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Auto Alternators

Here's a better device for handling OV events.

http://www.periheliondesign.com/lovm.htm

That won't work with the alternators with internal voltage regulators.

Most avionics today can take over 32 volts. They have their own voltage Regulators built into the Avionics.

You can convert any internally regulated nippondenso into externally regulated and buy an external voltage regulator. Then you would have direct control over the field wire.
 
The main reason I went with an auto alternator is field replacement. If I am AOG somewhere due to the alternator, I cancatch a ride to the nearest autoparts store and be on my way in no time.

I agree. I didn't do it just for cost. It was a combination of availability, reliability, and cost, lifetime warranty, etc.

Aircraft alternators seem like such specialty items and so hard to source. When mine went out, there was no where locally where I could find a replacement. And the guy who rebuilds them takes 3 days to rebuild.

It was frustrating so I decided to go the automotive route. The super low cost and lifetime warranty were just a bonus. The main benefit was the immediate and easy availability.
 
Alt failure at 475 hours

I was heading to a big fly in yesterday and 120 miles out I get a warning. The voltage was showing 12.2. Check of field circuit breaker and alternator breaker were good. Cycled the Alt several times to no avail. Shed the load and landed to look for anything obvious... was so hoping for something like broken belt. Of course not.... everything looked good with no loose wires. So now it's looking like an alt failure. Took off again for home. Plenty of battery power in my APEX battery. I flew with master and battery off except for a few spot checks on the way. Navigation was with my stratux which thankfully I did have a 15000 mah battery pack with me to power it up. Also my iPhone was doing well on it's own. I couldn't get it connected the the stratux.

My alternator is the nippondenso unit. The one supplied with the FF kit from vans. 60 amp IR for the voltage. I'm NOT liking the prices or availability of PP/B&C products. After reading this entire thread, I LOVE the idea that if I'm off somewhere and have a problem, the solution is as simple as a trip to most any autoparts store... soooo.... I'm wanting to switch to an automotive alt.

Here are my questions.
1. Are automotive alternators internally regulated for voltage. Is it the same as aircraft only alternators. A straight change out with no additional wiring???
2. If I get one that is not internal regulated then I guess I'll need an external voltage regulator. If I need to add an external voltage regulator, do I use one for autos?
3. If I do need an external voltage regulator, is there anything else I'll need to do?

Just to quickly get the plane up again... I found an alternator repair shop that said they can overhaul it so I'll be taking it Monday. I still want to make the switch to automotive. I don't like the feeling of being held hostage to availability and high prices. Me and my plane are VFR only so I'm ok making the switch. From what I've read, if I were flying IFR I think I go with B&C.
Thanks in advance for any advice.
 
I was heading to a big fly in yesterday and 120 miles out I get a warning. The voltage was showing 12.2. Check of field circuit breaker and alternator breaker were good. Cycled the Alt several times to no avail. Shed the load and landed to look for anything obvious... was so hoping for something like broken belt. Of course not.... everything looked good with no loose wires. So now it's looking like an alt failure. Took off again for home. Plenty of battery power in my APEX battery. I flew with master and battery off except for a few spot checks on the way. Navigation was with my stratux which thankfully I did have a 15000 mah battery pack with me to power it up. Also my iPhone was doing well on it's own. I couldn't get it connected the the stratux.

My alternator is the nippondenso unit. The one supplied with the FF kit from vans. 60 amp IR for the voltage. I'm NOT liking the prices or availability of PP/B&C products. After reading this entire thread, I LOVE the idea that if I'm off somewhere and have a problem, the solution is as simple as a trip to most any autoparts store... soooo.... I'm wanting to switch to an automotive alt.

Here are my questions.
1. Are automotive alternators internally regulated for voltage. Is it the same as aircraft only alternators. A straight change out with no additional wiring???
2. If I get one that is not internal regulated then I guess I'll need an external voltage regulator. If I need to add an external voltage regulator, do I use one for autos?
3. If I do need an external voltage regulator, is there anything else I'll need to do?

Just to quickly get the plane up again... I found an alternator repair shop that said they can overhaul it so I'll be taking it Monday. I still want to make the switch to automotive. I don't like the feeling of being held hostage to availability and high prices. Me and my plane are VFR only so I'm ok making the switch. From what I've read, if I were flying IFR I think I go with B&C.
Thanks in advance for any advice.

