Problem Solving a 07 Merc 4-Stroke

[bassmann77]

Took my boat out for the first time on Saturday. Got it to the lake and it wouldn't start. The starting battery was fully charged when I left the garage and I didn't have any accessories on. I then pulled the two negative "accessory" wires off the battery and the motor started right up. As soon as I stopped the motor, I couldn't get the motor started again.

I put the starting battery on a charger and brought it out to the lake today. It wouldn't start with the two accessory wires attached together on the negative post. So I took one of the accessory wires off and it started up. I then attached the other negative wire while taking the other one off and it started. When I attached both the accessory wires on together the motor wouldn't start.

I am guessing there is a short occurring when both the wires are together, but where do I start?

I have tried another battery and the same thing is happening. I am hoping that it is something simple, but with my luck it will be difficult.

Thanks for any help!!

Sincerely,

Luke

[bassNspear]

call local merc dealer and ask, if its under warrenty, i would have it checked

[marine_man]

Any idea what your two accessory wires are for?

marine_man

[muddpuppy]

I would check the wires with a volt meter. I wounder if the one neg wirre has a positive current? Just my shot in the dark.

[bassmann77]

I know for sure that the one wire controls the fuel gauge on the dash, and I believe the other one controls the switches on the dash.

[marine_man]

Can you tell me what year and brand of boat you have?

marine_man

[bassmann77]

I have a 2007 Alumacraft Dominator CS 175.

[boatfixer]

Its odd that guages and switches would have separate grounds running all the way back to the battery. I personnaly would trace them back to see where they go.

[marine_man]

Right on Bruce... I agree.

It seems a bit odd that one ground runs directly to the gas gauge on the dash, with a separate one feeding the switches / instruments.

I'd take a test light or a multi meter and verify that they are in face ground wires.

Any idea which ground wire is causing the issues, and what that wire runs to?

marine_man

[bassmann77]

That is my next step. The boat is tied to the dock, so I am heading there tomorrow. My Dad was there tonight and my bilge pump wasn't working. I don't know if that means anything, but it might.

As to the guages, what I know at this point is one of the wires is the gas guage but it might also be the ground for other things.

This should be interesting to find out with the test light to see what power is going to where.

Thanks guys for helping me think through all the possiblilities of what it could be. This is what makes this site great.

Sincerely,

Luke