Starter Pinion Pitting

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superpilotjustin
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Starter Pinion Pitting

Post by superpilotjustin »

Hey everyone,

I had an intermittent issue recently with my starter. It would work fine one minute and then do absolutely nothing the next. So we pulled the starter to take a look at it and consider our options of rebuilding or replacing with a SkyTec. As you can see in the picture we got the wonderful surprise (sarcasm) of finding some pretty major pitting on the crankshaft.

We plan to scope down and see if there is pitting anywhere else inside the case, but I wanted to go ahead and ask the group for advice. Has anyone seen a similar issue (it’s a C-85 engine)? Is it indicative of a larger problem? Or, do we cut that shaft off, put in the SkyTec, and not worry about it?

Thx,
Justin
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Last edited by superpilotjustin on Wed Dec 11, 2024 5:20 pm, edited 1 time in total.
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6643
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Re: Crankshaft Pitting

Post by 6643 »

Fortunately, that is not your crankshaft. Continental calls it the starter pinion pivot (pn 23487). That's the good news. Better news is, one of the two common starter replacements has you cut that shaft off. I don't remember for sure, but I think it is the B&C starter. Then again, it could be the Skytech. Worth investigating.

It also may have something to do with your starter issues.
superpilotjustin
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Re: Starter Pinion Pitting

Post by superpilotjustin »

Thanks, John. Wasn’t sure if that was the right word to begin with so I appreciate the explanation.

The SkyTec does call for cutting that shaft off. Just hoping there isn’t anymore pitting anywhere else….
tonycondon
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Re: Starter Pinion Pitting

Post by tonycondon »

the split line between the case halves above the pinion...looks odd. It looks more like a crack than a split line.
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Re: Starter Pinion Pitting

Post by 6597 »

Here's my cut off starter pinion, did it at overhaul so it was nice and clean. Skytec. 0-200. Suggest you cut it off as far as possible for the engagement throw. Skytec has a neat little plastic cup like thing so you can do the cutting and not get a bunch of crap in the case. A little modeling clay is useful. Measure depth according to the instructions to be sure. Note my case half above the pinion is tight.
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6643
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Re: Starter Pinion Pitting

Post by 6643 »

tonycondon wrote: Wed Dec 11, 2024 7:05 pm the split line between the case halves above the pinion...looks odd.
Yeah, I noticed that too. Figured it was too odd to be real.
superpilotjustin
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Re: Starter Pinion Pitting

Post by superpilotjustin »

Thanks everyone. Sounds like pitting on the pinion isn’t cause for alarm that there’s pitting other places. Definitely think a SkyTec is in my near future…
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