Paul, do you have the plane power 60 A or an automotive alternator now?
Picture maybe?? Email sent.
 
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Direction of rotation may depend on how it's defined on engine vs alternator. If you define alternator rotation looking from the pulley end, it would be counter-clockwise. Anyone know which case holds?
snipped

Left side, right side, clockwise and counterclockwise are all determined from the point of view of the driver/pilot, seated at the controls. This holds true for all vehicles. Lycomings rotate clockwise as viewed by the pilot [from the rear] As Josh mentioned on page 3, FWD [sideways engines] still use the same convention. Rotation is viewed from what used to be the rear of the engine.

Charlie
 
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That dodge one is definitely added to my list though. Available new, its more modern, LOTS of amps, external regulator, and many folks say fan direction doesn't matter.

Josh, Those Dodge van alternators [page 2 post 16] are/were Nippon Denso units. Most newer ND alternators have internal fan(s). Most of the bigger ones have a fan at each end [internally], so rotation direction is not that critical. To get genuine ND quality, you need to either order a new alternator or a ND genuine re-manufactured unit. The ND remans are competitively priced. Most other rebuild brands are using made in China parts on the rebuild. The items where quality really matters are the bearings and the rectifier diodes. Brands like Delco, Bosch & Motorcraft also tend to use higher quality parts.

Charlie
 
Bill, I think it was plane power but not sure. The only docs I have were from vans in the FF kit. It said Nippondenso which I guess is the alt mfgr.
 
I only got 90 hours on a brand new, not rebuilt, Nippondenso alternator I installed on my RV-10 when I built it. It went out when I was far from home but I had plenty of battery power to get me home with a dual PC-680 battery set-up. I replaced it with a B&C alternator and ext regulator and never regretted the decision. On my RV-9A project was a new Air-tec alternator and Sky-tec starter. I replaced both with B&C products. I sold the pulled units to help offset the cost of the B&C set-up. No one here wanted the Air-tec so I sold it on ebay for next to nothing. Oh well, someone got a good deal. I know there are a lot of people on this forum who have had good luck with automotive alternators so I am not bashing the idea of using one, just sharing my experience.
 
I only got 90 hours on a brand new, not rebuilt, Nippondenso alternator I installed on my RV-10 when I built it.snipped
I know there are a lot of people on this forum who have had good luck with automotive alternators so I am not bashing the idea of using one, just sharing my experience.

David,
What model ND alternator [or what year/model car] failed on you? One thing I forgot to mention on the last 2 posts. The 1995 Dodge ND alternator has a serpentine belt, rather than the OP's requested Vee belt pulley. Vee belts were phased out by the late 1980s on cars. So basically you can buy an alternator for an early 1980s car, with the right pulley & an external regulator. It will be hard to find a replacement alternator on short notice, as few of these cars are still on the road. Your other choice is a newer, more modern ND alternator, most of which are internally regulated and which all have pulleys for a serpentine belt. The mid 1990s to early 2000s Dodge trucks offer an alternator that stores still stock and has an external voltage regulator [it's built into the truck's engine computer aka PCM].
Changing the pulley is a 2 to 3 minute job, if you have a 1/2" impact gun [pneumatic or electric] to remove the mounting nut. It has been recommended on past threads to install a 4" diameter Vee belt pulley, rather than the 2 - 2.5" Vee belt pulleys that came on the old models. The advantage of the larger pulley is that it compensates for the added alternator RPM due to the large pulley on the Lycoming flywheel. Most car engines have crankshaft pulleys of 5"- 6.5" diameter. Going from memory, I believe our Lycoming pulleys are around 9.75" in diameter. [I don't have the reference materials on this computer to look that spec up.] Using the smaller alternator pulleys with a Lycoming ensures that the alternator spins much faster than it does on a car. That extra speed helps charging while you taxi, but wears your bearing & brushes out faster in cruise and climb flight. The larger diameter Vee belt pulleys are available at automotive hot-rod shops. For ND or ND clone alternators, you need a pulley with a 15mm hole for the shaft. The downside of the larger pulley, is possible cowl clearance issues, depending on where you mount the alternator. The clearance issue is more common on the tightly cowled RV 3s & 4s.

