Alternator help

[granpafish]

Well, we bought the boat, a 99 Parker with a Merc cruiser 5.0 bravo 3. Low hours, clean, and generally in nice shape. We replaced the batteries and it looks like the alternator is not working at this point. #1 What should I look at first? #2 if I can't find the problem, is it reasonable for me to remove it for inspection and testing by a pro? What cautions do you have for a less than mechanically inclined, aging, pursuer of fin fish? Thanks Granpa

 

[rodbolt]

Re: Alternator help

hello<br /> with the key on engine off test for 12 volts at the purple wire at the altenator, test the small red wire at the alt for 12 volts and test the oroange 10 ga wire at the output for battery voltage. if all show battery voltage then remove the altenator and send it out for repairs. good luck and keep posting

 

[loadnet]

Re: Alternator help

..you may get lucky and try putting a volt tester on the battery while the engine is running.<br /><br />See if the reading you get is much higher than what your dash guage is showing and your batteries are not going dead...you may just have a bad guage in the dash.<br /><br />The only reason I'm mentioning this quicky test is because you failed to mention - how - you determined your alternater was bad?<br /><br />The more info you supply - the easier it is for everyone to jump in and help you.

 

[granpafish]

Re: Alternator help

Yeh, you're right, should have posted that info. After replacing the batteries, we went out just to run a little bit and get a feel for the whole boat. While running, we noticed that the volt meter was just sitting at about 11.8 or 11.9. It stayed there whether the engine was running or not. During the trip, if the meter moved at all it was down a .1 or so. We had no test equipment with us at the time and have not had a chance to get back to the boat yet. I realize that there could just be wire that has vibrated loose and am hoping for that, but am looking for as many things to check as possible. Even if it is a easy fix, I always learn from the responses I see here. Thanks for your help. Granpa