver bottles" and not "what's two stroke oil"

So from what I can tell, assuming the saw needs a new clutch, sprocket, rim sprocket, and little bearings/washers; I'd be looking at around ~150 bucks in parts. But I can't be positive the clutch even needs replacing since we can't see it

Out of curiosity, what happens to a saw to shatter the rim sprocket like that?

 

[Jon1270]

Out of curiosity, what happens to a saw to shatter the rim sprocket like that?

I can only guess. I haven't seen it before, but I also haven't been working on saws for all that long.

I have an MS460, currently in pieces. The guy I got it from thought the crankshaft or rod had broken, but instead it turned out that the piston had shattered. He said he'd recently replaced the clutch, and now that it had broken again he was done messing with it. When I took it apart I found that the clutch shoes were discolored (blue) from overheating, and the worm gear that drives the oiler had failed, so my best guess is that the oiler stopped working but he didn't realize it, the chain got too tight, but the saw was powerful enough to keep it cutting anyhow, overheating the clutch and putting extra stress on the piston until it finally broke. Maybe something like that happened with this one too? It would be interesting to examine the bar that was on it when it failed.

 

[Jon1270]

So from what I can tell, assuming the saw needs a new clutch, sprocket, rim sprocket, and little bearings/washers; I'd be looking at around ~150 bucks in parts.

Maybe, but that's a worst-case scenario and kind of unlikely.

How much are you considering giving him along with the MS170? Maybe $150-$175 or so?

 

[bigbarf48]

I hope not, a new piston is getting out of my college-student price range . Ill have to check out the bar and the clutch carefully. I assume a shattered piston is something that can be seen from pulling the muffler? Thing sure looks like it was oiling though. A lot!

 

[Jon1270]

Oh, I didn't mean that the piston on yours was likely to be shattered, just that a lubrication problem might have put extra stress on the sprocket and caused it to break.

 

[Jon1270]

Thing sure looks like it was oiling though. A lot!

Could easily be that the oil holes in the bar were plugged with sawdust, so the oil wasn't getting where it was supposed to go. When the pump is still trying to push oil into the bar but the necessary holes are plugged, it's normal for it to leak out all over the place and make a mess of that whole area under the sprocket cover.

 

[bigbarf48]

Maybe, but that's a worst-case scenario and kind of unlikely.

How much are you considering giving him along with the MS170? Maybe $150-$175 or so?

Yep, this is what Im thinking my top dollar will be

Could easily be that the oil holes in the bar were plugged with sawdust, so the oil wasn't getting where it was supposed to go. When the pump is still trying to push oil into the bar but the necessary holes are plugged, it's normal for it to leak out all over the place and make a mess of that whole area under the sprocket cover.

Makes sense

So could rim sprocket failure cause a thrown chain? Im just wondering how that happened, since thats been his most helpful attempt at explanation thus far. It seems like poor lubrication would cause the chain to tighten, not loosen. So I wonder if it overheated, tightened in the bar, tore up the sprocket, and THEN it came off the bar


PS- Sorry for all the questions, but I sure appreciate the help!

 

[Jon1270]

So I wonder if it overheated, tightened in the bar, tore up the sprocket, and THEN it came off the bar

That's my best guess, but these pics aren't a whole lot to go on. If the price is right and it doesn't require a 3-hour drive then it would be well worth going for a look.

 

[Jon1270]

If you don't already have one, stop by a Stihl dealer and pick up one of those L-shaped T27 torx wrenches to bring with you. That's all you need to pull the muffler and get a look at the piston.

 

[Clarkbug]

Makes sense

So could rim sprocket failure cause a thrown chain? Im just wondering how that happened, since thats been his most helpful attempt at explanation thus far. It seems like poor lubrication would cause the chain to tighten, not loosen. So I wonder if it overheated, tightened in the bar, tore up the sprocket, and THEN it came off the bar


PS- Sorry for all the questions, but I sure appreciate the help!

My guess is that the thrown chain caused the rim sprocket to break.

Poor lubrication would lead to increased friction, which creates heat, which makes the chain stretch. If you are trying to force a saw to cut with a dull chain you can see when you pull it out of the cut that you have a lot more chain droop. If you dont know better, you can toss the chain off the bar pretty easily when its warm like that. (Cant really tell if the chain catcher is bent in the first pic, but if you see it and its mangled, you know what might have happened...) Toss that chain around to where it twists up and wants to stop spinning, you put a lot of stress on the rim sprocket, and a good chance it will break.

Looks like used motor oil to me, or just really dirty cutting. You may want to check and make sure it oils once you get your hands on it, could have a plugged oil pickup.

Probably dont need a clutch, maybe not even a clutch drum, but most definitely a rim sprocket. Since he has already pulled off the washer and e-clip on the outside of the clutch drum, pull it and see what it looks like under there. Thats a good chance to see if the crank is OK. If the end of the crank is at all damaged, you might want to back away slowly.

So parts list will probably be: rim sprocket, clutch bearing, chain catcher. May need others as you dig in, but its a good place to start. Swish some mix in your oil tank to clean it out, then fill with fresh bar oil and see if you can get oil from it.

I suppose the other thing, does it run? You should be able to start it without a bar/chain on it if you put that e-clip back on the end of the crank. Dont rev it up without the load, but hopefully it fires right up.