Charlie
 
I've been running a Honda alternator with external regulator on my RV6, I installed it in 1997 and haven't had a problem with it. I live in Michigan so it isn't around any extreme heat very often.
 
Do you really need a larger diameter pulley on the alternator?

Car engines can run more twice the rpm of an aircraft engine.
 
Do you really need a larger diameter pulley on the alternator?

Car engines can run more twice the rpm of an aircraft engine.

Need?? If your alternator works with the small pulley you don't "need" a larger one. However, your alternator will last longer with a larger pulley. I knew it would not take long for someone to ask your question.
While modern auto engines have redlines of 5,500 to 7,500 RPM, those engines only visit those speeds for mere seconds at a time. The average V-8 powered car only turns about 2,200 RPMs to do 70 MPH in top gear. It's doing so with a crankshaft pulley of about 6" diameter.
Asian 4 cylinder engines might turn 3,000 RPM at the same speed, but have 4.5" diameter crankshaft pulleys. Your Lycoming is going to run 2,400 to 2,500 RPMs for most of it's life.
Cars use small alternator pulleys due to the high electrical loads placed on them during low RPM operations. A car up north during the winter is running the heated rear glass [20 - 30 amps], the heater [4 -15 amps] lights at night [12 amps] ignition and fuel injection [12 amps] plus other items. Auto engines speed most of their lives at 700 to 1,800 RPMs.

Charlie
 
Do you really need a larger diameter pulley on the alternator?

Car engines can run more twice the rpm of an aircraft engine.

The Plane Power has a 2.75" pulley & runs 9570RPM @ 2700 engine RPM. The bearings/grease are rated for 15,000.
 
The Plane Power has a 2.75" pulley & runs 9570RPM @ 2700 engine RPM. The bearings/grease are rated for 15,000.

I would imagine that plane power uses higher quality bearings and parts than your average budget rebuilt. The engine pulley on most of the 4-cylinder Lycoming engines that we use is 9.75" in diameter. That's quite a bit bigger than your average car engine crankshaft pulley. Most of the Nippon Denso alternators converted for use on our engines use a 2.5 inch diameter pulley. That gives 10,530 alternator RPM at 2700 RPM.
Charlie
 
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Most auto alternators reach full output at 6-7000 rotor rpm. No need to spin them any faster than this continuously. Some car stuff will reach 14,000 rpm at redline but needs to be that way to supply enough amps at idle for the high electrical loads they have. Highway cruise, 70-80 mph, they are seeing 5000-7000 rpm in most cases.

Bigger pulleys extend bearing and brush life on aircraft. If you have the cowling clearance, not a bad idea.
 
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snipped Highway cruise, 70-80 mph, they are seeing 5000-7000 rpm in most cases.

Bigger pulleys extend bearing and brush life on aircraft. If you have the cowling clearance, not a bad idea.

Ross just to clarify, you're 5000 to 7000 RPM quote above is referring to alternator RPM correct?

Charlie
 
David,
What model ND alternator [or what year/model car] failed on you? One thing I forgot to mention on the last 2 posts. The 1995 Dodge ND alternator has a serpentine belt, rather than the OP's requested Vee belt pulley. Vee belts were phased out by the late 1980s on cars. So basically you can buy an alternator for an early 1980s car, with the right pulley & an external regulator. It will be hard to find a replacement alternator on short notice, as few of these cars are still on the road. Your other choice is a newer, more modern ND alternator, most of which are internally regulated and which all have pulleys for a serpentine belt. The mid 1990s to early 2000s Dodge trucks offer an alternator that stores still stock and has an external voltage regulator [it's built into the truck's engine computer aka PCM].
Changing the pulley is a 2 to 3 minute job, if you have a 1/2" impact gun [pneumatic or electric] to remove the mounting nut. It has been recommended on past threads to install a 4" diameter Vee belt pulley, rather than the 2 - 2.5" Vee belt pulleys that came on the old models. The advantage of the larger pulley is that it compensates for the added alternator RPM due to the large pulley on the Lycoming flywheel. Most car engines have crankshaft pulleys of 5"- 6.5" diameter. Going from memory, I believe our Lycoming pulleys are around 9.75" in diameter. [I don't have the reference materials on this computer to look that spec up.] Using the smaller alternator pulleys with a Lycoming ensures that the alternator spins much faster than it does on a car. That extra speed helps charging while you taxi, but wears your bearing & brushes out faster in cruise and climb flight. The larger diameter Vee belt pulleys are available at automotive hot-rod shops. For ND or ND clone alternators, you need a pulley with a 15mm hole for the shaft. The downside of the larger pulley, is possible cowl clearance issues, depending on where you mount the alternator. The clearance issue is more common on the tightly cowled RV 3s & 4s.

