On
25 July at EAA/OSH, I spoke with Plane-Power Support Rep, Allen
Buffkin, who stated that Hartzell/Plane-Power have in development a
one-piece machined mount to replace the welded bracketry that has been
failing on many Beechcraft Bonanza engines. This new mount will only fit the TCM bracket PN: 628004. Hopefully, this will finally
put an end to failing mounting brackets on Beech airplanes.
Allen
also stated that they have alternator and generator replacement kits
that now fit the original factory generator mounts, which presumably
have survived the test of time on many airplanes. Click HERE for a link to their STC Approvals page.
Allen
has agreed to provide his mobile number for anyone needing more info on
this or other Plane-Power questions: (334) Three-Hundred
Six-Eight-Five-Nine.
OK, all you folks with Bonanzas with
generator
set ups and puny 50 amp alternators, check this out if you are looking
for more
juice to run your fancy new panel stuff or to stop brownouts during
night ops with your incandescent taxi/landing lights running.
Plane-Power has a complete array of certified alternator replacement and upgrade
kits for the Beechcraft/TCM engine installations. Check out Aircraft
Spruce for pricing!
Generator to Alternator STC Model Eligibility HERE
Here is an install pirep from Stan S. the Bonanza man
with an IO-470N:
We finished installing a new belt driven 70 amp Plane Power alternator on the
IO-470 in the Deb today. It comes with a new mounting bracket, new stabilizing
arm and belt tightening bracket. Everything fit perfectly. The Plane Power 70
amp alternator weighs 10 pounds, the same as the 50 amp InterAv alternator it
replaced, but it has a state of the art small voltage regulator that replaced
the InterAv's voltage regulator, over voltage relay and huge capacitor. The
Plane Power kit also comes with an "ALT INOP" 100 milliamp warning
light that must be mounted on the panel in the sight of the pilot and connected
to a power source through a one amp fuse or breaker on one side, and to a
terminal on the voltage regulator on the other.
We fired up the engine to test it and put about a 45 amp load on it, and at
950 RPM it held 14.1 volts. The staff at Plane Power told me this alternator
will deliver 70 amps at cruise RPM. Note not all 12 volt Plane Power alternators
are 70 amps, the gear driven alternator that fits on the E series engines is 50
amps, and they also have some 60 amp models. If you have a belt driven
alternator or still have the belt driven generator, this is a good option to
upgrade to current technology, and I like the warning light that will illuminate
if the alternator goes off line. Another Beech Boy recently installed the gear
driven Plane Power alternator on the E series engine in his E35, replacing his
old 35 amp generator, and is very happy with it, also.
Picture of the installation attached, when the picture was taken we were not
finished tie wrapping the wires, etc. The Plane Power alternator is physically
smaller than the InterAv alternator it replaced, but weighs as much, 10 pounds,
versus 17 pounds for the old 50 amp generator we removed about 7 years ago. We
replaced the InterAv alternator because it failed, bad bearings probably
resulted in physical damage to two of the three field/armature components or the
brushes/commutator, it would only produce about 15 amps and upon removal the
bearings were obviously worn out, the shaft had about 1/4 inch of end play.
We also replaced the drive pulley on the engine, the old one was a little
dented. That job was a little tricky, using a puller to get the old one off and
driving the new one on far enough to get enough threads on the shaft to move it
the rest of the way on with the nut. Not much clearance back there, but far more
clearance than Cessnas have!
Stan
35-A33 KSAC
Here is Stan's
Plane Power Install
GBelow is more of what Stan has to say on 2/28/2024 about his success with the PP bracket:
"I
will explain what I have done to successfully avoid a PlanePower
alternator bracket failure (these bracket failures in this thread are
referring to the belt driven alternator installations) and then I will
explain why I have done it this way.
I
adjust the belt tension looser than spec. Since the pulley on the
PlanePower alternator is relatively large in diameter, the belt does not
slip when adjusted fairly loosely.
I
started doing this after replacing an InterAv alternator with the
PlanePower alternator after the bearings failed on the InterAv
alternator. I caused that bearings failure because I had to keep the
belt tension very tight or the belt would come off. Then one day when
trying to figure out why the belt kept coming off, Larry Gaines was
visiting my hangar and noticed the pulley on the engine was warped! Got a
new pulley and corrected that belt coming off problem but shortly
after, the bearings failed on the InterAv alternator, and I upgraded to
the superior PlanePower setup and kept the belt tension relatively loose
so as not to wear out the bearings prematurely.😊Did
this before I learned that the mounting bracket PlanePower supplied was
marginal. With the looser belt tension, that bracket has lasted over
1,340 hours so far. 260 horsepower IO-470-N engine, similar to 260
horsepower engines in Barons with but with different intake setup."
Stan
35-A33 KSAC
The IO470 engine is known to
dish out quite a bit of vibration.
IO470 owners continue to
experience bracket failures through bracket Revisions, J, K and L.
HERE is a thread on Beech Talk going back to 2014 regarding Plane Power
IO470 bracket failures.
The above picture is from David F. and here is his pirep on his experience:
"........in our case the mis-alignment at the green arrow was so severe
(3 mounts so far) that it stretches the weld apart (the red arrows)
causing the cracks. We re-welded our bracket and relieved the holes to
achieve correct alignment of the bolts, correct alignment of the belt,
and so far everything is working.
Our last bracket cracked within 10 flight hours before correcting the mis-alignment."
Below is a Plane Power bracket that lasted 85hrs before failure on Daniel K.'s K35 Bonanza.
N35 Owner Pedro G. says:
"I’m
on bracket #9: changed engine mounts, balanced prop, shortened
alternator belt, made sure bracket went in place without forcing it, and
still no joy. Bracket #8 lasted 58 hours."
Below is a late model Baron
Alternator bracket with very beefy gusseting. Perhaps Plane Power engineers
might evaluate that design for a potential solution to their IO470 bracket
failures????
Here is an install pirep from
Baron B55 owner Joe B.
Put a pair of PP alternators on our
Baron this year (2009) and love them. Very clean output and the pair was
perfectly balanced out of the factory.
Below are pictures of Chris S.'s modified alternator bracket and comments on his Plane Power experiences.See the flex of his PP bracket in this movie HERE
Per Chris S.:
"Back in the days where Plane Power was Plane Power we ordered an alternator kit and they sent us the “gold mount”.It
required some Herculean efforts to install and we asked why they
couldn’t simply install the new alternator on the existing mount.So they made some changes and got it approved for us.
The
first rev had a design flaw and one of the alternator main pivot bolts
departed the airplane somewhere between Tucumcari and San Luis Obispo.The alternator hung by the tensioning arm and kept charging with belt intact.
We went to a single bolt through the alternator and spacers instead of two eliminating the hinge moment.
That worked well until the OEM bracket broke.We reinforced and welded it along with a shorter belt.Broke again and that’s when an intermediate arm was machined and welded in place.Been going for a while now.
Our experience with the Plane Power alternators has been great otherwise.The regulators and units work really well.
Last year end we purchased the Kelly Aerospace air conditioning system for the B55.It
requires a specific 100 amp alternator requirement that put out a lot
of current at low RPM because ground operations are where the system is
mostly used. The system is certified for all phases of ground and
flight. Very likely we will be upgrading our alternators.
Use
of a shorter belt changes the vibration characteristics of the
alternator by moving the alternator mass closer to the engine. "
Plane-Power 70 Amp Alternator Install Pirep
