Hi All,

I just spoke with another Legacy owner, who recommended that I speak
with the folks at Niagara Air Parts (http://niagaraairparts.com/).

They will rebuild starter adapters and put the adapter back to the
pre-improved design (which is good).  They also recommended that I use
the old Delco/Presta Light/Teledyne Energizer (one of the many names
used for the same motor?) starter motor until such time as the other
lighter weight starters are beefed up.  This is what Kent (below)
recommended as well.

The story is that TCM tried to improve the starter adapter by knurling a
shaft and shortening the spring (if I recall my conversation correctly).
This was supposed to increase the friction of the spring and make the
system more reliable.  However, this had a net effect of shortening the
life of the starter adapter.  Normally the worse thing that happens is
that the adapter fails to turn the engine over.

The adapter coming apart in flight and dumping metal into your engine is
usually caused by starter motors that will not turn in reverse.  The
Iskra is notorious for this because it is so hard to turn statically.
Apparently, the old TCM manual used to specify that the torque needed to
turn an un-energized starter motor had to be 5 inch-pounds (or was it
inch-ounces, I don't remember) or less.  This basically means that you
should be able to turn the output shaft of a brand-new starter motor
with your fingers.

Alas, this isn't the case with the Iskra's and other geared, lower
weight starter motors.  They don't allow the spring in the adapter to
unwind, and this causes a lot of the starter adapter failures.

So, I guess I'm going to be flying around with a 12 pound starter motor,
but hopefully it will prevent starter adapter woes....we'll see.  I may
have missed or gotten some of these details wrong, please feel free to
correct errors mentioned above.

Kevin



----Original Message-----
From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of
Kent
Sent: Saturday, November 29, 2008 5:51 PM
To: lml@lancaironline.net
Subject: [LML] Re: Subject:,Starter adapter drive

hello

The TCM starter adaptors are stressed by the permanent magnet motors,
like
the Iskra brand and others.
The permanent magnet motors have high starting torque and more
importantly
do not relax after being de-enegized.   The start adaptor needs to be
able
to unwind a bit to totally disengage.

Aircraft Specialties Services found it was being blamed for warranty
problems that they knew was not their fault.  So they made a cutaway
starter
adaptor and made video of the mechanism on a running engine.

regards

Kent Felkins
Tulsa




----- Original Message -----
From: "Douglas Brunner" <douglasbrunner@earthlink.net>
To: <lml@lancaironline.net>
Sent: Friday, November 28, 2008 2:25 PM
Subject: [LML] Re: Subject:,Starter adapter drive


>I also had to replace the starter drive adapter on my IO-550 (non
turbo)
> after about 50 hours.  In my installation we only had to loosen the
bolts
> holding the engine, not pull the engine.
>