Charlie

The one for a 1987 Suzuki Samaria is what I used. Even had a blast tube on the built in regulator to keep it cool.
 
Rebuilt alternator installed

My 7A is now equipped with an auto alternator. It cost $91.00! The Lester number... (still not sure what that means but it is important!)... is 14684... thanks William Lane! It was literally a drop in replacement for the original Vans alternator that came in the FF kit.

Why did I switch to auto?

I was 120 miles from home when my alt crapped out.
If I would of ***HAD*** to get a PP or B&C alternator, First it would be at the very least $500.00 bucks PLUS shipping to wherever I might be. Second the time wasted waiting on its arrival. When this happened to me two days ago I felt like I was being held hostage.

Now... same scenario. With a couple borrowed tools and bumming a ride to an auto parts store... EVEN ON A SUNDAY... my alternator will most likely be in stock! In another hour I'll have the new one installed, drank a coke, used the bathroom and be ready for take off.

I've read the threads regarding failure rates and quality. I'm VFR only so I'm comfortable not spending 7 or 800 dollars. Even the top brand seems to fail at some point. Even if you get 1000 hours that's great but from reading these threads doesn't seem to be the norm. I got 475 hours from the Vans supplied one and a replacement from them was going to be $475.00 plus shipping and don't forget about the down time. I went with a hundred dollar unit available NOW and If I get anything close to 300 hours I think I'll be happy. The interesting thing is it looks EXACTLY like the one I removed.

The last couple days I've learned ALOT about alternators. William Lane from here and Savvy Aviations video by Mike Busch really helped!
 
I went with a hundred dollar unit available NOW and If I get anything close to 300 hours I think I'll be happy. The interesting thing is it looks EXACTLY like the one I removed.

The last couple days I've learned ALOT about alternators. William Lane from here and Savvy Aviations video by Mike Busch really helped!

Don't be surprised if your "cheap" alternator goes a lot further than 300 hours. :)

However...I usually drop the belt off the alternator pulley during condition inspection to I can spin the the pulley and check for noisy bearings. I found loose bearings one time during the past twenty years.
 
No need to make one from scratch

Where do you get a 4" alternator pulley?

I was just thinking of turning my own, maybe out of titanium :)

This one comes with a bushing for smaller sized alternator rotor shafts. It's also a few dollars cheaper. See

https://www.jegs.com/i/Powermaster/713/182/10002/-1

FYI, many years ago, Vans alternators came with a note stating that you could modify the pulley from the A.I.R. pump [smog pump] from a late 1970s Camero. I believe all you had to do was to open up the hole for the rotor shaft a bit. The P/N for that smog pulley is 14087007TAY. Knowing GM, that pulley was probably used on a lot more GM models. The smog pulley is 4.25" in diameter, rather than the more common 4".

Charlie
 
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I'm using the 4" Summit pulley on my 70 amp Toyota Camry (ND) alternator. I chucked the pulley in my lathe and removed a bunch of metal to lighten it up, and removed the OD down to the top of the belt (it's a "deep groove", high RPM unit). With EFI and all the other goodies, I pull A lot of electrical power. To those concerned with slowing the alternator down too much at approach speeds, I can report that my auto alternator puts out everything I need. - I have seen 50 amps output at 700 engine RPM at times. That's plenty for me!

As an aside I have run this unit both with the stock internal regulator as well as converted to external regulation. No perceptible difference in performance.
 
From the information I have, primarily the alternator spec sheet I ran the numbers regarding alternator pulley size & rpm and alternator amp outputs at each. These numbers are based on my 55 Amp alt.

