marine battery help

[Brad Byrd]

I bought a new boat back in January--- 07 Bayliner 18' bowrider i/o ---- the battery seems to drain down really quickly even though once a week I fire it up and let it run for 15-20 mins. It has never left me stranded on the water-- but usually the night before going out, I will check it out- run it for a while--- but I have had to jump start it 3 times.... any suggestions? should I unhook the cables when it is not in use??? any help would be appreciated..... thanks, Brad

 

[Mark G]

A battery disconnect switch is always a good idea on a boat. It should be wired to shut off everything on the boat except the bilge pump(s). The bilge pump should be on a separate fused circuit that is hot all of the time. The next thing to check is why the battery discharges so quickly. Is it a battery problem or parasitic drain? Radios on boats are infamous for excessive battery drain. You an expect a small amount of parasitic drain from electronics, maybe .02A (20 milliAmps) to as much as 50 mA. Check the link below it may help you to find what is draining the battery. (assuming the battery is not the culprit)

 

[Kevin Palmer]

Yep, you have some sort of a drain...



Get the switch and eliminate the issue...

 

[Rich Stern]

The switch is a great idea, but it would also be a good idea to figure out what is draining the power. Does the dashboard have a depth finder? Does it shut off with the ignition switch set to off? That's a very common source of battery drain. Check for other accessories that might be on. Storage area or courtesy lights that are hard to see by daylight, etc.

 

[Dingo]

 

[KentheREALone Z]

Put a master circuit breaker in.

Radios, as said, are often the culprit.

You can also turn all off, and disconnect the battery. Touch the positive terminal, if it arcs, you've got a drain somewhere.

 

[KentheREALone Z]

Put a master circuit breaker in.

Radios, as said, are often the culprit.

You can also turn all off, and disconnect the battery. Touch the positive terminal, if it arcs, you've got a drain somewhere.

 

[Jim P]

starting it up weekly and letting it idle 15 min will probably NOT recharge the battery enough to replace the stored energy used to start it in the first place, you could also have a bad cell in the battery

 

[Wes Davis]

My suggestion would also be a battery automatic charger/maintainer. I was having problems as well but now my boat is left 100% plugged in at the dock and never a problem since. Two batteries one wet cell, one gel cell and a 1-2-All battery switch. I have many battery drains such as a stupid radio with random display/demo mode everytime you turn it off and a bilge pump that cycles every five minutes to search for water.