MS261 bugger clucth side crankshaft. What to I need to buy for parts/tools?

[Henry E]

MS261 bugger clucth side crankshaft. What to I need to buy for parts/tools?

HLSupply has the crank on sale.
But what do I need for additional parts and for tools?
For parts I probably need new oil seals and probably bearings. A good time for new rings, piston looks good.
This is likely to be my one and only time to split a chainsaw. So I am not keen on spending more on buying one use tools then taking it to the dealer.
For example do I need a tool to split the cases and another to join the cases and yet another to pull the old crankshaft out and another to pull the new crankshaft in?

 

[HarleyT]

I tried to put up the manual, it is too large.
What is wrong with your crank?

 

[Henry E]

Poor needle bearing maintenance allowed the clutch drum to to smash the bearing parts into the crankshaft and were it down substantially. There is an impressive amount of movement when rocking the clutch drum. New Koyo bearing and clutch drum didn't make enough difference. Applying the chain break cants the drum and snubs out the engine.

 

[Henry E]

P.S. it wasn't me. I bought this used and it runs awesome. Just can't use the chain break. Something I need to fix or decide to sell the saw for parts.

 

[HarleyT]

Applying the chain break cants the drum and snubs out the engine.

Are you saying that applying the chain brake kills the engine?

 

[HarleyT]

Can you put up a pic?

 

[Henry E]

Yep. Drum tips to one side creating enough friction that the excessive drag kills the engine.

The deep gouging of the crankshaft under the bearing is very evident if you clean off the grease and look.
Swapping bearing and drum don't fix the problem. So the only thing left is the trash heap or a new crankshaft.

I would like to fix it myself. Hence the request for info letting me know how much I will need to spend in tools to do the repair.

 

[HarleyT]

What tools?
Put up a pic of the crank anyway.

 

[HarleyT]

Sounds like you need to turn down your idle.
But without a pic......

 

[HarleyT]

I think he really wants a reason to take apart his saw....

 

[Henry E]

Nope, really don't want to open it up. I am going to part it out.
Ticket closed.

 

[HarleyT]

Nope, really don't want to open it up. I am going to part it out.
Ticket closed.

How much for the whole thing????

 

[HarleyT]

Let's make a deal!!!

 

[aesmith]

Are you saying that applying the chain brake kills the engine?

It's a well known problem this side of the Atlantic. It's not clear whether it was bad cranks, bad bearings or bad clutch drums but it seems to have affected the majority of MS261s from release until at least 2016. Or at least it seems to have affected virtually every 261 offered second hand. The reason it stalls when the brake is applied is because the brake tips the drum far enough for the shoes to bite. Nothing to do with idle speed.

 

[HarleyT]

It's a well known problem this side of the Atlantic. It's not clear whether it was bad cranks, bad bearings or bad clutch drums but it seems to have affected the majority of MS261s from release until at least 2016. Or at least it seems to have affected virtually every 261 offered second hand. The reason it stalls when the brake is applied is because the brake tips the drum far enough for the shoes to bite. Nothing to do with idle speed.

Why wouldn't one take off the clip and washer, and show the bearing in the video?

 

[aesmith]

Why wouldn't one take off the clip and washer, and show the bearing in the video?

There would be nothing to see. The fitted bearing in that saw looked perfectly OK, except possibly under a microscope. Same amount of play with a brand new bearing. Much less with a new clutch drum but the end of the crank was dull and pitted. Not that easy to show in a photo ..

 

[HarleyT]

Do you know if there was a recall or tech bulletin published?

 

[aesmith]

Do you know if there was a recall or tech bulletin published?

Not that I've heard. Pretty much a denial from Stihl that there was anything more than a trivial issue, for example their response to me was as follows, with the implication that if the crank's damaged you're on your own ...

Thank you for contacting STIHL with your enquiry.

I have liaised with our Technical Team and we did have an issue with some MS 261 models where the clutch drums were going out of round causing damage to the needle bearing, and in some cases the damaging the crankshaft.

A steel drum was introduced mid 2016 and is included in rim sprocket kit, part number 1141 007 1002 (.325 Pitch 7 Tooth). The fitment of this, together with a new needle bearing, part number 9512 933 2260 to a machine with a serviceable crankshaft will resolve the issue.

 

[DND 9000]

From a other forum:

Just to add some balance to this thread. I bought a 261 C-M in 2016 and noticed a bit of pitting on the clutch drum inner surface. Took it to a stihl dealer who was completely transparent about the issue! Explained that the problem stemmed from a batch of rim/spline type clutches which didn't have high enough surface hardness where the bearing fitted. Was given a spur sprocket and told if it was still wobbly then the crank would be replaced under warranty. As it happens this work perfectly in till I swapped the bar/chain for their 3/8 Picco kit and a new clutch which has also worked perfectly. Not sure if there was ever a recall but I never had any complaints about stihl's customer care or the machine!

If you take the response that I received from Stihl as gospel the "bad batch" ran from introduction until mid 2016. It wasn't clear whether the part number they quote is specific to the "fixed" clutch. What the actually said was "A steel drum was introduced mid 2016 and is included in rim sprocket kit, part number 1141 007 1002 (.325 Pitch 7 Tooth). The fitment of this, together with a new needle bearing, part number 9512 933 2260 to a machine with a serviceable crankshaft will resolve the issue." Steel drum? Were the original drums not steel?

the complete discussion can be found here:
https://arbtalk.co.uk/forums/topic/113052-ms261-clutchcrank/

 

[HarleyT]

So the problem was the clutch, bearing, or sprocket?

Also, this idling with the brake engaged? Possibly the real problem, a poorly adjusted chainsaw?

Anyone here know of this problem in the U.S.?