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N86250
02-13-2018, 11:10 AM
Bobby's Prestolite starter on an O-200-A went T.U. The drive locked up. We want to replace it with a Skytec. No Problem--no, wait---there is a needle bearing for the Prestolite drive in the starter adapter between the engine cases. So if I try to pull the bearing out of the adapter, I see it deforming and dropping bearings into the accessory case. Crap! If I leave it in there I see bearings falling out during operation. Crap! Am I going to have to pull the engine and the accessory case because of that bearing just to put a starter on it? Crap! Skytec says I can leave the bearing in there, no problem. Have any of you mechanic types done this and left that needle bearing in there?

bob turner
02-13-2018, 01:27 PM
Check with B&C before making any decisions. They have a special tool for pulling the bearing, and will chat with you about problem areas. Also they are independently owned. Skytec is part of the huge lightplane industrial complex.

I installed two B&C starters a year ago. They get daily use, and never a problem. We get between 40 and 70 starts per charge on a small Odyssey PC-545 battery.

Charlie Longley
02-13-2018, 10:15 PM
I haven’t done one of these starter changes in a while. But I remember taking a dremel tool with a cutoff wheel to the pinion. The needle bearing is on the starter. It seemed a little sketchy to me but worked out well. It’s spelled out in the STC.

hotrod180
02-14-2018, 12:09 PM
I believe the pull-start O200's need the shaft inside the accessory case cut off.
But as I recall the key-start O200's are different, that might be what the OP is posting about.

N86250
02-14-2018, 01:15 PM
Thanks guys. My problem was solved and I didn't know it. Like Charlie I was aware of the pinion shaft that had to be cut off to replace a Delco Remy pull type starter. Like Hotrod suggested we have a Prestolite key type starter that uses a bearing in the engine case instead of the pinion shaft. I was aware the first starters from B&C and Skytec were made to replace the pull starter. I was unaware Skytec had a model designed to make the very swap I needed. The C12ST2 starter has a machined nose to fit into the bearing I was worried over. The C12ST2-S doesn't have this nose. Not only will that nose keep the bearing secure, it will also limit the oil flow through that bearing so we won't have an internal oil leak with the resulting drop in oil pressure. I was about to be blindsided with that oil leak. By the time I had figured out all would be OK, Bobby had also found the answer and ordered himself a starter.
Bob, thank you for your glowing recommendation for B&C. I didn't talk with them this time, but I will be looking for a starter for my C85 later and I will call them first before I start my overhaul. jrh

cubdriver2
02-14-2018, 01:25 PM
Glad you found an answer but don't understand any internal leaking. I removed the whole 2lb pinion from my C85 12 years and over 1000 hrs ago. Hole on side fits on dowel index pin, hole on end might weep a few drops once in a while.



https://i.ebayimg.com/images/g/4ZcAAOSw-U1aUUNN/s-l1600.jpg
Glenn

bob turner
02-14-2018, 02:00 PM
B&C recommends against the Dremel idea. I used hacksaw blades and lots of modeling clay. The problem is, when you get halfway through that pinion, a small hole opens up, allowing abrasive dust to go into the main crankcase. With a hacksaw, you can clean up with a magnet.

It takes a very long time to saw that sucker off. My current engine - a Stroker with 20 hours on it - took two minutes on the lathe. Anybody who builds a C-85 or 90 should do this automatically.

N86250
02-14-2018, 03:04 PM
35232

This is the starter adapter that is in this O200. The Prestolite starter drive shaft fits in the bearing. One hole in the circumference is for the dowel. The other hole is oil to the bearing from a vein in the case. The needle bearings were my worry point. I just learned that oil vein would need to be blocked off if we didn't have something to replace the shaft in the bearing. The Sprague clutch locked up on our starter and the clutch is now is made of unobtanium. I am pleased it is being replaced anyway. That clutch would engage and turn the starter backwards when it was necessary to turn the prop backwards. Then it would drag a bit when turning the prop forward. Checking or setting mag timing was an exercise in worrying if this is OK or worse or not. This was the only Prestolite starter I've been around so there was nothing for me to compare with. jrh

hotrod180
02-15-2018, 01:51 PM
Everybody seems to prefer the later key-start on the O200, but I think the pull-starter is better from the owner's point of view.
The only time the Sprague clutch is working on those is when the starter is engaged.
The key start clutch is turning all the time. Unfortunately the TBO on those needle bearings is not as long as the engine TBO.
I had one come apart once, all the pieces tinkled down into the sump (and wherever). Major bummer.
I dunno how the B&C and Skytec starters engage with regards to a clutch, Bendix, or ??
Hopefully a better design than the original key start.