View Full Version : Alternator Amp Rating?

01-07-2009, 03:32 PM
I have a Mobius V 2000.
Indmar Assault 5.7L.

About to install a second battery, deep cycle, but need to know the Amperage of my alternator......

Can't read anything on it, as it's probably the original....

50amp standard?

How can i make sure?

Should i play safe and go with an upgrade?

Going to be running an amp and lights from the second battery.

01-11-2009, 09:17 PM
i have a 02 lsv and it has a 70 amp altanator in it

Brian Raymond
01-12-2009, 11:00 PM
The alternater you have is a 70 amp. This is the maximum output at 2000 rpms. Hope this helps, keep us posted. Brian Raymond

Engine Nut
01-14-2009, 12:23 PM
If your boat is a 2000 Model, the alternator should be a 55A Prestolite (Leece Neville) alternator. The easiest way to tell is to look at the alternator. If it is black in color it is a 55A. If it is more gray in color it is a 70A.

02-01-2009, 12:46 AM
How about for a 2008 Outback V?

Engine Nut
02-01-2009, 09:22 PM
How about for a 2008 Outback V?

If the engine is a 325 it has a 70A alternator. All other 2008 models have a 90A alternator.

02-20-2009, 11:32 AM
Been told by Indmar that its a 55amp Prestolite.
I could see the information for the solenoid only.

Have decided not to upgrade just yet......will try running with dual battery setup. have been told it will be plenty adequate.

Got a deep cycle battery just to run the amp, on a solenoid voltage sensing setup, to charge both batteries.

Thanks for the info all!

02-20-2009, 07:52 PM
So I am in the midst of stereo upgrade extravaganza and am starting to wonder if my alternator will keep up. 2001 MoobiusV, Indmar Assault, black alternator so I'm guessing it's the 55A. I'm going to be running a Kicker 750.1 mono to power the sub, Kicker 350.4 for the cabin speakers, and 350.2 to power the tower speakers.

I already have dual batteries with a nice HD secondary battery. I'm a little worried if my alternator will keep up. If I should plan to upgrade alternators or install a capacitor (which I've heard very mixed reviews about)?

Will post some stereo updates to my other original thread - the UPS man came today and it was just a beautiful sight. Like Christmas all over again...