I have recently purchased a J30, hull #337, and have acquired a Yanmar operation manual for the GM series. This manual covers the 2GM20, but my engine just says 2GM, and is rated for less continuous HP (13) than is listed in the manual (16). The engine is raw water cooled.

I've seen mention in these forums of changing engine zincs and have read enough horror stories about engines destroyed for this reason. Yet the operations manual doesn't say anything about zincs.

So I'm figuring that one of two things may be happening:

1. The 2GM20 in the manual is different from my 2GM, and my 2GM has zincs while the 2GM20 doesn't.

2. None of the 2GM's have zincs, but the 2QM's do, and the people talking about changing zincs on J30s have 2QM's.

So which one is it? Do I have anything more than the prop shaft zincs protecting my engine?

Thanks,

Ryan Pierce
rdpierce@pobox.com

Ryan Pierce, #337