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So does anyone else think it's time for a 30 amp alternator for the AeroVee? 20 amps just doesn't do it these days; not with a radio, transponder, ADSB, EFIS, lights, secondary ignition coils and Lithium batteries. I consider my setup rather average, with nothing fancy. But I have to make electrical decisions every time I fly.

I only use the secondary ignition for take off and landing. The coils pull too much power to use them in normal flight, unless you like watching your voltage drop during your entire trip. I always taxi with the secondaries off, else the battery drains quickly with the low RPMs. Even with the secondaries off, the LED strobe lights are all I can run, and even then my voltage tends to slowly drop. If I also turn on the LED position lights and the landing light all bets are off. Just watch the volts drop off!

The ONLY way I can keep the alternator charging the battery in flight is to turn off the secondary ignition.

As cockpits changed the AeroVee went from 10 amps to 20 amps. I think it's high time for 30 amps to become the standard.

If it’s at all possible, I’d buy the upgrade in a heartbeat as well! I constantly try to keep my panel spartan just so I don’t run into amperage issues. Having a 30 amp alternator would be very welcome!

When I recently rebuilt my AeroVee, I installed the Jabiru 20A stator and replaced the magnets. The Jabiru stator is wound differently to the Aeroconversions unit, but drops straight in. It solved my perennial low voltage issues.

There is a modification detailed on the Jabiru website to improve alternator output for the older models that suffered in the same manner as the AeroVee alternator. You don’t need 30A, just an honest 20A is more than sufficient.

RodgerC wrote:When I recently rebuilt my AeroVee, I installed the Jabiru 20A stator and replaced the magnets. The Jabiru stator is wound differently to the Aeroconversions unit, but drops straight in. It solved my perennial low voltage issues.

There is a modification detailed on the Jabiru website to improve alternator output for the older models that suffered in the same manner as the AeroVee alternator. You don’t need 30A, just an honest 20A is more than sufficient.

A web page and Google search didn't bring up anything. You wouldn't happen to know where on the web site to find that, would you?

I dont know what it would take to make it fit/work around the aerovee secondary ignition system but Great Plains sells a 35 amp alternator for the vw. You may be able to just replace the rotor if it fits or the stator and rotor without the Dihel accessory case. The jabiru solution seems interesting too.

Keith
#554

Hi Mike,

I read your post with interest. My setup is very similar to yours. MGL Discovery iEFIS, AHRS, magnetic compass, radio, transponder, ADSB, strobe, position and landing lights. However, when I fly my battery (lithium) is being recharged. When I used the Odyssey lead acid battery it worked the same. I cruise at around 3200 RPM. I do see a slight drain when I'm on the ground during taxi operations, and I do usually turn the strobes on.

That is very different from what you experience. I wonder what the cause could be.

-- Michael
OneX N169XE

XenosN42 wrote:I read your post with interest. My setup is very similar to yours. MGL Discovery iEFIS, AHRS, magnetic compass, radio, transponder, ADSB, strobe, position and landing lights. However, when I fly my battery (lithium) is being recharged. When I used the Odyssey lead acid battery it worked the same. I cruise at around 3200 RPM. I do see a slight drain when I'm on the ground during taxi operations, and I do usually turn the strobes on.

That is very different from what you experience. I wonder what the cause could be.

I don't typically cruise at 3200 rpm. 2950 to 3050 is more usual for me. I only get a positive charge if I turn off the secondary ignition. Even then it usually takes about 15+ minutes of flight before I will notice the charge going in the positive direction. 14.0v is as high as I get. Once I throttle back for a decent that number begins to drop.

RodgerC wrote:When I recently rebuilt my AeroVee, I installed the Jabiru 20A stator and replaced the magnets. The Jabiru stator is wound differently to the Aeroconversions unit, but drops straight in. It solved my perennial low voltage issues.

There is a modification detailed on the Jabiru website to improve alternator output for the older models that suffered in the same manner as the AeroVee alternator. You don’t need 30A, just an honest 20A is more than sufficient.

That’s really interesting. I didn’t know that was a drop in replacement. Has it been working well for you?

On most alternators, the claim is that they should not be run at more than 80% maximum continuous load for long periods of time, and if the same applies to our 20 amp alternators that means we shouldn’t ask more than 16 amps continuous. I’m not really sure if this applies to us or not, but if so, I can see where it would be easy to max out amp availability quickly!

Hi Mike F

The Jabiru stator (with new magnets) is perfect. It doesn’t have the epoxy “potting” that the AeroVee unit had, but otherwise it’s a direct swap. From memory, I had to length the wires but simply reused those from my original stator. It puts out much more charge than the original, but I’d suggest if you’re suffering low output, that you also check your magnet strength just in case they have become depleted due to contact with the stator. Especially if you had the issue that resulted in the SB because the stator’s mounting screws were bottoming out.

Cheers