[Lyle Swallows]

Hi All,

what size was the Alternator in the later model Talons/Phoenix A600's?

i have a 37amp Prestolite 8AR2169, i see later 51Amp became the standard?

i would like to eventually do an Electric water pump upgrade aswell as not worry about any charging at Idle or overcapacity issues with lights/avionics including a small electric heater blower fan robbed from an R22.

here are some graphs i've found for the 37Amp and 65amp 8AR series prestolite's

[Jared Hartzell]

I'm not 100% sure but the alternator I ordered from RotorX before they closed doors was a 65A leece neville alternator, that's what they were supplying at the time. I still have to rev up to about 2,200 rpm momentarily before switching the alternator on to get a good stable charge rate, then I can reduce back to idle and the voltage will hold at an appropriate 13.4v+.

[Lyle Swallows]

thanks Jared, the Leece Neville is the Prestolite so the above 65amp graph corresponds to you,

here is an article from 2002 "ROTORHEADS" regarding an alternator upgrade in regards to the high RPM excitation. doesnt appear to be available any longer but putting this up for others to see. i emailed the company with little expectations, i'll see if Robin has any 65Amp alternators available as the Rotorway Manual states they "tweaked" them internally... much like they stated for the water pumps aswell. maybe so we just didnt outsource them? haha.

no one ever seems to make a big deal about needing to run up to that higher RPM to engage the Alternator?

[Jared Hartzell]

Good question. If you ordered one online it'll probably behave the same way as mine from the factory... Just a guess, lol... They'll excite around 2,000 rpm minimum it seems but it takes a little more than that to get a good stable voltage going while the engine is warming up, so that chart is correct. Once it's going, you can reduce the rpm back down and let the engine warm up slowly while it charges.

Well, I've ran into some who weren't even aware that their battery wasn't charging at low idle on startup. I think it's something that's commonly overlooked often since the bulk charge voltage comes up once you get ready to takeoff anyway. But, with the amount of issues people have had with their charging systems and not noticing until it's too late, it seems that some don't check. This is definitely something that needs to be monitored in flight every once in a while and always checked after startup. If your battery isn't charging, that's a no-go.. Not checking has caused serious accidents in the past, some elect to install additional warning systems (not a bad idea!) but it should still be monitored.

[Tim Morris]

I have a Gammatronix 12V charging indicator installed.  Works great.   All over E-Bay.