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Alternator and belt

Plummit

Well Known Member
BPE IO540. I've got the prop off so I will replace the alternator and belt. The alternator spontaneously trips the 5 amp breaker for the field, usually when things like landing lights or other electrical switches are turned OFF. Any opinion on where to buy a replacement? I want new not rebuilt.

Also, the belt has 15375 and 422 stamped on it. There is little wear but I have 400 hours on the engine so I will replace it too. Is there a brand that is preferred?

-Marc
 
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Before spending the $$ for a new alternator, check the regulator-------assuming you have an external regulator.

B and C is a good source for these parts.

I used a belt from NAPA when I changed mine.

Also, thinking about the breaker tripping when you turn off a high load--------ground issues come to mind, also if you have a "crowbar" circuit it may be part of the problem, they are extremely sensitive.
 
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Also - a 5 amp breaker for the field may be a bit light - many builders use a 7.5 amp to avoid nuisance trips. That doesn't explain it tripping when loads are turned OFF however. Do you have a crowbar overvoltage device installed? If so, then I would start to suspect the regulator as mentioned above.
 
Built-in regulator and the Plane Power web site says my model, the AL12-E170C uses the "crowbar" device. I changed the breaker to rule out a weak unit. 5 Amp is the recommended size, but I thought about going to a larger breaker. The only thing that scares me is it sure looks like light wire going to the breaker. The $500 AS charges is nothing compared to the prop! :eek:

-Marc
 
Interesting poll. I noted that several respondents indicated no problem with Plane Power, but it does seem that B&C is regarded as "better".

So here's a little more info: When I bought my RV with 150 hours on the hobbs, the builder told me (and I experienced) that if the engine kicked back during starts, the circuit breaker would trip if the engine turned "backwards". I timed the mags, which were a a little off and eliminated the kickback. Still, the breaker would trip on occasion. At some point I realized that it was tripping when things were shut off. I would flip the flap switch up to retract the flaps and as soon as the motor stopped the breaker would sometimes, but not always, trip. Other times I would clear the runway and do my post landing check. Sometimes, but not always, the breaker would trip when I turned the landing lights off. Lately it seems that it is more frequent, but again, not always.

I've tried different things like have the rpm up a little higher when I turned stuff off, but nothing seemed repeatable. One day the breaker tripped when I did a mag check! I have 2 Bendix mags, there is no way they should make the Alt. breaker trip!

I'll see what the new alternator does and post the results, but it will probable be 3 weeks before my prop is back.

~Marc
 
My first step would be to replace the breaker with a 7.5A. I started with a 5A breaker and it would trip whenever the alternator was putting out more than 30+ amps. Breakers can also be defective and trip at lower than rated amperage. The CB or the voltage regulator is more likely than the alternator, given the symptoms you describe. Do you have an external VR? If so, I would replace that as well.

I am not a fan of the planepower alternator. I have read about way too many problems with it. I use an ND alternator ($25) and it has been without issue for 500 hours.

Larry
 
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I could be wrong, but isn't the design of the crowbar to trip that 5 amp CB that feeds the field if there is an overvoltage problem? regulator wacko? :rolleyes:
 
You said the engine kicked back, more than once.These events have been known to break gear teeth, so I can?t imagine they?re good for the alternator either. I find it hard to believe a small timing error was the cause; more likely a non-retarded mag is hot.
 
So I called Plane Power and spoke with a guy named Allen about the CB tripping when I turn stuff off. Allen thinks that there may indeed be a voltage spike when I shed load. He recommended that I try a slo-blow CB.

I called Stein and tried to order one and he doesn't carry such a thing. Moreover, he thinks that would probably be masking the real problem. He suggested I go back to Plane Power and try to get them to repair the alternator.

I called Allen back and hes says no dice, it's out of warranty. Fair enough, I ask him how much to overhaul it. They don't do that, The fix is to buy a new unit. Spruce is out of stock but A.E.R.O. will sell me one for $531.54. A few credit card numbers later and it's on the way. It's been an interesting morning.

-Marc
 
I called Allen back and hes says no dice, it's out of warranty. Fair enough, I ask him how much to overhaul it. They don't do that, The fix is to buy a new unit. Spruce is out of stock but A.E.R.O. will sell me one for $531.54. A few credit card numbers later and it's on the way. It's been an interesting morning.
-Marc
Yeah, that's what I and many others have found... apparently the result of PlanePower being sold to Hartzell Technologies a few years ago. When I got that response it added them to my “never again” list. Beyond that, a ridiculously high 26% failure rate in the first 250 hours also steered me away from PP. According to the poll referenced above, B&C only has a 2% failure rate, and automotive alternators only a 20% failure rate, in the same number of hours. Since the latter only cost me $28, that's the way I went. All my electrical gremlins went away when I ditched the PP for an ND and I've been happy ever since! Though I don’t need to, I could preemptively replace mine every year for 20 years and it would still be cheaper!
 
