MS241C/261C chain brake request

[Shibby]

I'm wondering if anyone with a 241/261 can verify on theirs the tab (or lack of) in the picture. I'd like to know if this one broke off. I have a theory that if this tab is missing/rubbed away, or wasn't there from the factory that it might be the cause of the crankshaft wear when the brake is applied, but want to know if it should be there before I attempt a fix.

 

[Wood Doctor]

I doubt that you have a problem. I see no tab on the IPL. Run the saw.

 

[Homelite750]

The worm gear doesn’t look good. Time to replace it. I don’t think the tab, or lack of is the issue here.

 

[Shibby]

Good to know it wasn't there from the factory, I was originally afraid it had worn down somehow. The worm gear is planned to be replaced, it's just there to stop crud from getting behind it for now.

The 241/261's have the common problem of the crankshaft wearing down, eventually to the point the clutch hub will twist and put a bind on the clutch with the chain brake applied, ultimately killing the engine every time the chain brake is engaged.

My theory is, if there was a tab or if a tab can be added, it will prevent the chain brake band from pushing out in that spot which is what is causing the drum to twist and bind. This would prevent the need for a new crankshaft (which would eventually have the same problem), and stop it from wearing further when the brake is engaged. I've done a rudiment test that suggests this is the case.