1. With engine RPM at 800 and a 2.75 inch alternator pulley, the alternator revolutions are about 2837. The alternator is putting out close to 40 A.

2. With engine RPM at 2400 and a 2.75 inch alternator pulley, the alternator revolutions are about 8507. The alternator is putting out 55 A.

3. With engine RPMs at 800 and a 4 inch alternator pulley, the alternator revolutions would be 1950. The alternator would be putting out about 31 A.

4. With engine RPM at 2400 and a 4 inch alternator pulley, the alternator revolutions would be 6685. The alternator would be putting out 55 A.

Sooo, if one goes to a 4" alt pulley, at close to idle power/landing phase of flight, the alternator outputs would be in my case about half. Like I've mentioned, I'm VFR only so not an issue for me. If you are IFR coming in through the clouds and have low engine/alt rpms on final approach make sure your full current demands can be met with the larger alt pulley. Yesterday when I taxied out after replacing the alternator, (old one was 60 amps), at idle power I turned everything switch in the cockpit on to see if it could handle it which it did. I know a couple years ago it would not have because I had high current draw lights. Now I'm nothing but LED's and they take almost nothing!

EDITED: I am a numbers kind of guy and can't help thinking of weird stuff sometimes. It makes perfect sense that the life of an alternator with a 2.75 pulley would be shorter. The "extra" rpms in a one hour flight are something like 109320! And for one hundred hours of flight time the extra alternator rpm are in the neighborhood of 10,932,000!!!
I figured the alternator I just removed having lived a 475 hour life turned about 237,000,000 RPM's over its life. I know useless information but interesting.
 
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Thanks to everyone for the replies and links. Really appreciate the report of outputs. Full IFR panel and SDS EFI I'll need a bit of juice at all times
 
....ran the numbers regarding alternator pulley size & rpm and alternator amp output....

1. With engine RPM at 800 and a 2.75 inch alternator pulley, the alternator revolutions are about......
Keep in mind not all ring gear pulleys are same diameter.
 
I have the older small 7....something inch flywheel pulley. The numbers worked out perfect with the stock alternator pulley.

In cruise, with efis, comm, adsb, mp3, tablet, and strobes on, I only use about 8 amps. If I turn on all the lights, including the HIDs, it gets up to around 12-13.
 
And the beat goes on......

I debated over this for years. I watched as Plane and Power nosedived from top drawer to lower shelf.

I gave up and went with the B&C alternator and a Plane power regulator(ordered previously)

Expensive, say 450 Cdn i think i like the fact it is aviation oriented, the system has crowbar and overvoltage protection

A friend here had a surge go through his Cessna Skymaster and $40K later he restored the panel to service. One needs good protection.

Good luck and from what i found out, the auto alt. would work and has for many, i just chose the more expensive but i hope tested reliable B&C.

Dave
 
I have a crowbar OV module on my internally regulated auto alternator as well. The alternator B lead is connected to the buss via an 80amp contactor. The contactor coil is powered from the main buss using what would normally be the field breaker. The crow bar connects the breaker to ground. If a OV occurs, the crowbar trips the breaker and disconnects the alternator from the buss. The current flyback would likely kill the internal regulator, but it must have had a fault anyway to cause the OV.
 
A friend here had a surge go through his Cessna Skymaster and $40K later he restored the panel to service. One needs good protection.Dave
Scary. $40K. Nice panel. What did he blow? I ask because most modern avionics runs on 10 to 30 volts and they have their own OV protection. Old school avionics were virtually unprotected... power went right in the board where the semiconductor had low voltage ratings (capacitors, transistors, diodes, IC's). Avionics have improved from the "classic" stuff.

I have a crowbar OV module on my internally regulated auto alternator as well. The alternator B lead is connected to the buss via an 80amp contactor. The contactor coil is powered from the main buss using what would normally be the field breaker. The crow bar connects the breaker to ground. If a OV occurs, the crowbar trips the breaker and disconnects the alternator from the buss. The current flyback would likely kill the internal regulator, but it must have had a fault anyway to cause the OV.
That's how I did it, but my Alternator is only 40 amps and run a 50 Amp CB. The max draw of the plane night is no more than 25-30 amps (LED's are amazing). With that said I have a OV relay on the Aux bus as well to isolate the electronic ignition and run from Aux battery only.
 
