Another Plane Power failure

[airguy]

After reading all about the various issues with them, and humming along happily like I had good sense with mine, you guys all get your chance at "told ya so"...

Mine failed this morning at 720 hours, enroute of course, loud obnoxious whine in the headset and less than half the normal output. I could see the voltage drop and battery discharge when I pulled back on the RPM or added load, I was getting maybe (generously) 25 amps out of a 60 amp alternator.

B&C primary will be ordered tomorrow. I'm sure glad I installed a backup B&C, it took the load just like it always has and didn't care, kept soldiering on.

[Foghorn]

I have the same set up but haven’t flown yet. I’d be happy with 725 hrs. Do you have a blast tube on the alternators? I’m not planning to have them but curious what others have done.

Thanks

[BillL]

Originally Posted by airguy

After reading all about the various issues with them, and humming along happily like I had good sense with mine, you guys all get your chance at "told ya so"...

Mine failed this morning at 720 hours, enroute of course, loud obnoxious whine in the headset and less than half the normal output. I could see the voltage drop and battery discharge when I pulled back on the RPM or added load, I was getting maybe (generously) 25 amps out of a 60 amp alternator.

B&C primary will be ordered tomorrow. I'm sure glad I installed a backup B&C, it took the load just like it always has and didn't care, kept soldiering on.

Likely the rectifier bridge, easily replaceable, but would only make a good backup. I will be happy with 720 hrs and plan for a replacement at 500 if it lasts that long. Since a B&C lasts twice as long as a good PP, the cost per hour is the same or less anyway. My 10-friend just replaced his at 500. We will take it apart and prepare it for a spare. He has a dual alternator system.

I did a complete teardown and report on a 520 hr PP, 60A that failed the rectifier bridge like yours. Everything else inside was good, bearings had good lube, even the brushes were only 25% worn to limit. Lots of life to go, just that one diode. A more robust diode bridge can be purchased in the aftermarket. 500 hrs is a good time to tear down and replace it. Clean interior and reuse the bearings, check brushes, and move on. The pulley bearing is available so it could be easily replaced, but the SRE bearing is special and not available outside Taiwan in quantities less than 5000.

Please take it apart and let me/us know if the slip ring end bearing has the expansion control rings on the OD of the outer race. That is the key to rebuildability as that bearing is not exported from Taiwan that I could find. Although, I got a quote directly from the NTN/Taiwan factory, although 5000/4999 is too many to have on hand.

[bjdecker]

Hopefully this question will result in some data being offered up.

Aside from the gold anodization, the B&C LX60 and PP AL12-EI60 look to be identical children of the same parent -- NipponDenso and Great-Big-Lucky-Industry-Factory #5.

I would love to understand B&C's engineering, supply chain, validation, testing, etc. that make their clone better than Hartzell's clone.

What're the differences, why are they different, what drove them to be different, how are those differences managed, validated and controlled.

Just asking before I drop $750 on another spinny-mechanical-thing...

Cheers!

[Raymo]

Originally Posted by Foghorn

I have the same set up but haven’t flown yet. I’d be happy with 725 hrs. Do you have a blast tube on the alternators? I’m not planning to have them but curious what others have done.

Thanks

PP requires a blast tube on the aft end of the alternator. Mine failed with < 300 hours. Replaced with externally regulated B&C. I think the externally regulated PP would also be fine but wasn't going to take another chance.

[airguy]

Originally Posted by Raymo

PP requires a blast tube on the aft end of the alternator. Mine failed with < 300 hours. Replaced with externally regulated B&C. I think the externally regulated PP would also be fine but wasn't going to take another chance.

That would definitely be part of my issue then - I did not install a blast tube on the Plane Power alternator. Still, it made it 720 hours.

I already ordered the B&C LX60 and external regulator this morning. Once and done.

[Marc Bourget]

I apologize if this was raised earlier, here, or in another thread, but I would like to see a correlation between Alt rpm at peak rpm and cruise and MTBF (mean time between failure).

Before I "woke up" I was going to install an alternator but found out that the pulleys I had available would spin the Alt over 9000 rpm at TO rpm of 2700.

Alternator output flattens out about 6000 rpm. I spoke to a guy over the phone and the data he provided gave 11,300 rpm for the alternator.

Short bearing life doesn't surprise me when they're spun that high.

Maybe a poll or equivalent?

FWIW

[rv8ch]

Originally Posted by Marc Bourget

I apologize if this was raised earlier, here, or in another thread, but I would like to see a correlation between Alt rpm at peak rpm and cruise and MTBF (mean time between failure).

Before I "woke up" I was going to install an alternator but found out that the pulleys I had available would spin the Alt over 9000 rpm at TO rpm of 2700.

Alternator output flattens out about 6000 rpm. I spoke to a guy over the phone and the data he provided gave 11,300 rpm for the alternator.

Short bearing life doesn't surprise me when they're spun that high.

Maybe a poll or equivalent?

FWIW

I installed a larger pulley on my alternator. No idea if it will make any real difference. https://www.summitracing.com/parts/PWM-185

[DanH]

Originally Posted by rv8ch

I installed a larger pulley on my alternator. No idea if it will make any real difference. https://www.summitracing.com/parts/PWM-185

Mickey, does that pulley slip right on the Plane Power 60 amp alternator?

[pilotkms]

Greg - sent u a PM.