Stihl MS261 stalling when chain brake applied

[key261]

Hi everyone

 

Apologies if this has been mentioned before, read up on past posts but I have a slightly different issue.

 

Basically, the saw dies when the brake is applied. The saw has had a new clutch, rim sprocket set including drum and needle bearing, brake band, and new oil worm gear. Now there is movement in the drum, video will show:

 

 

 

So when brake is applied, the drum is being forced into a weird angle and stalling the engine. Anyone have an idea of what to look at next? I've had a look at the crankshaft and its seems ok, a tiny bit of wear but I think its what you'd expect from a 2011 saw. The needle bearing has hardly any movement on it.

 

Thanks everyone!

[EricBradley]

Whats the new bearing like? looks like its gone, take it apart and have a look if you haven't already.

[peatff]

Is the drum located on the oil pump drive?

[key261]

Hi guys.

 

The drum is on the oil pump drive. And I've tried 2 new bearing, one being the plastic stihl genuine one, and the other being a metal aftermarket one. Both show the same result, excessive drum movement. I just had it all apart again and i'm starting to think the crankshaft has worn down to much.

[carlos]

the one at work has a knackered crank, just over a year old, sat under the bench as too expensive to fix, shame as a nice saw when working properly.

carl

[jmac]

Yeah it sounds like your crank is knackered. It will have worn through lack of grease or running a worn bearing for too long. Seen a couple 261 s with this problem.

[spudulike]

If that is a new Stihl drum and bearing, the crankshaft is worn. You can measure the diameter of the shaft where the bearing runs and then where it doesn't. Of the difference is over around 0.2mm, you have a real issue with the crank.

[Riggerbear]

I've been asked to sort a couple of these, new crankshaft unfortunately.

Once you price it using original parts, there's not much difference between the parts and a new saw

[Taupotreeman]

We had one do the same. Kept replacing needle bearings but the crank still wore. Came to an agreement with Stihl, they paid parts and we paid labour and it was rebuilt. Now it's doing the same thing again. Good saw and piece of junk in the same sentence.

 

 

Sent from my iPhone using Arbtalk

[twsread]

We bought six 261s and after a season of running well the crank has worn on four of them and we are seeing the same issue.  Really unimpressed as we'd been looking after them.  First signs were needle bearings going and before long it would stall and not start with the chain brake on.  Now considering buying new saws and not sure what to replace them with.  Any suggestions?