The Official Dual Battery Thread

[waterlogged882]

My first thought was to get them made at one of the companies you listed, just wanted to make sure that was the best bet. For the price of a crimper, I think I'll just pay for made up wires.

I like Genuinedealz but they seem to have been out of stock for a lot of items for a good while. He is a one-person operation out of his basement but always has done me a good job in a timely manner. I feel certain that Greg's place (upon the recommendation here) is just fine. Best on the install.

[dpb185]

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Did you use standard or heavy walled lugs ?

[waterlogged882]

Did you use standard or heavy walled lugs ?

Standard lugs and (importantly) tinned wire.

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[dpb185]

Another termination question. The power wire coming from the engine to my single battery has a battery post terminal connection at the end. What's the best/easiest way to change this to a lug terminal ? Wire is circles on the diagram below:

[waterlogged882]

Another termination question. The power wire coming from the engine to my single battery has a battery post terminal connection at the end. What's the best/easiest way to change this to a lug terminal ?

One of two:
1) Cut the terminal off and crimp back a new ring connector lug. A pack of lugs are relatively inexpensive from Scamazon. A manual hand crimper will work...the crimps are just not real pretty, but that is not a show-stopper. I have seen people use a chisel and hammer to make (3-sided) hard crimps on larger connectors. The objective is to get a good connection at that point.

2) Order a new wires (both hot and ground) with ring connector lugs attached. I do not suggest to get new cables as a way to throw in the towel but to be proactive in preventative maintenance. If you do, get tinned wire cables.

That's about all I can suggest. I thought about something to use as an adapter but that wouldn't work.

If you get to a point that you need a larger hole in (any) a ring connector use a Step bit (Harbor Freight) in a drill and it will enlarge the hole very nicely. Do not use any other type spiral bit...it will just twist and ruin the connector.

Your diagram showes 1/0 AWG cable. That is a big cable. I personally use 2 AWG all around with no problems but that is your call.

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[MLA]

Does the boat have a 400A alternator?

[dpb185]

Does the boat have a 400A alternator?

I stole that diagram from a previous post. I plan on using 2 AWG.

[MLA]

Still, 2 ga would handle 300'ish amps in a short run. WAY overkill for alternator load. As to not using 1/0 or using 2ga in other parts of the schematic, id calculate my own loads and see what you come up with.

[dpb185]

One of two:
1) Cut the terminal off and crimp back a new ring connector lug. A pack of lugs are relatively inexpensive from Scamazon. A manual hand crimper will work...the crimps are just not real pretty, but that is not a show-stopper. I have seen people use a chisel and hammer to make (3-sided) hard crimps on larger connectors. The objective is to get a good connection at that point.

2) Order a new wires (both hot and ground) with ring connector lugs attached. I do not suggest to get new cables as a way to throw in the towel but to be proactive in preventative maintenance. If you do, get tinned wire cables.

That's about all I can suggest. I thought about something to use as an adapter but that wouldn't work.

If you get to a point that you need a larger hole in (any) a ring connector use a Step bit (Harbor Freight) in a drill and it will enlarge the hole very nicely. Do not use any other type spiral bit...it will just twist and ruin the connector.

Your diagram showes 1/0 AWG cable. That is a big cable. I personally use 2 AWG all around with no problems but that is your call.

.

After looking at making crimps on the web, I think #2 is probably the best option . Plus like you said it's probably a good idea to replace these wires anyway, I'm not having problems with them but they are 20 years old. I'll have to check how complex a job this is the next time I'm at the boat storage.

[waterlogged882]

After looking at making crimps on the web, I think #2 is probably the best option . Plus like you said it's probably a good idea to replace these wires anyway, I'm not having problems with them but they are 20 years old. I'll have to check how complex a job this is the next time I'm at the boat storage.

Cable replacement is easy peasy. Hot from starter to battery (maybe lift a center floor section out for access) and the ground from the battery to a bolt on the block. Connect the battery ends last. Done deal.

These old cables can corrode under the sheathing (site unseen) and create resistance, ultimately to the point of failure. Always good to have a new baseline for reference. Good call.

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[dpb185]

Cable replacement is easy peasy. Hot from starter to battery (maybe lift a center floor section out for access) and the ground from the battery to a bolt on the block. Connect the battery ends last. Done deal.

These old cables can corrode under the sheathing (site unseen) and create resistance, ultimately to the point of failure. Always good to have a new baseline for reference. Good call.

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Nice to know, I have to remove the floor panel to install Perfect Pass and check the bilge pump anyway. Winter project list is piling up ...

[D2Dominator]

New boat, new system.

Quick question: 2010 Star has a 50amp breaker feeding the underdash fuse panel. If this is isolated from the starter battery, and the house bank dies… will the boat still start?

I’m guessing the ECM is mounted to the engine, but I’m not at the boat to verify. Anyone have insight?

thx,
D2