Offshoreonly.com - Battery issue?

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Quote:

Originally Posted by Blueabyss (Post 4555995)

First I would not call 12.7 fully charged. should be 13.2 at a minimum. I would check your charger and or alternators . Second make sure you have a ground wire coming off each battery going to the block. Not just a jumper black wire going from one neg terminal to the other neg terminal then to the block.

Chris

12.6 v is fully charged. Check for voltage drop between battery and starter.

Quote:

Originally Posted by F-2 Speedy (Post 4556265)

WHAT ?? never mind

Just commenting on what endeavor1 had "originally" with ground from engine to engine and back to one battery. Personally I've always had each engine ground to battery with a strap between engines as well as battery to battery. Grounds can be troublesome leading to failures on who knows what.

Agree ^^^^ I couldn't figure out the wording

I hate grounds!!! They always seem to cause me the most issues and are tough to track down. Over the years I'm getting better though. Ohm meters are my friend along with a wire wheel to clean up contact areas:ernaehrung004:

kinda like an older rusty Michigan pick up truck with a snow plow issue. I just end up running grounds everywhere and problem solved. Lol.

Quote:

Originally Posted by AllDodge (Post 4555851)

Ya know you might just need new starters, but still think this is a wiring or bat thing.

I just changed out this year from original Merc to permanent magnet starter and boy does it spin over fast now

Can you please explain the permanent magnet starters and whether or not they are plug and play? My SB engine spins slower than port and I plan on replacing the starter as a result when doing mani's/risers. . . Maybe a PM if you are kinda enough and don't want to hijack the thread.

Quote:

Originally Posted by Blueabyss (Post 4555995)

I have 1 G27 Deka Deep and per Deka the full charge voltage is 12.5. Just bought a Duracell G27 Combo., full charged volts is 12.7. You have to check with the manufacturers data sheet for your batteries, they're not all the same.

Quote:

Originally Posted by endeavor1 (Post 4556310)

I love them, much more cost efficient than replacing expensive components!

Read up on how to charge agm batteries,,,,,there different than lead acid

Quote:

Originally Posted by endeavor1 (Post 4556260)

Are these 500s still turning belt driven air cleaners? When I had M3s on my 500s if the battery was in any way down or bad connection it did the same. To be honest, I bought a spool of OO gauge wire this winter and built new cables. My BT was originally setup with a shared ground between the engines then back to 1 battery. Now both motors go to an individual battery. It made a difference.

Yes these are still "belt driven air cleaners." Think I found my problem - had a ground that wasnt connected (my bad when I put in the new charger). I also rewired the battery switches - not quite sure what BT had in mind when they wired them . . .. thanks for all the help everyone!