MS 261 PTO side question

[Wonkydonkey]

What we (us consumers) need is some sort of poll, a is it, junk or good and yr serial etc. Not stihls bs..
A bit like apples bs that they could not get out of because of independent testing and reporting of there updates and other stuffs

 

[smokey7]

@richevy how the 261 run compared to the mofo 026s? How are they different? 261 is mtronic right?

 

[RI Chevy]

Yes. 261cm. I think when the bar is buried in a big log, the 261 seems to have a bit more torque and hold the RPM better. The 026 is a bit lighter ans still runs real strong. Tough to tell at this point. I am still looking for a real good piece if wood so I can run same bar and chain on each saw and do up a video.
261 is a real nice saw though!

 

[huskihl]

@fordf150 I believe was familiar with 261's having soft clutch side cranks

 

[fordf150]

old and new version both have soft cranks....thats my conclusion anyway since almost everyone i see needs a crank or is well on its way to needing one. bearings are always fine, they just wear into the crank.

 

[MattG]

Thanks guys, looks like I'll need to get Ben's saw PTO side serviced and greased probably a couple times a year (even after the bearing swap) just to keep it safe for him - or sell the saw.

 

[MattG]

261 is mtronic right?

Hi Smokey,

My mate's one certainly is MTRONIC, has a different master control switch style than the old skool stuff. I've not run it yet. But he speaks very well of the saw, I think he really likes the power-to-weight ratio of it.

 

[ferris]

Yikes. Ok. TY sir.

@nohoff
@ferris

Any of you guys have any info on these?

No, sorry

 

[MattG]

Back to theories about the issue, bad crank hardening treatment or underspecced bearing? I checked the specs for the 036 as a comparision, presumably a saw with a tad more poke than a 261....but not a great deal more.


see the * (NLA) entries, well these bearings have the same dimension as the 261s (indeed part 20* 9512 933 2260 is the exact same p/n). Well we all know that un-upgraded 036s suffered plenty of PTO side issues - drum wobble, causing oil gear arm and friends to erode the oil pump case. The fix by Stihl seemed to be a dimensional increase (bearing OD and drum center) from 13 -> 16.

Presumably Stihl should have learnt this lesson better and applied to same rationale in the design of the 261??

?

 

[RI Chevy]

Good point Matt.

 

[Wonkydonkey]

You could be on to somthing here Matt, good work

Cheers

 

[RI Chevy]

Back to theories about the issue, bad crank hardening treatment or underspecced bearing? I checked the specs for the 036 as a comparision, presumably a saw with a tad more poke than a 261....but not a great deal more.

View attachment 122375
see the * (NLA) entries, well these bearings have the same dimension as the 261s (indeed part 20* 9512 933 2260 is the exact same p/n). Well we all know that un-upgraded 036s suffered plenty of PTO side issues - drum wobble, causing oil gear arm and friends to erode the oil pump case. The fix by Stihl seemed to be a dimensional increase (bearing OD and drum center) from 13 -> 16.

Presumably Stihl should have learnt this lesson better and applied to same rationale in the design of the 261??

?

I did a little snooping today. Looks like the crank is the same size, just went a little bigger on the bearing which resulted in a different clutch drum as well. One with a bigger hole to match the slightly bigger bearing. That was the only difference I could see. The 036/360 still shows 1 crank.

 

[smokey7]

When you guys are assembling the clutch and the bearing are you "packing" the bearing with a very tackey grease like a open end marine type grease? Or just what ever grease you have around? Im betting it the bearing was greased with a heavier grease like the open end marine grease you may have a longer service life out of the bearing crank and drum. Ive heard of guys dribbling bar oil on the bearing during chain swaps but thats hardly a lube that would stay with the bearing for very long. So after my rambling on proper lube what are guys doing? Reason why i ask is ive seen really pitted bearings and shafts run a silly long time when proper grease is used. Ive got one running now on a old poulan the crank is wore with atleast a .025 step and pitted and the new bearing is 2 years old and atleast 30-40 cords of wood with no further wear or damage to the crank or bearing.

 

[RI Chevy]

I use red & tacky. By Lucas I think. Good for high heat.

 

[RI Chevy]

Amen on the micro spline!

 

[nohoff]

We sold around 200 MS 261s and had only 1 with a failed pto side crank.
Most of those cranks had trouble with the big end bearing.

Crank diameter on the outside is the same on a MS 261 and a MS 461

 

[MattG]

Crank diameter on the outside is the same on a MS 261 and a MS 461

The point I was making was the increment in the diameter of the needles in the needle cage assembly (and the larger cage itself). I don't have an IPL of a 461 to hand, but I do for the 460, and that most certainly has a bigger (i.e. stronger) needle cage assembly than a 261 - i.e. more similar in dimensions to that of the upgraded 036.

 

[Wonkydonkey]

Here’s the 461's , Needle cage 10x16x12
9512 933 2380.

Now doesn’t that look familiar

 

[Wonkydonkey]

Oh, and I think my 036 has a the smaller bearing, and it does wobble
The Stihl shop said it was just about serviceable,
I will get measurements juts for good measure

 

[RI Chevy]

My 036 has the smaller bearing too. I will check that one tomorrow too.