alternator charging question

[mind]

i just purchased a 1994 wellcraft elicpse 232 with a mercruiser 350.<br />the voltage fluctuates between 10.5 and 12 volts while running. i'm used to a car where the voltage is 13-14 volts while running. i took the alternator up to a couple of part stores and they didn't know how to hook it up to test it.<br /><br />what voltage does the alternator normally put out?<br /><br />thanks

 

[northvanwatertaxi]

Re: alternator charging question

mine puts out 13.4 volts, its a 302 ford, you should have a marine one in my opinion

 

[calwldlif]

Re: alternator charging question

Alt can put out upwards of 20 volts,
regulators keep the voltage between
12.8 13.6 average.
New style alt have internal regulators
and go bad. a rebuild shop
can fix whatever trouble the alt is
having, at really good prices

 

[jlinder]

Re: alternator charging question

The voltage should be in the 13.6 or so range, maybe a little higher, and pretty constant. Your voltage indicates you have a bad alternator.

The alternator can be checked easily - electrically they are pretty much all alike to the outside world. Most have internaal voltage regulators. You have the output terminal (big bolt), the ground (case), and the sense wire. Maybe someone here can give you a cross to an electrically equivelent automotive alternator.

The big difference is that marine alternators NEED to be sealed to prevent sparks from igniting any possible gas fumes.

If you need to replace it, and it sounds like you do, make sure it is marine rated.