Plane Power alternators

[Mooney in Oz]

The purpose of starting this thread is to alert MSers whose Mooneys are powered by a Lycoming engine and with a Plane Power alternator. There is no criticism toward mechanics or Plane Power as it is a good, solid product with mostly no issues, however as with any aircraft component, wear and tear issues may arise after many hours in service.

I recently had a discussion with fellow MSer @PeytonM about my (probably) 20 year old PP alternator with about 800 hours of operation. During my last annual inspection my mechanic discovered large cracks in the rear aluminium alloy housing attached to the back of the alternator that had the potential to cause problems. The rear housing is difficult to see unless you actually look behind the alternator. He sent the alternator off to have the entire unit overhauled, plus the rear housing replaced. 

Peyton who also owns a J with a PP alternator about 400 hours old, mentioned he had the main wire leading from the alternator break in flight, causing the alternator to fail.

Despite the PP alternator is an 'on condition' part, my mechanic sends this type of alternator off to be overhauled at around 500 hours of time in service. I think this is a great idea.

In between, I think it is a good idea to conduct your own periodic alternator inspections by simply looking with a torch and feeling wires in case of a pending failure, particularly if you conduct a lot of night flying. 

[Fly Boomer]

9 hours ago, Mooney in Oz said:

Peyton who also owns a J with a PP alternator about 400 hours old, mentioned he had the main wire leading from the alternator break in flight, causing the alternator to fail.

This seems to be common regardless of which Mooney or which alternator.

EDIT:  We Americans are easily confused by words like "torch".

[Mooney in Oz]

29 minutes ago, Fly Boomer said:

We Americans are easily confused by words like "torch".

Flashlight (I had to Google the American version) 

[Pinecone]

Americans use torches also.  But not normally around aircraft due to the flames.

[EricJ]

2 minutes ago, Pinecone said:

Americans use torches also.  But not normally around aircraft due to the flames.

Great for fuel tank inspection.

[GeeBee]

Once you understand how fast an alternator spins, a 500 hour inspection is always a good idea. On the Continentals, I generally like to pull it off and replace the coupler.