grounding issues

Hi, i'm having a grounding issue with the electrical system on my 88 johnson 60hp 3 cyl outboard i bought the motor recently and mounted it to a 18 ft aluminum starcraft i saved from the scrap yard , i never saw the motor hooked up but had it running briefly until the vro warning went off and it shut down i recently unhooked the vro and ran it yesterday for a minute , but my issue is the ground... Im running it with 2 batteries on a selector switch, grounded the batteries to the frame on the inside of the transom and ran a 16 g jumper from the batteries to the ground on the power head and it started right up but the jumper wire i used for the ground wire burned up, and i know i did somthing very wrong like i said i never saw it hooked up saw im just taking stabs in the dark , i went over the manual a hundred times and it tells very little about grounding the batteries accept to ground to the power head , i need to know the gauge wire to use and where and how to ground it ,any help would be greatly appriciated ...Thanks

Re: grounding issues

You need a large(6 or 4) negative cable ( black) from the battery to the engine. Same size as the red wire from the positive to your starter solenoid. I would unhook the wire to the hull.

Re: grounding issues

Yes unhook the ground to the transom, do not use the hull as a ground post, run a the proper ground cable to the engine block.

Re: grounding issues

Maybe Iam wrong, but all the info I have seen & on my 2005 18' North River the ground is not connecterd to the hull of the boat. The ground from the batteries go to a separate terminal block & then all the ground wires are connected to there.

The motor has to be grounded so the starter will function, & it would also seem that thru this ground you would get some grounding to the boat by way of the motor's mountings.

Re: grounding issues

Thanks, should i run a ground from each battery or run them to a junction and then to the motor ? because its a small grounding post on the motor ...

Re: grounding issues

Where are you running the positive cables to. Are you using one battery for a trolling motor or something?

Re: grounding issues

Im running the positive from the battery to the selector switch and the positive cable to the motor from the common post on the switch... my trolling motor is gas ...

Re: grounding issues

Join the battery negatives together then run a single negative to the engine block.

Re: grounding issues

Thanks for the good info , i spent the afternoon with a spool of 4 ga cutting and crimping and got it runnin... i must have disconected the vro right , no buzzer and no shut down , i still have some work to do though , i noticed the bottom carb is pouring fuel out of the side , but this boat may get in the water this year ...Thanks Alot !!!