Page 2 of 2

Re: 2012 8.1 alternator.

Posted: Sun Jul 01, 2018 8:44 pm
by smokymance
Driller wrote: Sun Jul 01, 2018 8:38 pm But shouldn’t the gauge read from the alternator? Asking for a friend.
I know right. So is it the alternator then and I’m the dummy that can’t figure this out ???

Re: 2012 8.1 alternator.

Posted: Sun Jul 01, 2018 10:30 pm
by Bfun220
A big bad battery can draw down your system voltage. Try a new battery. Sounds like it's time to replace it anyway.

Re: 2012 8.1 alternator.

Posted: Mon Jul 02, 2018 8:14 am
by Ytmsn
So what did it turn out to be 2ridge?

My dash meter started showing low voltage this weekend. Even running at 30 mph it was left of center. Then last night we idled out into the cove and it did fine. About to go fire it up this morning and check it again. It's that inconsistentcy that has me worried.

Re: 2012 8.1 alternator.

Posted: Mon Jul 02, 2018 8:40 am
by smokymance
Ytmsn wrote: Mon Jul 02, 2018 8:14 am So what did it turn out to be 2ridge?

My dash meter started showing low voltage this weekend. Even running at 30 mph it was left of center. Then last night we idled out into the cove and it did fine. About to go fire it up this morning and check it again. It's that inconsistentcy that has me worried.
I’m assuming you have the same gauge as me. I recall seeing it in the middle before, but last time I took mine out it was to the left. Sounds like we are on the same boat (lol see what I did there ) and maybe they are working as they are supposed to be ???? I haven’t had this boat long enough to know it’s ins and outs.

Re: 2012 8.1 alternator.

Posted: Mon Jul 02, 2018 8:48 am
by Ytmsn
It should be to the right if its charging and working correctly.
I'm going to check mine with a voltmeter first, as well as both batteries. My batteries are less than a month old but one could be bad I suppose.

Re: 2012 8.1 alternator.

Posted: Mon Jul 02, 2018 9:55 am
by smokymance
Could an alternator provide good volts but bad amps? Mine was reading 13.5+ volts when i measured it but i have no way to check amps.

I did another test : disconnected the positive off the battery when the boat is running. I know this might not be a safe idea but the boat kept running. To me that means the alternator is pumping enough to at least keep the boat running and the boat is not using the battery to keep itself going.

Re: 2012 8.1 alternator.

Posted: Mon Jul 02, 2018 6:44 pm
by thunder550
smokymance wrote: Mon Jul 02, 2018 9:55 am Could an alternator provide good volts but bad amps? Mine was reading 13.5+ volts when i measured it but i have no way to check amps.

I did another test : disconnected the positive off the battery when the boat is running. I know this might not be a safe idea but the boat kept running. To me that means the alternator is pumping enough to at least keep the boat running and the boat is not using the battery to keep itself going.
Probably not a good idea to try that again, it can cause damage.

http://www.troubleshooters.com/dont_dis ... attery.htm

Re: 2012 8.1 alternator.

Posted: Mon Jul 02, 2018 7:23 pm
by 2ridgebacks
Ashamed to admit it, but the belt had gotten hard from sitting and had squeaky spots.