seeking functional 35 amp Motorola alternator
 

Hello All -

Boat is in the water. Alternator failed. No headspace to get to the bracket and headbolts nor any enthusiasm to do so to rework bracket to put a new high output alternator in at the moment. Can't get to the headbolts easily. If I break one or fail to retorque properly then I'm in bigger trouble.

So - looking for a functional alternator to get me through the season when I can better assess the options and the costs.

Any help or leads to find one very much appreciated. Thanks

George Barringer
Enterprise
1978 Erickson 32 mkII

I am not sure of the relationship between headbolts and alternators. I have used several types of alternators and never had to remove the alternator braket. They all use the same mount.
The only thing you need to change for some alternators is the mounting arm from a shorter to a longer one and that is trivially easy to do and involves no head bolts. We use single foot 2" alternators, so any such alternator will fit the bracket on the head.

Also note that you can have your existing alternator repaired.


EDIT - If you move away from Motorola alternators to the numerous 10si types or a Balmar, besides for a belt this is the only part you HAVE to get:
https://moyermarine.com/product/alte...l-ovel_03_222/

I know of what George speaks. When I went to a higher output Delco alternator I had to relieve parts of the alternator/lifting eye bracket with a grinder to get it to fit.

George, where are you located?

I didn't do that for a 10si, but I did get the longer arm to allow it to move farther away from the block.
EDIT - What is a 10si? GM long ago started making the 10si series of alternators. They have come in everything from about 40 to over 100 amps with various voltages and various regulators. They have been copied by myriad manufacturers over the years and are available at every price point in marinized and auto versions from 1,000 places.
They fit an A4 with the longer arm and/or some grinding on the bracket. The high output alternators Moyer sells are 10si variants. I got a 90 amp 10si for about $50 once. On the good side it was cheap, and on the bad side it was cheap. I got about 1 year out of it.

Motorola Alternator
 

Thanks all -

I am in Massachusetts.

I am searching for an alternator repair shop willing to take it on but I did also learn that the Moyer catalog has a "one for one" replacement. So, I may go that route as enthusiasm for rebuilding a 40 year old unit is limited in these parts.

This all started when I took the alternator out in the winter in preparation to add an adjustable tensioner from Moyer. Don't fix it if it ain't broke.

Thanks all

George

George, depending on which route you decide, I have a 35 amp Motorola alternator. I have no idea if it works now, but it did when it was unbolted from its host years ago. It was given to me as a spare by a guy that went diesel. I would have taken to my local shop for a rebuild if/when mine fails but it is still ticking.
So, we can talk..I see no reason to keep this one, and would be happy to work out a deal we are both satisfied with.

35 amp alternator "foam"
 

I am in kind of the same "boat". I took off my alternator to inspect it and clean it. I wound up (no pun intended) somehow disturbing some foam under the bracket that disintegrated. Does anyone know what this foam was and if I can replace it?

I can't seem to find a repair shop in MA or ME yet.

I was looking at the 55 amp and 120 but now sure if I should just stick with 55 amp.

- John
1977 Pearson 28-1

PS: Found Mr. Moyer's write-up on selecting an alternator...

As a practical matter, in the stock location NO alternator is going much over 50 amps. FYI