ms261 needle bearing/play in drive sprocket, common problem??

[spudulike]

I have a 661 that eats plastic cage bearings and i check and grease regularly, has anyone got a part number for a steel cage bearing ??

 

Stihl use a fibre glass bearing, nothing wrong with that but 261s eat them and this kills the drum and usually the oil drive!

 

The metal bearings are usually aftermarket!

[Sambo]

Stihl use a fibre glass bearing, nothing wrong with that but 261s eat them and this kills the drum and usually the oil drive!

 

The metal bearings are usually aftermarket!

 

In what way does it damage the oil drive?

[spudulike]

In what way does it damage the oil drive?

 

The first thing to happen is the very end of the oil arm wears off, this usually makes the fit between the arm and the plastic worm drive very sloppy and in bad cases when the bearing becomes very worn, the drum edge wears through the oil pump.

 

I would have thought users would notice the lack of oil but have had a few in like this, just done one of the Mtronic ones - good on power and cut speed but the noise goes right through my head!

[Sambo]

The first thing to happen is the very end of the oil arm wears off, this usually makes the fit between the arm and the plastic worm drive very sloppy and in bad cases when the bearing becomes very worn, the drum edge wears through the oil pump.

 

I would have thought users would notice the lack of oil but have had a few in like this, just done one of the Mtronic ones - good on power and cut speed but the noise goes right through my head!

 

Took the clutch off and had a look at the oil pump. Seems like I've got away with any damage as I noticed the drum wobble early and put a new bearing in. A new clutch drum tightened things right up but it is a rim/spline type so I'll have to keep an eye out!

Edited December 24, 2016 by Sambo

[spudulike]

Took the clutch off and had a look at the oil pump. Seems like I've got away with any damage as I noticed the drum wobble early and put a new bearing in. A new clutch drum tightened things right up but it is a rim/spline type so I'll have to keep an eye out!

 

I trust you checked the oiler arm was located in the clutch drum slot OK?

[GardenKit]

I trust you checked the oiler arm was located in the clutch drum slot OK?

Haha, that would tighten the drum up nicely

[Al Cormack]

Had mine rebuilt under warranty even though it was 18 months old. It's a known problem with Stihl.

 

As to greasing the bearing, was told it wasn't necessary with all the chain oil flying round in that area.

 

 

http://www.cormacktreecare.co.uk

[Sambo]

I trust you checked the oiler arm was located in the clutch drum slot OK?

 

Yeah. There's a little line on the outside surface of the clutch drum to help get it on - handy for shortsighted people like me! In certain positions you can also just view it from the side. Interesting how, even with the clutch drum fitted correctly it seems to side high compared to the casing with the brake ribbon quite close to the bottom.

The roller bearing seems to be shorter than the inside surface of the clutch drum - seems a bit strange!

[spudulike]

Sounds fine to me, noticed the bearing shortness before, nothing to worry about!

[Pinkfoot]

Yeah. There's a little line on the outside surface of the clutch drum to help get it on - handy for shortsighted people like me! In certain positions you can also just view it from the side. Interesting how, even with the clutch drum fitted correctly it seems to side high compared to the casing with the brake ribbon quite close to the bottom.

The roller bearing seems to be shorter than the inside surface of the clutch drum - seems a bit strange!

 

I noticed that . Thought about putting two in ,but don't think there is enough room.