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So I called Plane Power and spoke with a guy named Allen about the CB tripping when I turn stuff off. Allen thinks that there may indeed be a voltage spike when I shed load. He recommended that I try a slo-blow CB.

I called Stein and tried to order one and he doesn't carry such a thing. Moreover, he thinks that would probably be masking the real problem. He suggested I go back to Plane Power and try to get them to repair the alternator.

I called Allen back and hes says no dice, it's out of warranty. Fair enough, I ask him how much to overhaul it. They don't do that, The fix is to buy a new unit. Spruce is out of stock but A.E.R.O. will sell me one for $531.54. A few credit card numbers later and it's on the way. It's been an interesting morning.

-Marc

That is the biggest frustration with PlanePower. Their alternators are simple, but the fact that a repair is to replace the unit is just ridiculous! That?s the kind of customer service that could kill a company, and they just flat don?t seem to care. I?m not saying it?s a junky alternator, although some would. I install them as primary all the time (mainly because they come with the firewall forward kit and they are internally regulated, thus easy to install).
 
ALT

If they don't repair why not take it to the auto repair shop ? Or by a new one to fit 1987 Suzuki Samurai for $100 that's the alternator my plane power used.
Bob
 
Don't assume any aftermarket or rebuilt alternator is the same quality as the OEM Denso it way resemble. Clearly from the stats we've seen here on VAF, they often aren't.
 
As has been already aluded to, the crowbar would appear to be tripping the breaker when you load shed.

If you are controlling the devices you are turning off with relays, than that may be the problem. A relay without a surpression diode will generate enough of a spike to trip a crowbar circuit. The fix is to add the diode across the relay coil. B&C regulators will trip when non-surpressed relays are de-energized.
 
On my RV-6, carbureted, I turn on my Facet pump for about 5 seconds before cranking the engine. If I have the alternator field turned on when I shut off the pump the field CB will sometimes pop, even a 7.5 amp CB. If I only turn on the battery it never pops. I turn on the alternator prior to cranking the engine. I replaced the first pump when it finally quit and the new one does it, too. Would a diode, as with a master or starter contactor, fix it? For now I just live with it.
 
On my RV-6, carbureted, I turn on my Facet pump for about 5 seconds before cranking the engine. If I have the alternator field turned on when I shut off the pump the field CB will sometimes pop, even a 7.5 amp CB. If I only turn on the battery it never pops. I turn on the alternator prior to cranking the engine. I replaced the first pump when it finally quit and the new one does it, too. Would a diode, as with a master or starter contactor, fix it? For now I just live with it.

Mike,
Not sure on the actual electronics in the cube pumps but it certainly wouldn't hurt to try by putting a diode across it.
 
As has been already aluded to, the crowbar would appear to be tripping the breaker when you load shed.

If you are controlling the devices you are turning off with relays, than that may be the problem. A relay without a surpression diode will generate enough of a spike to trip a crowbar circuit. The fix is to add the diode across the relay coil. B&C regulators will trip when non-surpressed relays are de-energized.

All devices are controlled by rocker switches. AFAIK the things that usually cause the CB to trip are NOT controlled by relays. Intestingly, Allen wanted me to take the alternator to Autozone or some other auto parts store to be tested. He also said that if i send it back they will test for free. That was what prompted my question about repair, which they don't do. I feel it would be a wasted of shipping $$$ to send it back or even take it to autozone if the fix it so buy a new one. I'm pretty sure the problem lies in the unit. We'll see.

-Marc

-Marc
 
I got the prop back on and balanced - All good now. We did the initial flight in VFR conditions, and I'm happy to report that the alternator field CB has not tripped once! I do all of the things that made it trip (when I turned stuff off))
and it appears that the problem is solved now. I'm thinking the alternator may have been bad from the start... I say "alternator" because it has a built in regulator that can't be serviced or replaced separately.

I may get it checked out as it would be nice to have a back-up in the hangar.

-Marc
 
My 60A PP alternator failed after 2 hrs (runaway tripping the field breaker). I took it to a local alternator repair shop. For $100 they replaced the blown rectifier and regulator. It is still working fine after 100hrs. If it goes again I will replace with the B&C. My backup B&C has had no issues from the start. FWIW.

Al
 
A lot of these type of problems seem to have been reported here. I think I'll have the PP removed from my FWF kit list. I'm all for integration but I think I'll go with the external regulator and crowbar.
 
A lot of these type of problems seem to have been reported here. I think I'll have the PP removed from my FWF kit list. I'm all for integration but I think I'll go with the external regulator and crowbar.

A wise move. With all of the PP alternator problems reported here, I don't understand why people keep buying them. I have 500 trouble free hours on my low cost ND alternator with external VR. I built my own crowbar with the pubslished circuit for $7 in parts. I believe they can be acquired pre-built for around $25.

Larry
 
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ND????

What is an ND alternator?

Is that short for Nippon Denso?

Would that be an external regulator as i have already purchased a Plane Power external regulator to fit my prestolite alternator only to find that my prestolite wont fit into my cowling. OUCH

Dave C.
 
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