Plane Power Alternator

[Magnum]

I installed a 70A 24V Plane Power Alternator. Wow, what a difference. The Prestolite was only able to produce 24-25V with engine idling (850 RPM), strobes and avionics on. At the same RPM the voltage of the Plane Power stays above 27-27,5 V with Nav lights, strobes, pitot heat and avionics on. Both are rated 70A.

[carqwik]

I installed a PP Alternator to replace one of the Prestolite OE alternators in my M20M.   I second the original post. 

[Jeff_S]

Just took my first flight with the new Plane Power alternator and so far me-likey.  My old Prestolite style (which, upon further examination, wasn't even a correct model for my plane!) always put out enough power but at low RPMs it was developing a very nasty pinging, which also increased when any major load was put on it.  I turned on everything thing I could during today's test flight and the power output was very steady with the new alternator.  I hope continued testing proves this out.  Electrical systems can have so many gremlins that show up and are difficult to track down.

[KSMooniac]

It is a fine unit!  I replaced my Presto with the PP late last fall and am very happy.  

[John Pleisse]

I moved up to a PP 100a-14v STC. At idle, with nearly everything on at night, nothing dims, no hum, or buzz....very stable and reliable.

[Magnum]

It seems the PP alternator and the Stec starter are the best (and cheapest) upgrades. You really get something for your money.

[testwest]

+1 for Plane Power. No more "Low Voltage" lights flashing at me in the flare while landing at night (with the old 250W 12V landing light in the nose).

me likey, too

[jetdriven]

Same here.  Excellent product.  More output than the Prestolite unit and lighter as well.  More modern design. No low voltage light ever.  Just make sure the output terminal is torqued correctly.  Ours was not and it melted the output post off.  

[podair]

my Plane Power alternator has been rock steady at 14.1v for over two years, installed after my old generator ate up a couple regulators and finally gave up the ghost. Very happy with it.

However on the last couple of flights I had the low vol light on the ground then went off as vols ticked higher (voltmeter on the edm700) and small positive amps charge.

Last flight yesterday was more problematic. Voltage light on , amps slightly positive, volts steady but not increasing at 12.5v. In mid flight, I pulled the alt field breaker, vols ticked lower, then put breaker back in, zoom, up to 14.1v and steady throughout the flight.

Do I have a regulator problem?

Patrick

[jetdriven]

Check your output post nut on the alternator immediately. Ours did that and it melted the post and the wire off in flight.

[podair]

Oops... thanks for the heads' up! 

What exactly do I need to check? Did yours do that right after install or some time after?

[jetdriven]

The big wire going to the side of the alternator, check that for tighness at the end where it bolts to the stud.  While you are there check the small wire going to the back as well.   What happens is the nut on the stud gets loose, and the wire arcs to the post causing the alternator to intermittently not charge.  Finally the wire or the post burns through and no more charging.  We had a mechanic who installed it and didnt torque the nut. It started acting up  (low voltage light at idle, going out during runup) after about 3-4 hours. It failed completely in 32 hours.

[podair]

hurrah! problem fixed... alternator belt was slipping...

don't you love it when it is as simple as that?

still puzzled why it came back perfectly when I popped the breaker, but no joy on following flights, was getting very low positive amps and volts no higher than 12v

regulator and alternator working beautifully

[jkarch]

I just purchased a Plane Power AL12-P70 alternator for my 1981 M20J and my mechanic told me today that the alternator does not directly bolt in place of the ALY-8520 Kelly Alternator that was there.  Should I have bought the AL12-70 alternator?  Plane Power states the AL12-P70 is designed for the Mooney J model with Prestolite alternator, and that the AL12-70 is for 360 series engines.  The AL12-70 has a mounting boss, while the AL12-P70 does not come with the mounting hardware.  Did anyone else have similar issues?  Are there any other alternatives?  I'd hate to overhaul my existing  Kelly unit, only to have it break again sometime down the road.

 

Thank You,

 

Josh Karch

[KSMooniac]

I put a PP on about a year ago but can't remember the model # off the top of my head.  It bolted right in to my J with no issues that I can recall, and it came with the required hardware.  There is no way I would willingly put anything from Kelly on my airplane, and that is what drove me to the PP in the first place.

[jetdriven]

Same here. We have an AL-12P70 that replaced the crappy Kelly.   It bolts on like a car, a long pivot bolt on the engine end, and the bolt that goes in the bracket slot has safety wire.  simple.  Baffling needs to be closed in a little, but easy to do.

[larryb]

Went out to the plane (84 J model) today to install my brand new Plane-Power AL-12P70. Everything fine, until it didn't fit. I double checked all of the cross references, the old alternator was the correct model, new one was correct. The problem is that the tension arm (long bracket with slot) is too short on the new alternator. Looking at the pictures, you can see how the old alternator had 2 bolt options for the tension arm, the new alternator has one, and it's in a slightly different position. In addition, the distance between the shaft center and the pivot bolt is about 3/8" shorter on the Plane-Power alternator. Either a longer tension arm, or a shorter alternator belt would make this fit.

This was supposed to be a simple owner-performed project with A&P signoff. I called the A&P who came over and scratched his head also. He's done a couple before, not on a Mooney, and had no troubles. We left it that I would call Plane-Power in the morning and see what they had to say.

Did anybody else have any similar issues?

Thanks, Larry

[Alan Fox]

Put a pp on my old mousketeer , great product.... Havent put one on the Bonanza , as the Bo has a geared alternator that has no issues..... My mooney has the interav conversion , if it fails it gets a pp...

[N601RX]

Is the current belt the correct one?

[Alan Fox]

Is the current belt the correct one?

It cant be as the pulley on the pp has a much larger diameter...although the mounting seems to be different....

[larryb]

It cant be as the pulley on the pp has a much larger diameter...although the mounting seems to be different....

I assume belt is correct, but will verify. The old alternator, with the existing belt, seemed to fit fine. The tension bolt was about in the middle of the tension bar.

I think the pp is supposed to spin slower, hence the larger pully.

[carqwik]

+1 on PP Alternator here too....70A 24V installed on Alt 2...

[andrew]

Does anyone know if there is a 28V plane power alternator compatible with the M20K (TSIO-360-MB1)? I can't seem to figure out which would be the correct model and the Plane Power listing only suggests a 14V alternator for the M20Ks.

[Parker_Woodruff]

Does anyone know if there is a 28V plane power alternator compatible with the M20K (TSIO-360-MB1)? I can't seem to figure out which would be the correct model and the Plane Power listing only suggests a 14V alternator for the M20Ks.

I went through this and unfortunately there's not one available for us. You're probably stuck with a 28V Kelly setup. Mine was $595 from Quality, IIRC.

[DaV8or]

I'm another happy Plane Power customer!