Dead starter battery

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ralphgamble

Member
Joined
Sep 28, 2017
Messages
5
Location
united States
Have a 36 foot trawler. Have a starter battery and a series of house batteries. I forgot to switch to house batteries with shore power and Left my engine room light on. Now my starter battery is dead. Can I get a jump using portable power pack?
It is a brand new battery and am worried I hurt it by draining it.
 
Yes, but how? I will switch to "both" on my panel to see if shore power will charge it. In our marina, I wonder if they provide this service to jump start.
 
yes it can be jump started remember to have adequate ventilation around the battery and motor when you jump it sparks can do all sorts of nasty things on boats
 
You can always remove the battery and charge it!


Cheers.


H.
 
Ralph, do you need to go somewhere quickly?

Does your shorepower charger routinely charge that battery too?

If you're not heading out soon, and if your charger is set up to routinely charge that battery anyway...

I'd guess just turning on your charger would bring it back to as good as it will get. Don't see any real need to jump it, unless you're in a hurry to zoom our somewhere...

-Chris
 
Agreed on letting the shore power just charge it.

One can jump it, but the caution comments here are appropriate. Also, is there an option to start using the house batteries?
 
Also agree with: 1 letting the shore power charge it, presuming your battery charger will handle it, is wired to charge the various battery banks; 2 charging the battery separately either with the battery charger aboard or a separate battery charger or ashore; 3 jumping the engine using a small, portable power pack; 4 charging the batteries with your genset (same as shore power, if it will start with the batteries you've got); 5 arranging your collection of battery switches so that you can start with any of the batteries you have aboard.

All these alternatives have their own caveats. Charge rate, float rate, different types of batteries. Safety issues including off gassing, sparking, boiling, wire size, other electronic goodies.

I have to wonder about using the house breaker panel battery switch to charge a dead battery. Speed and wire capacity, let alone discharging the good bank to attempt charging the dead...

But for the short term, a jump start and a charge, any of the above will be fine. And the easiest, quickest for you is best.

And for the long term, wiring, switching, fusing, charging, etc., needs to be worked out so that silly errors and ageing batteries still allow you alternatives to get going. (Continuing my past summer's adventures, I now cannot charge my house bank with engine power, nor can I start an engine w/o its own battery (or jumping from another bank).)
 
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If in a hurry using cables you could jump start from the house bank. I agree with letting the shore charger do it. It will probably take days but if not in a hurry so what?
 
"It is a brand new battery and am worried I hurt it by draining it."

A start run dead the worst possible way , a small load left on till dead may not respond to most 120V chargers.

They usually need to have some voltage left , in order to charge.

An installed rotary switch should allow a start from the house , and if left connected for a few hours might get the start back to holding a charge.

A dead start that is recharged will be 10-15% less powerful than a new one , but is probably fine for summer use .
 
Our boat only has on/off battery switches. I have not had a chance to add a parallel switch yet, but I will in the near future. I already owned a large jump start pack. I carry it when cruising in case we have a dead start battery. No problem starting with the jumper pack, I have started our diesel pusher motorhome with it. If you have gas engines you must be very careful with fumes and the spark when you connect the battery pack, so I would not do it on a gas powered boat.
 
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