2012 8.1 alternator.

[2ridgebacks]

I believe I have an alternator with bad bearings. I am fairly sure an automotive alternator will work, but can anyone say for sure? Using a gm truck works for the parts guys as a required vehicle to look up parts, but what about the year? Any help is appreciated.

[Big Block Power]

I know you should use a marine starter. They are shielded differently. Not sure on the alternator? I myself would get a marine one or bring it to a shop that rebuilds them and have them replace the bearings.
What did you end up buying?

[Bfun220]

For what it's worth, I agree with BB.
I would get your alternator rebuilt if you can.

[2ridgebacks]

A25. I'm kind of on the clock. That is why I wanted to buy a reman auto alternator. Curious to any differences.

[Bfun220]

I did a quick search and found this.

the marine unit and the Autozone units will both do the same job of generating electricity, the critical difference is the ignition protection. Marine electrical components are shielded or screened so that they cannot ignite fuel vapors.

[Big Block Power]

Yep that's what I heard as well. I knew the starter was don't think I would chance it. Congrats and get pictures of her up.

[2ridgebacks]

I was thinking along the same lines.

It was a brokerage boat, and wasn't cleaned prior to sale. I'll post pics after a good shine.

A25 w/8.1 catalyst engine. 400hp. So far the family hasn't quit smiling and that what it's all about for me.

[Big Block Power]

Good deal.I agree.

[notstock4long]

Looks like it has been said, but DO NOT use an automotive alternator! That's probably one of the main causes behind boats blowing up. This is one component that is worth the price you pay just for the marine version.

[Boensch]

I had to get a marine alt for mine . Stick with a marine alt

[smokymance]

Where did u guys get your alternator from. My 2003 Volvo 8.1 alternator seems to be on its last breath. I can’t get it to show more than 11.8V to 11.9V on the perfrctpass gauge. Took it home and put the volt meter on it and it still can’t get over 11.9. Time to get a new replacement. Where is a good place to get a new alternator. Sucks it’s happening right before our trip upnorth.

[Big Block Power]

Where did u guys get your alternator from. My 2003 Volvo 8.1 alternator seems to be on its last breath. I can’t get it to show more than 11.8V to 11.9V on the perfrctpass gauge. Took it home and put the volt meter on it and it still can’t get over 11.9. Time to get a new replacement. Where is a good place to get a new alternator. Sucks it’s happening right before our trip upnorth.

Double check the single lead wire on the back of it. They come loose.
You would have to search marine grade alt to see who has one. You might be able to hey one shipped Amazon prime or local parts store may have one.

[2ridgebacks]

I’d like to tell you, but it turned out not to be the alternator.

[smokymance]

I think it is not the alternator as well. I put the muffs on it and started it up w the volt meter again. She is pushing about 13-14 amps. I have a huge AGM battery in there, Intimidator 8A8D instead of two individual ones. This thing is a monster, weighs about 160lb. I’m thinking the alternator just can’t charge it fast enough or it is maybe going bad. Battery is from 2014 and it didn’t get used much in the last year and half

[Driller]

But shouldn’t the gauge read from the alternator? Asking for a friend.