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From the information I have, primarily the alternator spec sheet I ran the numbers regarding alternator pulley size & rpm and alternator amp outputs at each. These numbers are based on my 55 Amp alt.

1. With engine RPM at 800 and a 2.75 inch alternator pulley, the alternator revolutions are about 2837. The alternator is putting out close to 40 A.

2. With engine RPM at 2400 and a 2.75 inch alternator pulley, the alternator revolutions are about 8507. The alternator is putting out 55 A.

3. With engine RPMs at 800 and a 4 inch alternator pulley, the alternator revolutions would be 1950. The alternator would be putting out about 31 A.

4. With engine RPM at 2400 and a 4 inch alternator pulley, the alternator revolutions would be 6685. The alternator would be putting out 55 A.

Sooo, if one goes to a 4" alt pulley, at close to idle power/landing phase of flight, the alternator outputs would be in my case about half. Like I've mentioned, I'm VFR only so not an issue for me. If you are IFR coming in through the clouds and have low engine/alt rpms on final approach make sure your full current demands can be met with the larger alt pulley. Yesterday when I taxied out after replacing the alternator, (old one was 60 amps), at idle power I turned everything switch in the cockpit on to see if it could handle it which it did. I know a couple years ago it would not have because I had high current draw lights. Now I'm nothing but LED's and they take almost nothing!

EDITED: I am a numbers kind of guy and can't help thinking of weird stuff sometimes. It makes perfect sense that the life of an alternator with a 2.75 pulley would be shorter. The "extra" rpms in a one hour flight are something like 109320! And for one hundred hours of flight time the extra alternator rpm are in the neighborhood of 10,932,000!!!
I figured the alternator I just removed having lived a 475 hour life turned about 237,000,000 RPM's over its life. I know useless information but interesting.

Best understood as revolutions over it's life.
 
Best understood as revolutions over it's life.
Good point, but these auto alternators are able to run up to 9000 rpm all day, but logic would say it will live longer at 6000 RPM. With that said how many ND or ND clone alternators die because of bearing failure? On the pro side, higher RPM makes more power and more cooling air.

If you use a small diameter Lyc ring gear pulley, there are different diameters, and a large 4" alternator pulley, at lower engine RPM's (approach) your alternator will have below rated output. Is that a big deal? Not really if your alternator is making enough power even below full rated output.

With all the state of art avionics and LED lights most RV's have lower electrical system demand than in the past. However I don't underestimate builders to load the plane with electric heated seats or other high draw items.
 
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Good point, but these auto alternators are able to run up to 9000 rpm all day, but logic would say it will live longer at 6000 RPM. With that said how many ND or ND clone alternators die because of bearing failure? On the pro side, higher RPM makes more power and more cooling air.

If you use a small diameter Lyc ring gear pulley, there are different diameters, and a large 4" alternator pulley, at lower engine RPM's (approach) your alternator will have below rated output. Is that a big deal? Not really if your alternator is making enough power even below full rated output.

Apparently quite a number of clone alternators do suffer premature bearing failure as a result of installing **** bearings during manufacture or rebuild.

From looking at test charts, your average ND alternator will produce about half its rated amperage at around 2000 rotor rpm. If we assume 1300 rpm on final and even a 2 to 1 pulley ratio, that means your 60 amp model can still jam out over 30 amps which is probably fine for most applications.
 
Apparently quite a number of clone alternators do suffer premature bearing failure as a result of installing **** bearings during manufacture or rebuild.

From looking at test charts, your average ND alternator will produce about half its rated amperage at around 2000 rotor rpm. If we assume 1300 rpm on final and even a 2 to 1 pulley ratio, that means your 60 amp model can still jam out over 30 amps which is probably fine for most applications.
Not all clones are the same. I found the ones from Taiwan were better than ones for China, but that was 10 years ago.

If you can get a new ND that is best, but most of the genuine Japan made small ND's for cars are no longer in ND production. However I got a new 40 amp ND made in Japan, for a kabota tractor. It was old new stock and got it cheap. Even at 20 amps it makes enough for my needs except right after start when battery draws higher charge amps for a few seconds. So I delay turning on all the bells, whistles and lights a few seconds right after start, until the battery charge settles down.

