Spare alternator

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SeaBreeze
Posts: 91
Joined: Wed Aug 05, 2015 8:15 pm

Spare alternator

Post by SeaBreeze »

I have a 2003 Catalina 350 with the M35B engine. The alternator is the Mando 51 amp that came standard. No part number found. The owners manual mentions a possibe 71 amp alternate. The Westerbeake wiring diagram #200360 for Catalina shows 3 alternator options - 51 amp Mando, 51 amp Motorola (Prestolite) and 72 amp Prestolite. Wiring for each is slightly different. Mounting interchangeablity is not defined.

I would like to have a back up alternator just in case the existing one dies while we are cruising. Is there someone on the forum that can answer one or both of my questions below regarding a choice of back up alternator.
1. What would be the brand and part number for an exact replacement (wiring, mounting)?
2. Is there a higher amperage output model (72 amp?) that would be an exact replacement. If so, what brand and part number?

I undrstand there are high output alternators with internal or xternal smart regulators available but I do not want to go to that expense. Alternator output isn’t a big concern to me. Simple, no modification required is what I’m most interestd in. Think - changing out a dead alternator while floating around in the Gulf of Mexico.
Best regards
Rick
Sea Breeze - currently in Tampa Bay
Rick Parish
Sea Breeze
JohnNorton
Posts: 59
Joined: Thu Oct 13, 2011 12:27 pm

Re: Spare alternator

Post by JohnNorton »

I replaced Mando 51 amp factory alternator with same (Mando Part No. 18-5966, 55 amp rating) about a year ago. 2004 boat had seemingly low alt output. A big improvement in charging batteries with the new alternator; also as a direct replacement pretty much a "plug and go". kept old one as a spare as it works, just not as high of output.
SeaBreeze
Posts: 91
Joined: Wed Aug 05, 2015 8:15 pm

Re: Spare alternator

Post by SeaBreeze »

Thank you John. Sounds like exactly what I’m looking for. Same mounting, same wiring, same pulley. I would also install the new one and keep the original as a spare. Amazon has it for $113 and free shipping.
Rick
Rick Parish
Sea Breeze
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