The International Cessna^® 170 Association

Hey all you smart folks: The object in question is the original Delco-Remy starter. I don't know what the geared thing is called that plunges into the accessory case, but its tip is coated with copper (?) and is pitted/damaged. Is this something to be concerned about? Can it be re-coated? Please excuse my lack of starter savvy....And thanks in advance for educational input. Shawn

The thingy is the gear and shaft that is located below and in front of the starter motor. the gear itself ends up inside the accessory housing and when moved into position, completes the drive train from the starter bendix gear to the gear on the end of the crank. You can see it in this picture.
The stuff on the end of the shaft, for the most part is not inside the accessory case. From memory the stuff is likely a copper/bronze bearing like coating. It's purpose mainly is to provide some bearing surface between the spinning shaft it is on and the fixed starter lever that is pushing on the end of it to move the gear into position and completing the starter drive train.

While I would have to study your shaft and the starter housing, I'd say from the picture the pitting you see should have no effect. It is on the side of the shaft, not the end where it needs to be to work. The critical thing is does this rough area ever enter the bearing that the shaft itself rides in located in the lower starter housing? I'd say from the picture there is no evidence of this, as you can see where the shaft rides in the bearing.

Could it be recoated? Probably. Could you find someone to recoat it and then be sure it is still a legal airworthy part? Probably not.

Thanks Bruce! I guess I had it backwards. The starter worked perfectly before the engine was disassembled, so I wouldn't thinkit has any bearing on the performance. If something does go wrong down the line, I'll look there first. Are these starters easily replaceable? Or only with newer modern variations?

I don't think they are difficult to replace with the same part. Replacing with a new smaller geared starter has some challenges the can be overcome such as grinding out the stud that the bendix rides which is held in place by the engines case halves. Also they would require some mods to the electrical system most notably a switch and relays to engage the starter since the beldon cable control would not be used.

If this were my starter, I'd note the pitting, ensure no interference with the bearing area then make sure the rest of the coating was not coming loose, and then I'd install and use it.

I would simply use a small platers wire brush ad some WD40 or like light oil and work the corrosion off the starter clutch and protect it with a little corrosion preventive.

the copper is a plating there to protect the shaft from corroding. it never enters the accessory case. When you have the starter off, it is easy removed from the starter buy pulling it forward, it will slide out.

Ok, thanks all! I shan't worry about it then...

As you've learned from others...it's unimportant.
Also, (strong personal opinion here), the original starters are widely available, relatively inexpensive, dependable, easy to rebuild, plentiful, and simple. Keep it.
And, while those who've spent money on them are reticent to admit it and cringe when it's pointed out...The new "lightweight" starters are....well.....lightweights. Overpriced, and (some models) are underengineered. Neither are more robust than the original Delco-Remy's.... and although I hate to not give full support to a Texas product, in my opinion, the B&C lightweight starters are much better than the Sky-Tecs. (sorry Frank)

I can't believe that any self respecting pilot would call that subject engine part a "Thingy" when any male aviator with over 300 PIC hours knows that a "Thingy" is the devilishly awkward little device that is used to fasten a brassiere strap in the back.

Well, blueldr,
I've always tried to be careful of corrosion on any "Thingy" I Get my hands on. I don't want any part of a Thingy with corrosion. :~0