Alternator Failure

[sbalmos]

I'm beginning to think alternator manufacturers are quickly overtaking primer/no-primer for the favorite religious argument topic.

[scard]

I'm also a B&C junkie, but can attest to the fact that their stuff isn't perfect. I'm currently doing battle with a my rebuilt $$$ B&C alternator that doesn't work. Good thing I had a NEW one on the shelf.

[N941WR]

The old engine had the ND Suzuki alternator and when I Super Sized my engine I thought I was doing a good thing by putting the Plane Power alternator on it. Not so, as it turns out. The reason for the change was that when I hit the trailer, it cracked the old alternator housing, along with a few other "minor" parts.

It turns out the one alternator shop in our little town is closed on weekends.

I might run out and buy the Suzuki replacement but for the life of me, I can't recall what bushings and fittings I need, so I doubt I will be able to salvage the trip I had planned today.

BTW, I had 440 hours on the alternator.

[C-FAH Q]

Eh

Originally Posted by Walt

I'm firmly planted in the B&C camp, I think they have the best alt/reg system out there hands down. I also don't recall seeing or hearing of any failures, although I'm sure there must be some because like Paul said, nobody is "perfect".

My B&C regulator crapped out after one year and a week before my airplane was to be picked up by its new owner!

[N941WR]

Originally Posted by scard

I'm also a B&C junkie, but can attest to the fact that their stuff isn't perfect. I'm currently doing battle with a my rebuilt $$$ B&C alternator that doesn't work. Good thing I had a NEW one on the shelf.

Scott, you and I think a lot alike. I was thinking of just ordering a new one and having this one rebuilt so it is ready for the next failure. Only that isn't going to happen due to the price. :O

[Mark Dickens]

Originally Posted by N941WR

The old engine had the ND Suzuki alternator and when I Super Sized my engine I thought I was doing a good thing by putting the Plane Power alternator on it. Not so, as it turns out. The reason for the change was that when I hit the trailer, it cracked the old alternator housing, along with a few other "minor" parts.

It turns out the one alternator shop in our little town is closed on weekends.

I might run out and buy the Suzuki replacement but for the life of me, I can't recall what bushings and fittings I need, so I doubt I will be able to salvage the trip I had planned today.

BTW, I had 440 hours on the alternator.

Bill, just wondering, do you think cooling is the issue? I have one of these alternators installed, although not flying yet and have been wrestling with the pros and cons of putting a blast tube on to cool the back of the alternator.

[David-aviator]

Originally Posted by Ironflight

And this is why I continue to have ND's on my planes. Don't get me wrong - B&C makes a good alternator, Plane Power Makes a good alternator...as does ND. But "good" is not the same as "perfect", and there are many posts and threads here on VAF about failures in all of them. My personal take after reading many, many cases is that the failures are usually brought on by mounting problems or cooling problems - not generally the fault of the alternator - but that does happen as well.

The difference with an ND is that you can pick up a replacement almost anywhere, even on a Friday night (or a Sunday morning at most autoparts stores). Since I travel a lot, and don't like to get stuck waiting on a new alternator to get shipped out, I like the "operational reliability" I get from the auto part alternator. Ideally, we'd be able to buy an lternator that never failed - and that would be worth the extra cost. But I have yet to see one liek that, so I go with what leaves me grounded the least.

I do believe the B&C is a slightly modified ND. I've had good luck with them on 2 previous airplanes, have the Plane Power on the 8 and am waiting for the shoe to drop.

I wonder what it is that kills an alternator on an airplane? They seldom fail on an auto. My Honda Pilot has 235,000 miles, I replaced the it at 140,000 just to be safe but it was still running well. I've read they typically last 175,000 miles which is about 3500 hours of operation.

[N941WR]

Could someone tell me how to wire the pins on the ND alternator? I don't have the plug and will use push on connectors.

[N941WR]

Originally Posted by N941WR

Could someone tell me how to wire the pins on the ND alternator? I don't have the plug and will use push on connectors.

Never mind, the wiring info came with the ND alternator. What doesn't come with the alternator is the correct brackets.

[BillL]

Originally Posted by David-aviator

I do believe the B&C is a slightly modified ND. I've had good luck with them on 2 previous airplanes, have the Plane Power on the 8 and am waiting for the shoe to drop.

I wonder what it is that kills an alternator on an airplane? They seldom fail on an auto. My Honda Pilot has 235,000 miles, I replaced the it at 140,000 just to be safe but it was still running well. I've read they typically last 175,000 miles which is about 3500 hours of operation.

Each application of an alternator is different. Each installation is different. Autos, trucks, tractors, etc have varying degrees of engineering validation (being kind) to ensure that they are operating within given envelopes. They have intimate access to the alternator suppliers that want the parts to live and will help ensure that happens. The experimental world does little of this. It seems B&C tries to do this in various ways, as does PP hopefully.

External factors: Thermal, vibration, Belt forces, operational cycles and then think about the range vibrations, g's frequency, directions, and the same for the other factors. Operating speed, revs per mile, etc.

Temperature limits (one time, cycles, and weight averaging) of the electronics would be reached sooner than a limit for the rotor or stator.

Components: List each component and consider what the limitations of each are in comparison to the listed external factors. This is a taste of why.

My opinion on negative factors for our birds:
bearings - high speeds and temperatures need premium lubricants - belt wrap is poor and needs higher belt tension. Increased temps for belt will shorten the belt and add to the bearing loads. ( worse but kinda rare - other things fail first)
Internals - vibration - the footprint for mounting seems narrow and the case attachment is likely very active - much more than an auto. ( seems to be the driver for the PP failures, affects internal wires, brushes etc)
Temperature - close proximity to exhaust pipes, but air flow wise should be better than auto with such high under hood temps, and high cooling system temps. If we actually knew the temps then they could be corrected. More installation than application. ( regulators/ rectifier bridge would be primary failures)