rebuild Ample Power 105A

[Hayden Watson]

I have an Ample Power 105A alternator that has given over a quarter of a century of faithful service. I would like to extend this with some preventative maintainance like brush and bearing replacement. I called a couple of "Auto Electric" shops to see about getting it done and they just said, "We do not rebuild, we chuck them an get new.".
Way back when I was taking my diesel mechanics course on college, I rebuilt several alternators and starters and know that it is not hard. Any suggestions as to where to get the parts and how to ensure that I order the correct ones?

 

[Maine Sail]

I have an Ample Power 105A alternator that has given over a quarter of a century of faithful service. I would like to extend this with some preventative maintainance like brush and bearing replacement. I called a couple of "Auto Electric" shops to see about getting it done and they just said, "We do not rebuild, we chuck them an get new.".
Way back when I was taking my diesel mechanics course on college, I rebuilt several alternators and starters and know that it is not hard. Any suggestions as to where to get the parts and how to ensure that I order the correct ones?

Other than diodes and the stator and Rotor that alt is about as easy to rebuild as it gets.. as long as the stator/rotor and diodes are still good a brush holder, front bearing and rear bearing are all you'll need. Plenty of good shops in the Seattle area..try Ballard Electric or Romaine.. The Ample alts were based on a Delco 10DN. You definitely won't find a stator but you can find a "will fit" rotor. Just be sure to test it after rebuild to ensure it performs the same..

My business was building a much improved version of the Ample alts after they closed so we know them inside and out.. About three weeks before my stroke our stator/rotor winder closed their doors (last one in the US) so performance 10DN frame alts are done. All you can get now are cheap Chinese stators/rotors..

 

[kloudie1]

Bearings are going to be standard parts, I think. The brushes are going to be tougher to find, but if ya take them out and take them to an electric motor shop, they might be able to do a match.

 

[Maine Sail]

Bearings are going to be standard parts, I think. The brushes are going to be tougher to find, but if ya take them out and take them to an electric motor shop, they might be able to do a match.

10DN brush holders are easy to find. However high copper content what Ample and CMI used will be hard. It requires a brush holder then making your own high copper brushes.. Not difficult but difficult to source if you're not in the industry..

 

[Hayden Watson]

10DN brush holders are easy to find. However high copper content what Ample and CMI used will be hard. It requires a brush holder then making your own high copper brushes.. Not difficult but difficult to source if you're not in the industry..

Thanks Rod.

My alternator is working perfectly so no need to replace the rotor or stator. I just want to keep it that way. I do not have a commutator lathe but am guessing that I can just clean it up with some emery cloth, yes?

If I cannot find the high copper brushes, would it be an except able alternative to put them on my annual or bi-annual maintenance to just remove and replace on a schedule? Something like after so many engine hours, replace brushes.

I am also looking at being able to isolate the grounded brush so that I can install a PWM control to be able to dial in the output I want. Can you shed any insight into what I would need to do or at least provide a photo of what I will find inside at the brush holder?

 

[Hayden Watson]

Other than diodes and the stator and Rotor that alt is about as easy to rebuild as it gets.. as long as the stator/rotor and diodes are still good a brush holder, front bearing and rear bearing are all you'll need. Plenty of good shops in the Seattle area..try Ballard Electric or Romaine.. The Ample alts were based on a Delco 10DN. You definitely won't find a stator but you can find a "will fit" rotor. Just be sure to test it after rebuild to ensure it performs the same..

My business was building a much improved version of the Ample alts after they closed so we know them inside and out.. About three weeks before my stroke our stator/rotor winder closed their doors (last one in the US) so performance 10DN frame alts are done. All you can get now are cheap Chinese stators/rotors..

Thanks Rod.

My alternator is connected with just four wires (B+, B-, field, tack) but there is a small metal box on the side that has wires going into the alternator cans and to a plug that has never been connected to anything for the 24-years I have owned this boat. Do you know what are those other wires are for?