Mainship batteries

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Joined
Oct 13, 2014
Messages
15
Location
Memphis TN
I have a 1980 Mainship ll with 200 HP Perkins Turbo Diesel.

What size batteries should I be using?

When I acquired the boat 4 years ago it had 2) size 27 cat batteries in it, They did not last long. I was told they were not the correct in any case. I replaced them with a pair of 4D's and thought I put the problem to rest.


The guy who installed them forgot to tighten the cables, (they were finger tight). This caused them to get very hot at some point and resulted in failure.


I am in process of replacing them again and would like to put the correct batteries in this time.


Also, my charger has quit, what charger do you recommend?


T
 
What was the failure? Did the terminals melt? If the suspected cause of failure was loose terminals, all the heat generated from the loose terminals would have literally melted them due to the high resistance at that point. Dual 4D should be plenty to start just about any Marine Diesel.

What space is provided for the batteries? How many cranking amps does your starter/engine required? More details about what the failure symptoms were?
 
Well, first you need to understand house use ie lights, fridge, etc, vs starting. These two services take two different types of batteries and also need to be isolated so you don't run down your starting battery after a couple of nights on the hook. Most boats are wired with a 1,2,all, off switch that does this if you operate the switch correctly.

Your 4Ds were unlikely to have been true deep cycle batteries and that is one reason that they didn't last.

A good group 31 starting battery is what you need for starting your Perkins. It should have about 900+ CCA rating. Two pairs of 6V golf cart batteries wired in series to give 12V is the cheapest true deep cycle battery for house use.

You can use either standard flooded cell batteries or AGMs, but the latter cost at least double.

Check out Defender for chargers but I would install a 40A Promariner. 40A is about as big as you want for two GC batteries and it will recharge quickly at the dock or even with a 2,000 watt portable Honda generator.

David
 
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36 foot Albin, Single F.L 120 hp. House batteries, 3 group 27 deep cycle. Starting battery is slightly smaller, just one starting battery,isolated if I need it to be. I have a starting battery on my windless and one on the 3 cyl. Yanmar Gennie. The windlass battery was still pretty good but last year I replaced all 6 batteries. I think a problem is trying to mix new and older batteries.This way I am good to go. If something unforeseen happens and kills a battery or two I have spares and always carry jumper cables and a jump pack.
 
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