Plug-and-play alternator options?

[bsangs]

My 35-3 has what I assume is the original 55-amp Hitachi alternator connected to its Yanmar 3GM30F. It's model number LR155-20B. Works perfectly well for our two battery needs, and passed my voltage testing without issue. However, before we set sail further away later this summer, I thought it would be prudent to acquire a backup alternator. Unfortunately, from what I gather, Hitachi no longer makes this model, and researching alternators has given me more sea sickness than the boat ever has. I'm just looking for a simple plug-and-play replacement, not some super-charged-serpentine-conversion-required replacement that requires adding more wires or devices that I simply do not need. Models that I have located which appear to be plug-and-play don't get the greatest reviews. Anyone have some experience with this, who wouldn't mind offering suggestions? Thanks.

 

[Christian Williams]

A 100 amp Balmar will work fine with the factory pulleys. They can be detuned, to 90, 80, 70 output if required (if belt slips).

The external "smart" regulator will allow faster charging. I was able to replace the Motorola on the 32-3 without incident, and I am not very good at electronics.

E32-3 - Balmar 100 amp Alternator, Victron Monitor and Cockpit Gauges Splash Guard

.... The external regulator is mounted on the bulkhead, outside the engine compartment. The new Balmar alternator is white, to make you feel special. The issue is power. How much electricity do you need on board, and for how long, before...

ericsonyachts.org

 

[bsangs]

A 100 amp Balmar will work fine with the factory pulleys. They can be detuned, to 90, 80, 70 output if required (if belt slips).

The external "smart" regulator will allow faster charging. I was able to replace the Motorola on the 32-3 without incident, and I am not very good at electronics.

E32-3 - Balmar 100 amp Alternator, Victron Monitor and Cockpit Gauges Splash Guard

.... The external regulator is mounted on the bulkhead, outside the engine compartment. The new Balmar alternator is white, to make you feel special. The issue is power. How much electricity do you need on board, and for how long, before...

ericsonyachts.org

Thanks Christian, some good info there as always, but am just looking for a backup now. Maybe somewhere down the line I'll look into upgrading, but just want to have one on board in case the original dies, so I can quickly replace it.

 

[bigd14]

Maine Sail thinks highly of Leece-Neville alternators. I think I took his advice and tried to get one of these but I’m not sure. I do recall taking my original nasty alternator to an old school alternator shop and having them find what I was looking for or something very close to it. They also tested the starter and found it to be in good shape. It’s externally regulated so I didn’t have to worry about the troubles Maine Sail discussed of overheating. I have had no troubles with it so far, although it’s only lightly used. I’m not sure this will actually be the plug and play option you are looking for but hopefully it might help your quest.

External Regulation Conversion - Leece-Neville 8MR Alternator - Marine How To

A Stock Leece-Neville 8MR Alternator Many boats, both power and sail, come equipped with, or have have used, the 5" small-case Motorola/Prestolite/Leece-Neville style alternator. There are literally thousands of these alternators out there. Even large Caterpillar and Cummins engines have used the

marinehowto.com

 

[Pete the Cat]

I bought a backup alternator for my 3JH4E from a vendor on Ebay (might thought was to test it and then use it as a back up only) I think I paid $60 a couple years ago. It worked and I put it away with my spares. It does not say Hitachi (but neithere did the OEM) on the case, but all the stampings are identical. OK for a backup. I have done this on other parts for other engines. I did buy a oil pressure sensor for a spare that did not work on Amazon and sent it back. My philosophy on spares is that they need to work but need not be expensive.

 

[bsangs]

I went this route Pete, thanks. Looks almost exactly like the current Hitachi. As for testing it, I assume there’s no way to do so without removing the existing alt and hooking the backup up, right?

 

[Pete the Cat]

I went this route Pete, thanks. Looks almost exactly like the current Hitachi. As for testing it, I assume there’s no way to do so without removing the existing alt and hooking the backup up, right?

i suppose you could take it to a shop and they could test it quickly and probably charge you. I actually ran mine for a couple weeks at various states of discharge and then switched it back. On my boat it is actually easier to switch out than it looks. Remember to make sure the main switch is off and nothing is energized back there. My spare has an internal regulator and my other one was modified for external regulation. Some external regulators don't care (like Sterling) but you might need to pay attention to that. Mostly you want to know that it will produce significant amps and that the pulleys are similar. My guess is that these all come out of the same Hitachi factory. Up until a few years ago Leece Neville made nearly all the Bal Mar, Motorola, and most of the others even though they dressed them in all matter of coatings and cases to sell them as special construction.