Clutch inspection

[Philbert]

I checked the drum with a micrometer and it still seems to be round.

Again, it could still be round, but ‘stretched’. If the new chain does not do it, a new drum/ sprocket would be the thing to try.

Philbert

 

[HarleyT]

Show us the teeth of the sprocket first.

 

[Philbert]

Show us the teeth of the sprocket first.

You show me yours and I’ll show you mine!

The reason I mention the clutch cup/drum/spur sprocket thing ‘stretching’ was because it was a not-uncommon issue we used to have with our STIHL MS250s.

The sprocket teeth still had lots of life in them, and you did not notice distortion (several thousandths?), but it was enough to cause slippage

Philbert

 

[HarleyT]

Sometimes a person is fooled by a shot sprocket because the notches kind of look made that way, too.

 

[hosocat]

Here's a picture of the sprocket. I didn't want to disassemble the hub again. Hope you can see from this picture. I've seen sprockets with a groove cut in them from the chain drivers. This hub doesn't have any sign of that.

I went ahead and put a new chain on it. 12 inch chain with four broken teeth. Time to get rid of it?

On a side, does anyone have any good ideas of what to do with old chain? I hate throwing things away!

 

[Philbert]

does anyone have any good ideas of what to do with old chain? I hate throwing things away!

Probably best to just recycle it. If the new chain is the exact same make and model, you can save it for parts. Do you have the tools to splice chain? Otherwise, just throw it into a box with a bunch of other chainsaw related stuff, like the rest of us. People will find it curious at our estate sales.

Philbert

 

[HarleyT]

Here's a picture of the sprocket. I didn't want to disassemble the hub again. Hope you can see from this picture. I've seen sprockets with a groove cut in them from the chain drivers. This hub doesn't have any sign of that.

I went ahead and put a new chain on it. 12 inch chain with four broken teeth. Time to get rid of it?

On a side, does anyone have any good ideas of what to do with old chain? I hate throwing things away!

25:1!!!!

Maybe you should try synthetic!

 

[hosocat]

Yeah, I used 25:1 for a year or so, and I've gradually decreased oil to where it's about 40:1. I'll try and get some pics of the cylinder and piston to see if it really needed 25:1, or if that resulted in a lot of carbon buildup.

 

[HarleyT]

Yeah, I used 25:1 for a year or so, and I've gradually decreased oil to where it's about 40:1. I'll try and get some pics of the cylinder and piston to see if it really needed 25:1, or if that resulted in a lot of carbon buildup.

I was just joking a bit.

I like to start oil threads then leave.

 

[skeet88]

I was just joking a bit.

I like to start oil threads then leave.

You ain’t right ! Lol

 

[JD Guy]

Curious minds want to know:
Did the new chain cure your chainsaws ills?

 

[thenne1713]

Thanks for the observations, guys. Yeah, skeet. I had not noticed that broken tooth. Looked closer and saw that 4 teeth were broken off. That might explain why it was getting hung up in the cuts. That's the original chain, and some of the teeth were getting really tiny. I checked the drum with a micrometer and it still seems to be round. Guess I'll slap a new chain on it and see if that clears up the problem.

If you had not noticed broken cutters, I also suspect you are not sharpening often enough, too?