Author Topic: camshaft/timing celeron gear  (Read 2587 times)

Woody

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camshaft/timing celeron gear
« on: March 23, 2012, 07:05:09 PM »
Anyone know anything about the replacement of the cam gear in the AC199E3 from the celeron gear to a metal one?  I read that this was a weak link in this engine.

Bill Poynter

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Re: camshaft/timing celeron gear
« Reply #1 on: March 23, 2012, 09:09:44 PM »
Since this is the gear that drives the mags, you should be able to remove one of them and see what you have. 

Paul Rule

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Re: camshaft/timing celeron gear
« Reply #2 on: May 08, 2012, 04:30:12 AM »
The bad gear was all celeron (or phenolic) including the teeth... which was what didn't last.  The 'new' gear has an aluminum rim & teeth on a 'celeron' hub.   Franklin Service Bulletin # 17  Feb. 13, 1942  addressed this and said replace them at overhaul (500hrs.)

The rate of wear (failure?) apparently was higher then they thought and with S.B. #21 of Dec. 7, 1942 (1 yr. after Pearl Harbor) they said pull any accessory and replace immediately if not previously done. 

If you have a 4AC-199 S/N 200533 or higher they came with the new gear.  If you have a 4AC-176 S/N 125270 or higher - same thing.

Old gear P/N not given - new gear  P/N 10725   (cost at that time was $6.00 !! )