Chain sticks when turned by hand...?

[Toby in Buckinghamshire]

Be sure its not the type that fit from inside the oil tank and locate in square first ......

Hi Stubby. How can I check that? And what do you mean by 'locate in square first' ?

[eldon]

Toby,

Hard to say from that angle, take a picture from the right hand side of this picture looking from the bar back into the sprocket viewing down the edge of the bolts shoulders.

 

If they are wind in studs from the outside, I'm not sure if they are or not on this model but they are on 241's, then the studs have both a left hand thread for location and a right hand thread for bolt clamping if memory serves me right. The coarse thread holding the stud on was only wound into the plastic, a real rubbish design.

Edited April 25, 2017 by eldon

[Stubby]

Hi Stubby. How can I check that? And what do you mean by 'locate in square first' ?

 

The inside wall of the oil tank has a location square cast into it for each of the studs . The studs have a square head and are assembled from inside the tank and pushed through to the outside . If they are of this type then you will round out the square location . They may not be though .......More common on Husqvarna .

Edited April 25, 2017 by Stubby

[Toby in Buckinghamshire]

The inside wall of the oil tank has a location square cast into it for each of the studs . The studs have a square head and are assembled from inside the tank and pushed through to the outside . If they are of this type then you will round out the square location . They may not be though .......More common on Husqvarna .

Thanks Stubby.

 

So I need empty the oil talk and look for the square bits then?

[bmp01]

Just been out to take the cover of my MS260. Got another idea for you what about the nylon chain rubbing strips pressing on the chain? Have a look at the attached pictures. The nylon strips are pressed into the cover, but they are pretty loose. So easy to remove and easy for wood chips get behind them and move then out against the chain. ... I think that would cause a little bit of drag on the chain.

 

bmp01

[Toby in Buckinghamshire]

Just been out to take the cover of my MS260. Got another idea for you [emoji38] what about the nylon chain rubbing strips pressing on the chain? Have a look at the attached pictures. The nylon strips are pressed into the cover, but they are pretty loose. So easy to remove and easy for wood chips get behind them and move then out against the chain. ... I think that would cause a little bit of drag on the chain.

 

bmp01

Good call (and thanks for taking the time to look at yours!) I did wonder if these might have been rubbing. I'll take them out and reassemble and see if it makes a difference! Thanks!

[bmp01]

Thanks Stubby.

 

So I need empty the oil talk and look for the square bits then?

 

Inside the tank I can just see the ends of the studs, as in round, end of a thread.

 

But actually i don't think the studs can put any sideways defection in the bar / cover. The shoulder on the stud would have to be unwound about 5 mm before it stops the cover going on. You can see in my pictures above there is a recess in the cover, for the stud shoulder to pass into if indeed it were far enough out to come through the bar. Your picture is showing the studs are either screwed right in or almost all the way in.

 

bmp01

[Toby in Buckinghamshire]

All, thanks for all your advice on this thread, much appreciated and I've learn allot.

 

Turns out that all that fuss was caused by a tiny piece of plastic coated garden wire caught under the 'washer' which sits over the clutch drum/spur sprocket. Photo below showing it! Only discovered it because I decided to take the clutch drum off to check that there was actually a functioning needle bearing in there!

 

The saw must have picked this up with it's past owner since it has only been used in pretty wild woodland by me! Chain is now running super silky smooth!

 

Thanks all!

 

Sent from my SM-G930F using Arbtalk mobile app

Edited April 25, 2017 by Toby in Buckinghamshire

[Stubby]

Brilliant ! . I like a happy ending !

[bmp01]

Result ! Thanks for the update.

 

Soooo, why did tightening the bar nuts cause the chain to not run smooth? Do you think it really was an alignment issue between the sprocket and the bar - because the sprocket had restricted sideways movement?

Or simply the wire getting into the rollers of the needle bearing under some conditions?

 

bmp01