CAT 3126 Battery recommendations?

[david_h]

My 400 sedan bridge has twin CAT 3126 engines. This spring the existing batteries would not turn the engines over unless the 'emergency' switch was depressed. The existing batteries were group 31 deep cycles, 2 in parallel per engine. Not sure of the battery age in this new to us boat.

My previous boat had 2 6volt batteries in series to great effect. Long lasting and good capacity. So after talking with the battery shop that is what I went with. 2 6volt in series batteries per engine. 235 aH per battery. However I find that I still need to use the 'emergency' switch for every start with these new batteries.

Questions:
1. What battery type and size is recommended for these engines and application given the additional 'house' role of the battery pairs?
2. Where is the emergency solenoid located? Does it break down often and is there a concern with using it for every start?
3. I noticed that the westerbeke generator starting battery only has a single black and red going to it. Does it get recharged by the genset while it is running?

Many thanks for a lot of questions.

Dave

 

[k9medic]

I have two group 27 wet cell deep cycle batteries from NAPA that do just fine. They are only around $85 per battery. I have only had to use the emergency switch once and that was when one battery level was low on water and melted the plates.

The gen set has its own battery that is only charged when the gen set is running.

 

[HUMPH]

It depends how you use your boat. If you usually run your generator, group 31's are fine. If you anchor out and want quiet, I would install larger. I have Trojan J185H X 2 for my house bank.

 

[david_h]

Ken do you mean that you have a house bank and a starting bank? What batteries do you use for starting?

Dave

 

[The Bill Collector]

I have two group 27 wet cell deep cycle batteries per engine from Costco and they are great...

 

[PMC]

My 400 sedan bridge has twin CAT 3126 engines. This spring the existing batteries would not turn the engines over unless the 'emergency' switch was depressed. The existing batteries were group 31 deep cycles, 2 in parallel per engine. Not sure of the battery age in this new to us boat.

My previous boat had 2 6volt batteries in series to great effect. Long lasting and good capacity. So after talking with the battery shop that is what I went with. 2 6volt in series batteries per engine. 235 aH per battery. However I find that I still need to use the 'emergency' switch for every start with these new batteries.

Questions:
1. What battery type and size is recommended for these engines and application given the additional 'house' role of the battery pairs?
2. Where is the emergency solenoid located? Does it break down often and is there a concern with using it for every start?
3. I noticed that the westerbeke generator starting battery only has a single black and red going to it. Does it get recharged by the genset while it is running?

Many thanks for a lot of questions.

Dave

what are the CCA for that battery combination? Not enough amps to the starter. Either a bad connection or the batteries cannot supply the large burst needed during starting. I'm not an expert on this, but I thought a lot of folks opt to use 6v bateries to build up a large amp hour house configuration. On the 400 you have both charging and house on the same battery cluster.

Emergency selenoid is mounted port side next to the battery charger / converter. I would opt to get the starting issue resolved before resorting to normaly using the crossover.

Assuming you have the 8btd, it does have an alternator to charge.

 

[david_h]

In the end I was able to exchange the 6v batteries for 2 pair of group31 combo deep/starting batteries. Each group31 battery has 850CCA so in parallel I have about 1700CCA per engine. And the house capacity is not too bad either.

thanks to everyone for their comments.

Dave