Don't bother
My h34, 1984 has a 25 amp alternator on the 3 cyl. yanmar 3GM30. That is probably no more than you have now (or at least not enough increased ouput to bother). Per the Seloc manual on Yanmar, different alternators are available from Yanmar, but you can't just assume that the bigger engine has a bigger alternator. My solution was to purchase a Balmar, 100 amp, 2 charging circuit alternator with an external regulator. It is almost a "bolt on" job, and doesn't take a lot of expertise to install. It actually give me 115 amps., and it can be connected to two seperate battery banks simultaneously. It will charge one, both, or the other bank, at up to 100 amps., depending on need, not requiring isolation diodes. The bad news is the setup runs about $600. If you have any questions, feel free to email me directly: photoron@earthink.net (PS: I'lll give you a great price on my old alternator!)
