Ground wire above garboard drain

[Debt-icated]

2010. 310 Sundancer Twin 5.0l….the issue I have is a ground wire that is fastened to a bolt directly above my garboard drain. I thought the ground wire looked a little loose so I attempted to tighten the nut but the bolt was just spinning. Turns out the bolt broke off the head. Does anyone know where the head would have screwed in from the outside of the boat? I thought it would have been the top screw of the garboard, however it’s not. Could it be behind that garboard?

 

[MonacoMike]

It is a bonding wire that connects all the metals to slow galvanic corrosion. Not sure how it was attached. Red is positive, black is negative or ground, and green is bonding…

 

[Bill Curtis]

2010. 310 Sundancer Twin 5.0l….the issue I have is a ground wire that is fastened to a bolt directly above my garboard drain. I thought the ground wire looked a little loose so I attempted to tighten the nut but the bolt was just spinning. Turns out the bolt broke off the head. Does anyone know where the head would have screwed in from the outside of the boat? I thought it would have been the top screw of the garboard, however it’s not. Could it be behind that garboard?

Typically. the garboard drain is secured to the transom from the the outside and well sealed to the transom. See picture.

I would imagine that screw should have gone from the garboard fitting , to the inside with that screw double nutted. One nut to hold the screw in place and one to hold the wire on.