Leaking Starter Pinion

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170C
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Leaking Starter Pinion

Post by 170C »

An age old question--how do I stop the starter pinion (best description I can come up with) from leaking? I know a light weight starter would solve that problem, but I was looking for a possible solution that didn't cost $500-$600. It seems that there is a seal (maybe Garlock) that goes in the housing. Just wondering if some of the others may have a specific description and part number plus any other tips on stopping the problem.
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LToxvard
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Re: Leaking Starter Pinion

Post by LToxvard »

I feel for you, as I have the same issue, but have yet to find a good solution. I have wiped grease around it and it slows for awhile. I have just learned to wipe the belly down after every flight, kind of like I do with Rudder my dog after a good walk.
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GAHorn
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Re: Leaking Starter Pinion

Post by GAHorn »

Steve Grimsley wrote an article about this some time ago in which he mentioned the several seals available, some of which worked better than others. Anecdotally, I've heard of a leather automotive seal (Chicago Rawhide mfr'r) which had good results. I'll try to find that source and post it.

According to the Niagara Installation Instructs: (bold added)
3.3 Inspect the bushing in the starter housing. Inspect the starter housing and determine if the housing is
machined for an oil seal. If the housing is machined for a seal, ensure that the correct seal is installed
(the seal should not protrude above the machined surface of the housing). If the housing is not machined
for a seal, a leather packing is required.

The "leather packing" is merely a flat washer that slips over the pinion shaft and acts as a "slinger" to prevent oil from passing thru the housing. I'm thinking that it might also be added in addition to any existing Garlock seal, as long as it does not prevent the full dis-engagement of the gears.
Here's a pic of the Garlac type seal...which should be installed facing the interior of the engine. (Obviously if installed backward (unlikely) it will contribute to a leak.)
oilsealstarter.jpg
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
jetwhine
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Re: Leaking Starter Pinion

Post by jetwhine »

Fresno Airparts has the rebuild kits for it.
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170C
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Re: Leaking Starter Pinion

Post by 170C »

Thanks! Mine has a seal, maybe it needs replacing. I have one. Is the brass item that the pinion rides on in the housing a bushing? Has oil(?) holes in it.
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David Sbur
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Re: Leaking Starter Pinion

Post by David Sbur »

The brass looking stuff is an Oilite bearing.

George has an article I wrote for the 120-140 Association he might post, PM me and I'll send along what I know....
WA State Rep. Intl Cessna 120-140 Asso.
Cessna 140 1946 N110V
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GAHorn
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Re: Leaking Starter Pinion

Post by GAHorn »

David Sbur wrote:The brass looking stuff is an Oilite bearing.

George has an article I wrote for the 120-140 Association he might post, PM me and I'll send along what I know....
These are also posted in the MX Library.
http://cessna170.org/forums/viewtopic.php?f=39&t=14320
THANK YOU DAVE!
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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