Battery and fuel in same compartment

[webbwebs]

I recently purchased a 1979 Halman Nordic sailboat as a project boat. The boat has a 9.9 Johnson outboard on it that is electric start. Currently, both the battery (for starting the outboard and for lights, etc.) is located in an aft lazerette, next to the fuel tank for the outboard. This is a good place for each of them, as the compartment is sealed from the rest of the boat and fumes from the battery and from the fuel tank can vent to the outside. I'm not sure, however, that it's a good place for BOTH of them, for fear of sparks igniting fuel fumes. <br /><br />Is there a safety concern about having the battery in the same compartment, or is this common practice?<br /><br />Thanks.

 

[12Footer]

Re: Battery and fuel in same compartment

Absolutely. That's a major no-no. I'm aware many boats have batteries exposed in engine bays and the like, but the key is to seperate and ventilate, if you cannot isolate.<br />Batteries give off Hydrogen which is what the Hinendburg zepplin was full of. One spark from the battery, and poof!<br />If you cannot isolate the battery by moving it, you can isolate it by using a battery box, and exaust fan to vent the lazarette before starting.

 

[webbwebs]

Re: Battery and fuel in same compartment

Thanks for your reply, 12Footer. That's kinda' what I thought, though I'm not real sure how to handle it. <br /><br />Because of the way that the lazarette is designed, it would be very difficult to isolate the two. I could remove the battery from the lazarette and place it belowdecks, but I suspect that would also be a bad idea, because of the battery fumes. Perhaps I can build a sealed battery box within the lazarette and vent it to the outside. Do you know if the fumes are lighter than air, or will I need to install a fan? Any suggestions? The boat is only a 20 footer, so I don't have a great deal of options.

 

[neumanns]

Re: Battery and fuel in same compartment

Hydrogen is lighter than air and gasoline fumes are heavier than air I believe, however in such a small area I dont know how important vent location would be.

 

[crab bait]

Re: Battery and fuel in same compartment

many boats are that way.. just put red/black plastic battery terminal sleeves/caps on the battery ,,alvailable at any marine center..<br /><br />also install ,if not already , 'claim shell vents.. <br /><br />one low facing toward oncommin' air ( bow ) .. one high facing stern.. also at marine centers..

 

[Boatist]

Re: Battery and fuel in same compartment

Sailin<br />Very common set up. Almost every open aluminum boat set up this way. Yes battery terminals need to have rubber caps and a battery box. Even if have fuel still need a flame or spark to set off. Make fuel tank has no leaks. If compartment is open to air like a small Aluminum boat then do not require vents or blowers. If area sealed or closed up then Coast Guard regs require both input and output vents and a bildge blower. Output vents hose should be as low as possible but high enough that it will never be covered by water. Input vent should be up high.