Replacement engine for Stihl MS180

[heimannm]

It looks to me like that key has been sheared off, and the tapered bore of the flywheel looks as though the saw was running with the flywheel loose and the taper bore has had some damage done to it.

Do your best to thoroughly clean up that bore and make sure the stub of the key is aligned with the keyway on the crankshaft when you reassemble the saw. Also be sure to torque the flywheel nut properly. You should have been able to get the workshop manual from the links in earlier posts.

Mark

 

[Koper]

It looks to me like that key has been sheared off, and the tapered bore of the flywheel looks as though the saw was running with the flywheel loose and the taper bore has had some damage done to it.

Do your best to thoroughly clean up that bore and make sure the stub of the key is aligned with the keyway on the crankshaft when you reassemble the saw. Also be sure to torque the flywheel nut properly. You should have been able to get the workshop manual from the links in earlier posts.

Mark

I'll try to do that, I'm also considering and I would like your opinion about it - to cut a key way in the flywheel and to use a woodruff key, if I measured right, it should be 3x8mm, at least that what I measured on the shaft's key way. as per the workshop manual, unfortunately I didn't found it, even though I've got a message to check my inbox. I'm ashamed to admit that I couldn't find my inbox. if you or any other member is willing to Email it to me, I'll highly appreciate it.

 

[heimannm]

Certainly it is possible to cut a keyway in the flywheel and use a more conventional key in the crankshaft. I have not found it necessary so far to do that as I have been able to rely on the taper to fix the flywheel in position.

Mark

 

[farmer steve]

I'll try to do that, I'm also considering and I would like your opinion about it - to cut a key way in the flywheel and to use a woodruff key, if I measured right, it should be 3x8mm, at least that what I measured on the shaft's key way. as per the workshop manual, unfortunately I didn't found it, even though I've got a message to check my inbox. I'm ashamed to admit that I couldn't find my inbox. if you or any other member is willing to Email it to me, I'll highly appreciate it.

Your inbox looks like an envelope at the top of the page.

 

[sean donato]

I'll echo Mark. yes, you could cut the flywheel for a key, but there's no real reason to do so. It's just for ease of assembly, and it looks like you have enough left to get it lined up just fine.

 

[Koper]

I'll echo Mark. yes, you could cut the flywheel for a key, but there's no real reason to do so. It's just for ease of assembly, and it looks like you have enough left to get it lined up just fine.

I'll try to assemble it and and see if it's enough indeed.

 

[GMB74]

There actually is an advantage to this situation. You can intentionally misalign the the key stub in the flywheel with the keyway in the crankshaft resulting in a slight ignition timing advance. Most of these smaller saw engines benefit from such a modification by producing more power. Try about 1/4 keyway width to start. If you don't like the result, pop the flywheel back off, line up the key and keyway and you are back to factory spec.

 

[ZeroJunk]

Certainly it is possible to cut a keyway in the flywheel and use a more conventional key in the crankshaft. I have not found it necessary so far to do that as I have been able to rely on the taper to fix the flywheel in position.

Mark

Not unusual on those Stihl saws that have the threaded hub to screw the puller in and it sound like a 22 rim fire when it pops loose.