Jump Starting from domestics...

[ditchcrawler]

 

It used to be common practice to have isolators in the Negative on boats, and two banks could be isolated with one switch if this were done.

It's rather frowned upon now, but I'll bet there are plenty of boats around which still have negative isolators.

 

Tim

Our last boat was like that but it was built in about 1992.

[helrow]

And... I'm off. Piece of cake. Just connected the domestic and starter positives as instructed. It melted the long necklace I used instead of a boring old jump lead when I started the engine though.

That was a (crap) joke. I went for the conservative jump lead over wet bit of old wire option...

[Arthur Brown]

Glad to hear! Even a small wire will assist to share the solar charge current with the starter motor, just it will take two days to reach fully charged if it's sharing five or ten amps with the other batteries.

 

Somewhere on the market is a jump start device that plugs into a cig lighter socket and has a small boost converter that sends 15 ish volts out down a wire to another lighter plug. While I hate lighter connectors the device would be a means of transferring charge from one battery to another. Taking 75AH from a big house stack shouldn't cause a problem but putting that 75AH into a single good start battery should give an easy engine start to begin a recharge. just remove the thin lead first.

 

Ultimately the OP needs to protect the start battery -even at cost! Modern engines don't usually have facility to start without electricity.

 

Maplin do a cover for a toggle switch, You could transfer the pump and lamps feed to the house battery, Maybe the switches for the lights and pumps could be hidden behind a nice wooden shield -whatever your boat's trim wood is. Maybe you could fit a rotary switch that doesn't respond to up or down movements.