Problem with engine starters

[nveneno]

In my company’s PA-28 Piper aircrafts, we are experiencing serious problems with the engine starters, for the Lycoming O-540 engines.

The problem is after a few hours (about 50 hrs.) wear on the Bendix gear becomes unacceptable. The same problem has happened on three different aircraft at least 5 times on the last year. It seams the Bendix gear do not retracts properly after the engine run.

We are using the starter P/N MZ-4222 from “Kelly Aerospace Power Systems” Inc. (Prestolite).

The Service Instruction Lycoming Nº 1154, establish as an alternative the engine starter P/N 149 NL produced by Sky-Tec. This starter is defined as a light weight – high torque, using an electric solenoid instead the mechanical Bendix. Sky-Tec uses as brand slogan “no Bendix – no headache”. The price is quite similar and that’s why we are thinking to move to this kind of starters.

Does anyone have experienced the same kind of problem with the Bendix type starters?

Does anyone have references about the Sky-Tech starters?

Nicolas Valencia

 

[thruthefence]

Is it the pinion gears themselves that are wearing, or the bushing the bendix shaft rides in ?

Poor starting technique can cause the gears to wear, that is engaging & dis-engaging the starter, during engine starts.

silicon lube should be applied to the shaft & bushing anytime the nose of the starter is exposed.

regards, Steve

 

[nveneno]

Yes Steve, it is the pinion gears that are wearing.
We are using the silicon lube ase recomended in the manual, but the problem persist.
thanks Steve

Nicolás

 

[MikeHalloran]

If the same mechanic replaced all the starters, then it's time to ... review the starter shimming procedure and specifications with the mechanic.




Mike Halloran
Pembroke Pines, FL, USA

 

[berkshire]

nveneno (Aeronautic

Sky-Tec. starters are lighter and spin the engine faster
Why would you not want to switch to them?
B.E.

 

[nveneno]

Mike

Our manuals (PA-28) do not specify any shimming procedure in the starter instalation.

Does anothe aircraft have a shimming procedure aplicable to this one?

thanks

Nicolás Valencia

 

[MikeHalloran]

I don't know. A Google search on the engine model found references to shims for starters.

Many car engine starters require shims to get the starter pinion gear lash correct, and the shims are easy to lose or overlook. It appears that perhaps the subject engines do, too.

<WAG> An official manual from Lycoming might be more detailed about stuff like that.





Mike Halloran
Pembroke Pines, FL, USA