flat battery

[Guest]

i have a pair of 100 amp leisure batteries on my boat 18 months old, as always i went out yesterday starting the boat both engines starting as normal,i hadnt started the boat for about 3 weeks but showed no starting problems i.e. sluggish turning over etc. both meters showing 13 to 14 volts as normal after starting. then a 30 minute trip to fishing mark, then 2 hours later we moved,10 minute trip as usual starting perfect then fishing for 4 hours as normal with my gps and vhf on then,i went to start and not enough power to start either engine.left it a while tried again and the same,got towed in put on trickle charge overnight,this showed 50% today and started showing 13-14 volts as always.why did this happen to both batteries? even though they arelinked surely both could not be faulty? any help.

 

[Guest]

If batteries are linked. If one goes, they all go. You should have batteries for domestic and seperate batteries for starting engines. I carry one red jump lead then if engine batteries go down I can start on domestic. buy a hydometre or what ever there called from garage shop and test them.

 

[Guest]

A dedicated starting battery, plus the facilty to link the domestic batteries to the starter in an emergency is a good idea.

I have a basic setup comprising a 1/2/both/off battery switch, 1 car type cranking battery and 1 100ah leisure battery. I find this works well for my needs.

I also carry a 12 'power pack' which is useful for all sorts of things, including starting the engine if I somehow wind up with both batteries dead.

 

[Guest]

Have you checked the water levels in the batteries? I've always been led to believe that if the level's low the batteries will very quickly lose their charge. Top up with distilled water, not ordinary tap water.

 

[Guest]

OH clever girl