alternator

[traveling man]

I have a '94 mercruiser 3.0 4 cyl. I took my boat out for the first time this year and the volt meter read 11.8 -12 volts. I charged it up over night. Usually in the past it has read 13 volts. I think my alternator is shot. Once i have it checked, can i get a new alternator from NAPA for this motor or do i have to go to a marina?
Thank You
Chris

 

[Coors]

Re: alternator

Napa; should read 13.5 +

 

[Boatist]

Re: alternator

You can get one form Napa but make sure it is a marine alternator. Other option would be to repair the one you have. It can be simple and cheap to repair. Make sure the belt not slipping and none of the plugs fell off. Follow your manual and check the slip rings, diode block, voltage regulator and on some model a diode triode can make it charge but very slow.

 

[Robj]

Re: alternator

You can go to a alternator shop and get it rebuilt. That is probably your cheapest option. Whatever you do, just make sure it is a marine alternator that you install.

Have a great day,

Rob.

 

[traveling man]

Re: alternator

Thank you for your replies. I will have it tested and install a rebuilt marine or new marine alternator if that is the problem.
Chris

 

[traveling man]

Re: alternator

I took the old alternator out and it came out in 2 pieces. I took it to NAPA and they could not find the one i needed. Mine is a 817119-2( which is a 4 wire) All they could find in their MERC book was a 817119-A1 and a 817119-A4. Can anyone tell me which alternator i need. I am going crazy not being on the water, please help!!!

 

[Don S]

Re: alternator

817119-A4 Is what Merc calls for now. It is a 4 wire alternator.
Merc used 2 different kinds of alternators, and the above number replaces both. What type did you have? Here is the 2 merc used.

 

[traveling man]

Re: alternator

Don, My alternator is the top one 72078. So i need a 817119-A4?
Chris