Sa200 gear tooth

[_gomez_]

So I removed the magneto since it has no spark and inside the timing cover I found, what appears to be, a broken tooth off the gear. Before I start tearing my sa200 apart, I just want to make sure it is totally necessary. I checked the governor and nothing seemed to be missing off the gear. Any help is appreciated.

[BYW200]

Doe's the Impulse coupling still snap, when you turn the mag over by hand?

[duaneb55]

That's not a governor, cam or crank gear tooth. They are all helical type.

BYW200 might be on to something with the thought of a piece from the impulse coupler. Specifically the end of one of the "dogs" that make contact with the stop screw to cause it to wind up before it releases. But even then, it looks too small for that.

Is it a metallic or fiber material?

[_gomez_]

It's metallic. And the impulse coupler does snap.

[guajilloweld03]

My first thought was a part of cam thrust washer/ hold on plate .

[duaneb55]

It's metallic. And the impulse coupler does snap.

Twice for every revolution or only once? What brand mag?

My first thought was a part of cam thrust washer/ hold on plate .

Too small for that I believe. Both 2-bolt and earlier 3-bolt designs.

I still think it's part of an impulse coupler dog.

[guajilloweld03]

Broken dog would go with no start or hard start condition.

[duaneb55]

Agreed on possible hard start as the impulse coupler wouldn't catch for every other cylinder with one bad dog but it wouldn't surprise me if it started with no problem with just one - if that's where this piece came from.

[_gomez_]

I believe it is. I fished out another piece and looked at the mag and sure enough he impulse coupler was broken.

[duaneb55]

Which make mag? Just curious.

[_gomez_]

Which make mag? Just curious.

It's an American bosch

[duaneb55]

That's why the piece didn't look like a Fairbanks-Morse impulse coupler dog.