Alternator?

[Grant Brown]

1993 Mercruiser 4.3L Alpha 1 Gen 2
Gauge on dash shows about 10 volts when running. Cranking battery is new, deep cycle is 1 year old, both seem to hold a charge fine. Gauge on dash appears to work.
How do I test the alternator? I have a decent multimeter.
Are they easy to rebuild?

Grant

 

[Don S]

Re: Alternator?

Either check the output directly out of the alternator on the heavy red wire, or test at the battery itself (better idea) to see exactly what is supposed to be going to the battery.
Download the manual, read the rebuilc procedures and see if you think you can handle it.
Personally, I send them out for repair, or replace.

 

[arks]

Re: Alternator?

Your local auto parts store should be able to test it for you (maybe for free). They can be rebuilt but a press is required, not to mention specific knowledge of alternators.
There are plenty of shops that rebuild alternators and starters. Often it's more cost-effective to buy a new one. Guess I'm lucky- there's a guy about 3 miles from me that does this kind of stuff as a part-time business. When I took both my boat alternators to him, it was actually less expensive to buy BRAND NEW, higher amperage alternators than to rebuild my old ones.