I have a small Lyc ring gear puller now, so my alternator RPM's are lower at engine idle. However I need to upgrade to a cool SDS billet ring gear pulley to fit dual SDS EI hall effect sensors. :D
 
PP 60A Bearings - FYI

I have been gathering a lot of information on the PP bearings, and bearings in general for alternators. The brand of the PP bearings is NTN, but made in a TPI plant in Taiwan. TPI makes branded bearings for you if you want a Smith bearing. The plant uses Japanese bearing steels, and has a good range of greases. I believe this is one.

Speeds: NTN literature has a nomograph for bearing grease life, the limiting factor for us. Even operating at 2700 Engine/9600 alt RPM, the bearing life at rated load is in excess of 15,000 hrs. Don't worry about the speed.

The bearing loads for the PP are quite low relative to the rating.
 
Here's a better device for handling OV events.
http://www.periheliondesign.com/lovm.htm
Look at the schematics George.
I see, should have been clear. So he has two schematics.

The first is put his OV switch on the ON/OFF lead to the IR alternator. It may work fine, but don't like it. ;) I have seen people do this, and when they "tested it", bad things happened, the least of which is they fried the internal VR that was OK before the test. Or when they turned the alternator OFF nothing happened. However others swear by the ON/OFF IGN lead working like a charm to turn the alternator OFF and ON while under load. It is not what that lead was made for however. It is to reduce parasitic drain when ignition is off and alternator is stopped. When you turn on the IGN (car) the alternator is not turning. In an emergency OV condition it may work. I just don't trust it.

The second idea is a mighty contactor (relay). I thought of that. My criticism is minor. First is weight, and second 2 amps to hold it closed (although you could use a latching contactor). If you "test it" and kill the B-lead the alternator will not love it. Will it damage it? Don't know, may be, may be not. The solution is DON'T TEST IT. It is also a single point failure, but I suppose you could reset it (if you did not kill the alternator). But if you have an OV why would you want to reset it. It will work, but the CON for me is the weight and continuous draw of the contractor. Not bad just overkill may be. I like perihelion designs and gadgets, definitely cool good ideas.

The other way is put a B-lead circuit breaker in the panel with an OV crow bar. If you get OV, the CB will trip. Forget the crow bar and pull it manually. This does not jive with the tend to go with fuses remotely mounted. The CB is re-settable, but why would you want to at that point. This is similar to the perihelion relay minus the weight and current drain. All these ideas are brute force. Is OV really that bad? How many cars have OV? How many cert airplanes with old power systems (mostly from automotive industry) have had OV (some did and argue more than modern IR alternators). OV matters more with electrically dependent ignitions we have today, but you can isolate the EI. However on the other hand as mentioned before, most glass cockpits have filtered power supplies that run on 10 to 30 volts.
 
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Concerning bearing life, I know of some situations where an OH unit was procured from the local auto parts emporium and opened up. The inner seal on the front bearing was missing, exposing the guts to the dust and grit. Coincidence?
 
I have been gathering a lot of information on the PP bearings, and bearings in general for alternators. The brand of the PP bearings is NTN, but made in a TPI plant in Taiwan. TPI makes branded bearings for you if you want a Smith bearing. The plant uses Japanese bearing steels, and has a good range of greases. I believe this is one.

Speeds: NTN literature has a nomograph for bearing grease life, the limiting factor for us. Even operating at 2700 Engine/9600 alt RPM, the bearing life at rated load is in excess of 15,000 hrs. Don't worry about the speed.

The bearing loads for the PP are quite low relative to the rating.

Good to know. Is the the case on current build alternators? Can you trace how far back this is the case? We have seen several reports here where bearings were on their way out in less than 100 hours. Would be nice to know where those ones were made.

