What is the Standard Mac Battery Type?

[richandlori]

I am trying to figure out what type of battery came standard with my Mac 2004 26M? I am starting to charge the battery for the first time and can't find out what type of battery came standard with the boat? Deep cycle, standard, AGM, or Gel-type. It is irritating that I can't find what I would consider necessary information about the battery.

HELP

[Tom Spohn]

Rich,
The type of battery depends a lot on what the dealer installed. Why not just remove the battery cover beneath the ladder and see what is there? Also take a look under the aft bunk all the way astern as some dealers place batteries there to be closer to the engine. On mine for example, I have a flooded 70amp 12 volt for the engine and two golf cart batteries in the battery compartment for the house (total 245 amp/hr). All are connected through a West Marine Combiner and a permanently mounted charger.

[Kevin]

It seems to me that the battery may not come from the factory and be whatever the dealer sees fit to install.

I opted for two batteries and ended up with generics. Both flooded. One is a "standard" starting type battery and the other is a deep cycle. They are connected by the good old 1, 2, both, off type switch.

Since I can't leave things be, I added an AGM battery connected in parallel with the deep cycle.

I have that oh so nifty Xantrex link 10 battery monitors. I'm doing some tests to get a handle on capacity. I ran one interior light for 12 hours and that used 39.5 amps. Battery was down to 12.45 volts. By my chart that says I used about 10% of the battery capacity.

Now I have 3 solar cells connected in the driveway. They add about 1.4 amps per hour when I checked them for a total of 10 amps a day.

What fun!

[Sloop John B]

If it's like the x batteries, it's the low bid auto battery. Works good. Put your charger on low maintenance automatic and sit in the boat and watch it so it doesn't dissolve the boat like Joe 'Time Warp's' did.

[dclark]

I don't think there is such a thing as a standard Mac battery. I'd imagine most dealers would install a group 24 starting/deep cycle combo if you only have one. It's probably a better idea to have one battery dedicated to your motor and a second for the house. I currently have a group 24 starting battery and a larger group 31 deep cycle house battery. I bought the boat new and the dealer had installed two group 24 starting/deep cycle batteries. What size and type you go with (gel cell, AGM, or whatever) is entirely up to you and how much you want to spend.

[mgg4]

Since I can't leave things be, I added an AGM battery connected in parallel with the deep cycle.

Be careful. You should not mix battery types in the same bank. They have different charge characteristics, and you can damage one or both batteries, and/or cause problems in your system.

--Mark

[Paul S]

Since I can't leave things be, I added an AGM battery connected in parallel with the deep cycle.

Be careful. You should not mix battery types in the same bank. They have different charge characteristics, and you can damage one or both batteries, and/or cause problems in your system.

--Mark

The battery in our M seemed like a generic. Just said 'Deep Cycle Battery' kinda like if you buy generic beer with "BEER" on the label

I am sure it works OK. Just the same...I changed to 2 group 27 Rolls wet cell batteries (house/starting) with 3 switches and a built in combiner.


Paul