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September 2nd 05, 01:47 PM
Hey all... My Cherokee is almost done with the annual, but in the 75 hours
since it was last inspected, the alternator bracket has cracked. It's complicated by
the fact that the plane was originally a PA28-140, but now has a Lycoming O-360-A3A.
So, the parts book doesn't necessary literally apply. From the picture, it looks like
it's P/N 65199-00. My mechanic says I should get the assembly, and that it has been
superceeded by a better part. Is that the P/N 63520-00 or the P/N 63698-00?

Also, where's an appropriate place to get a replacement? Piper only, or do
other folks sell them? If the bracket has been superceeded by another due to chronic
cracking, a salvage yard isn't necessary a good place to get one.

Thanks!
-Cory


--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

Jay Masino
September 2nd 05, 03:05 PM
wrote:
> Also, where's an appropriate place to get a replacement? Piper only, or do
> other folks sell them? If the bracket has been superceeded by another due to chronic
> cracking, a salvage yard isn't necessary a good place to get one.

You might try Airparts of Lockhaven. If they don't have it, they may
know where to get it. Also, I'm not sure if I'd be too worried about
getting a salvage one. If the replacement isn't cracked, it isn't
cracked. I still have an "old style" bracket, and it's still OK. One
thing you may want to make sure you have is the small bracket that sort
of "straps" the front of the alternator to the front of the starter. This
helps support the alternator. This extra strap was missing on my plane,
so we added it. The main bracket was supporting the alternator without
the extra bracket for an unknown number of years and it still didn't
crack.

--- Jay



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Jay and Teresa Masino ___(_)___
http://www2.ari.net/jmasino ! ! !
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Jim Burns
September 2nd 05, 03:51 PM
I'll second APofLH and add http://www.westexairparts.com/, email Mark, he's
very knowledgeable.
Jim

Bob Noel
September 2nd 05, 03:59 PM
In article >,
wrote:

do you need the one for an airconditioned 140?
(lots of those around - I could probably dig mine up).

--
Bob Noel
no one likes an educated mule

September 2nd 05, 04:38 PM
: do you need the one for an airconditioned 140?
: (lots of those around - I could probably dig mine up).

No, this one doesn't have A/C. After spending the whole morning calling up a
bunch of places, I'm pretty sure the correct part is 65199-00, which has been
superceeded by 65199-005. Most places don't have any in stock (big surprise). It
doesn't seem like it matters whether it's an O-320 or O-360, though. One piper place
I called suggested getting ahold of Lycoming. The two brackets they spec for an
O-360-A3A (07A21443 and 07A19474) seem to be for Ford and Prestolite alternators,
resp.... probably won't work for the Chrysler that Piper used.

A/C in a -140? Ughh... no wonder there aren't many left. They're doggy
enough without an additional 20 lbs and hp loss.

-Cory

--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

Jim Burns
September 2nd 05, 04:46 PM
Cory,
Try Mark at Westex, tell him I refered you. He also sells piper parts
manuals & CD's so he should know the correct part number. He's also got a
lot of NOS Piper parts so he may have one in stock.
Jim Burns

Mike Spera
September 2nd 05, 08:09 PM
20lbs. for air conditioning? Try 67lbs.

Mike

> A/C in a -140? Ughh... no wonder there aren't many left. They're doggy
> enough without an additional 20 lbs and hp loss.
>
>

nrp
September 2nd 05, 08:53 PM
The vibration environment at the lower front of 4 cyl Lycomings seems
to be quite brutal. On top of that the alternator mount on our 172M
was "scientifically" measured to be resonant at 80 Hz (hand blow with a
hand held accelerometer & a scope). Eighty Hz is also the torsional
firing frequency (@2400 RPM) and there is also a second harmonic (of
course that is also 80 Hz at 2400 RPM) yaw rocking couple in the engine
due to its mechanical configuration

Maybe that,s why so many of alternator brackets become cracked. Does
the newest Piper bracket address this resonance problem?

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