For genuine Denso, you can go here and type in your zip to find a dealer close to you: http://densoautoparts.com/where-to-buy.aspx#
 
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Alternators for High Priced Avionics

When working through the options for alternator selection I came the conclusion there were two clear choices in ?standard? offerings ( B&C and Planepower) and the alternate route of selecting a suitable automotive offering and doing the engineering. The second option seemed a much less costly solution but could be problematic in time and all the development work needed to ensure performance and reliability. B & C seemed to have their act together more than Planepower based on forum postings so I am going with B & C. I also purchased the B&C grounding terminal block. Whereas the B&C alternator and regulator designs showed clear evidence of precision mass production engineering techniques being used the terminal block was an entirely different animal - tag strips soldered on to a brass plate - much more of a hobbyshop product. It got me thinking. Is B&C principally a rebranding operation that has the capability to inspect and relabel selected automotive parts or a true developer of electrical components? I dont know the answer to the question - I strongly suspect the former but they have done the work to select suitable components and the development work to build a reputation for reliable operation so I dont feel bad about paying the freight to purchase parts from them. I did rework the terminal strip to remove the excess solder, attach the tag strip to the brass plate with four 426-4 rivets and reflow the solder to make it look presentable. Using solder to mechanically attach anything in a vibration environment is always a bad plan. I would be curious to know if others have had similar thoughts about which particular brand of alternator and regulator B&C is using as the basis for their product line. Personally I feel more at ease if they are using a rebranded automotive product. Product variability will be lower and reliability higher.

KT
 
Parts Quality Is Only Part of the Equation

Good to know. Is the the case on current build alternators? Can you trace how far back this is the case? We have seen several reports here where bearings were on their way out in less than 100 hours. Would be nice to know where those ones were made.

For genuine Denso, you can go here and type in your zip to find a dealer close to you: http://densoautoparts.com/where-to-buy.aspx#

The best of components can be defeated by an unskilled or apathetic work force assembling the alternators. Every week contains a Monday morning and a Friday afternoon!

Charlie
 
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The best of components can be defeated by an unskilled or apathetic work force assembling the alternators. Every week contains a Monday morning and a Friday afternoon!

Charlie

True, but poor quality parts will fail prematurely no matter who assembles them. I've seen enough "offshore made" junk bearings installed on many devices fail in 1/100th the normal lifespan of Timken, SKF, Koyo etc. brands.

I'm not picking on any particular brand but the PP stuff clearly went quickly downhill once it was outsourced. Hopefully Hartzell will be bringing the quality and durability back up to where it was before that move.

The automotive rebuild world is often guilty as well, replacing the quality OEM bearings, brushes and rectifiers with cheap junk- often with the same result.
 
Good to know. Is the the case on current build alternators? Can you trace how far back this is the case? We have seen several reports here where bearings were on their way out in less than 100 hours. Would be nice to know where those ones were made.

For genuine Denso, you can go here and type in your zip to find a dealer close to you: http://densoautoparts.com/where-to-buy.aspx#

Ross, I have no way of knowing what the production changes might be on the PP alternators. You know how hard it is to get facts. The country of manufacture is laser printed on each bearing or on the seal. People with failed PP parts need to report that for us to know.

For auto alternators, what would we do if we knew? Isn't that why we try to buy a reputable brand?

EDIT - Do we know that the source manufacturer was changed with the Hartzell acquisition of PP or just happened to have a production problem? The H rep reported here the changes found for the problems, and I heard the exact same thing from the Hartzell guys at OSH this year. If VAFers want to send me some of the failed PP 60A units I will take them apart and report the finding. A VAF member sent his and it provided a huge about of information. I went down a rabbit hole with the bearing replacement, but that is about to it's end.

Edit #2 - That densoparts link is not to a denso company. I called them. Great site, and reference though.
 
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Bob, How much does it weigh?

Charlie

The small frame 35-45 amp ND alternators are about 7 lbs without brackets. You will not get much lighter. The one in questions has A LOT of hot air greatest latest efficiency hype... OK. It's a copy of a 1990's ND. If it is China I would stay away. The Taiwan made clones were better but cost more. This is seriously cheap for a new alternator... even a clone. Buy it, fly it and report back...
 
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B&C Alternator equals Denso?

Looking at the link for the alternator used by Bob it seems pretty clear that the B&C alternator is from the Denso stable - just have to find the particular model number for the equivelent part. Now have to also track down the regulator and see if there is an equivelent version of the regulator with overvoltage protection. Objective here is to find alternative sources for alternators and regulators for field replacement/repairs.
KT
 
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