Stihl 025 - Chain Not Turning

[TomGraz]

I have a Stihl 025, and am very pleased with it.

This past weekend I had the chain to stop turning. I think I shut it down before any real damage occurred. The motor sounds fine and is running quite well. Forgive me if I don't know the correct names of the parts. I removed the chain and bar. The sprocket would turn with difficulty if I used pliers. I removed the sprocket noting carefully where the Jesus clip landed. Inside the "cup" of the sprocket was some pretty tough, sludgy residue that I thought might be the culprit. It cleaned up without much trouble. Then I couldn't get the sprocket back on. A few observations made me want to ask for some advice.

I haven't gone any farther yet. I see inside where the "clutch assembly" is, there is a metal band that forms a ring around the clutch. It doesn't want to come out. I think there might be a tab on the ring holding it in place. I see there is a "break" in the band. It appears to be at a slant. I can't tell as of yet if that "break" is supposed to be there to allow the band to compress or if it's broken. And I don't know if the band goes inside the sprocket cup or outside the cup. I tried both being careful not to force anything and couldn't get the sprocket back on. Do I need to remove the plastic "inner housing" to do that?

A few more questions:

Is the metal band supposed to have a break in it?

Am I barking up the wrong tree? If a tree barks in the forest and nobody hears it, should you cut it down? What if it was a spider on the tree? You have to watch out for barking tree spiders while your sawing logs. They'll get you in your sleep every time.

Should I be concentrating on the clutch assembly?

Are any special tools need to get the sprocket back on?

Thanks in advance,

Tom G.

 

[PES+]

The band is the chain brake band

You tripped the brake and you need to push the chain brake handle back forward until it clicks.

If you can post picks it will help us to see if you have damage.

 

[bcorradi]

Are you sure the brake isn't engaged?

 

[bcorradi]

Pes+ beat me to it, but you need to pull it back to disengage it.

 

[Scooterbum]

opcorn: opcorn: opcorn:

 

[PES+]

:monkey:

Yah.....what BC said....pull it back not push it forwards

 

[TomGraz]

I've never tripped the brake before so it didn't occur to me to check it.

I will tonight and report back. Any thoughts about getting the sprocket back on?

Thanks,

Tom G.

 

[bcorradi]

Once you disengage the brake you will have room to get it back on.

 

[PES+]

It will go right in with the brake disengaged

Provided there isn't another problem.

Are you familiar with chainsaws and how to work with them safely?

I am not ragging at all I am just wondering if you are new to using saws.

 

[PES+]

Pictures would help

I just read your other thread and suspect you may have damaged the clutch housing by not cleaning it out.

The goo you found might be melted plastic which may have caused brake band failure.

Do you have a camera?

 

[TomGraz]

The residue was more like super heated, oil infused, ultra fine sawdust that adhered to inside of the sprocket cup. No metal and no plastic. If I didn't have to work today, I'd run right home and try these fine suggestions. Thanks for the quick replies.

Tom G.

BTW, I've seen first hand what a saw will do to a leg (not my doing or my leg). I have respect for their potential and exercise great caution, but I'm not afraid of them. In many years of cutting, I've never tripped the brake. Good fortune or careful use? Who knows. I fix computers for a living, not small engines. I feel comfortable trying minor repairs, that's what led me here. Thanks for the concern though.

 

[PES+]

Well......as soon as I stop pushing on this pull cord maybe I can help you out

Ain't easy push starting chainsaws

Might help if I stopped listening to the Tubes Completion Backwards Principle while I am between cylinder swaps

 

[bcorradi]

Ok ... if you could get a picture of the area it would greatly help determine what damage was done, if any. It will also help us guide you through reassembling it.

 

[bcorradi]

If you didn't hold down the throttle or work the throttle repeatedly after the chain stopped turning....you probably didn't cause any damage.

 

[TomGraz]

It was the brake. I feel silly for not thinking to check something that should be so obvious. Everything went back together and the saw is working properly again. Maybe a bit better after cleaning the inside of the sprocket. Thanks for the help.

Tom G.

 

[bcorradi]

Well on the positive side you learned a little more about your saw and cleaned it off a bit .

 

[Sprig]

Well on the positive side you learned a little more about your saw and cleaned it off a bit .

+1 And learned to keep it that way mate!



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