Crank Battery for Cummins 6BTA 330

[5teve]

Hi

Yes another question...

Currently the boat has 2 batteries per starter bank - however I would like to repurpose these to add to the house bank.

Is it really necessary to have 2x starter batteries per engine? or would i be able to use just one correctly rated battery per engine - and in which case is 1100cca the correct rating for the engine?

Thanks

Steve

 

[burgundyben]

Check the manual. It's in there.

 

[5teve]

It says 1100cca which can be gotten in sub N200 size..

I guess I'm just seeing who else is running a single battery per motor.. i'd prefer not to be using 2 and dont want to go N200 size (or 8d etc) i'm thinking cheap lead acid suited to crank only.

I'm also trying to work out what the Previous owners were thinking when they wired the batteries up! as each motor has 2000cca of crank power available - but the port is slow to start (new batteries also) and I think its down to the mammoth amounts of wiring from batteries to switches and back to motors. Each battery is paralleled to its counterpart though a dual battery switch with the switch set to both - probably around 6-7m of wiring at least to the port engine.. - still trying to unravel all the wiring.

I also have 3 alternators on 2 engines.. 1 alternator per bank.. I'm thinking ACR's as I have on my small single engine boat to make things simple (and safe as the aux alternator bracket is a bit sus.. and unguarded)

Steve

 

[burgundyben]

How long and how thick are the cables.?

 

[5teve]

as mentioned to port engine probably has 6-7m of cable from the battery to starter - but its decent battery cable - I havent measured it but i'd be thinking its at least 0B&S (50mm2)

Starboard side probably has 3-4m of cable

If I rearrange the batteries (other post) into one large house bank, 1 genset battery and 1x start battery per motor - I'll be planning on reducing lengths to a few meters per engine and moving the battery switches closer to the batteries.

Steve

 

[Keith-i]

In my experience ratifying unnecessary wiring and switches makes a huge difference to starting performance. Decent cable, crimps and connections are the way to go.

 

[burgundyben]

as mentioned to port engine probably has 6-7m of cable from the battery to starter - but its decent battery cable - I havent measured it but i'd be thinking its at least 0B&S (50mm2)

Starboard side probably has 3-4m of cables

If I rearrange the batteries (other post) into one large house bank, 1 genset battery and 1x start battery per motor - I'll be planning on reducing lengths to a few meters per engine and moving the battery switches closer to the batteries.

Steve

off the top of my head that seems long and skinny.

I think you have an inline pump? Is there energise to run? In which case you don't want voltage drop. Short fat cables = happy.

 

[superheat6k]

The 6BTA5.9s on my boat have one 130AH battery each, one of which is the domestic. I recently added an extra 80AH to the domestic to provide reserve capacity.

The best Manual I have found says 800 CCA for light accessories. Heavy accessories are hydraulic pumps and torque converter.

Mine spin over freely and start within a few turns even in cold weather.

Manual here if you are interested

https://www.dropbox.com/s/qkxah8h7l2dshgj/Cummins B Series Engine Manual.pdf?dl=0