Stud below inner Transom plate

DarkMantle

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Hi there. Not sure if this is the right spot for this question. I have a 2007 Chaparral Signature 270. The motor and transom assembly are currently removed. It's a long story. A Hack owned this boat before me. Anyway, there's a stud right below the inner plate in the fiberglass. It's about 3" long and probably a 10 or 12-32 with a locknut. This stud has a 10Ga wire that went from it, over to the negative post on one of the batteries. The nut wasn't even tight on the stud for starters. My question is, what is that stud for? Is it simply just a junction point? If that's the case, what else is supposed to be on it because it was just that one wire going over to the battery.
 

Scott Danforth

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If the wire is green, it's a bonding screw
 

Bondo

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It is indeed green. What is it bonding? Is the bonding wire from the new transom assembly supposed to go to that, then over to the negative battery terminal via that green wire?
Ayuh,..... Welcome Aboard,...... Any chance there used to be an anode plate outside the transom, in-line with the stud,..??

The bonding system ties everything metal on the hull, to the engine block, includin' the fuel fill, 'n tank,.....
 

Scott Danforth

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It is indeed green. What is it bonding? Is the bonding wire from the new transom assembly supposed to go to that, then over to the negative battery terminal via that green wire?
Start googling IMO and USCG websites and regulations on bonding and learn about one of the most important systems on a boat
 

DarkMantle

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Start googling IMO and USCG websites and regulations on bonding and learn about one of the most important systems on a boat
I understand that it's a bonding wire as opposed to a ground. I get what the premise of it is. However my issue is that, as previously mentioned, a hack had this boat. I'm trying to get it back to factory spec and I don't really know what that it. I have the merc manuals but they don't appear to touch on this part with regards to my boat.
 

Bondo

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I understand that it's a bonding wire as opposed to a ground. I get what the premise of it is. However my issue is that, as previously mentioned, a hack had this boat. I'm trying to get it back to factory spec and I don't really know what that it. I have the merc manuals but they don't appear to touch on this part with regards to my boat.
Ayuh,...... As I mentioned, it either was attached to an anode, or was used as a buss point to combine wires,.....
 

DarkMantle

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Ayuh,...... As I mentioned, it either was attached to an anode, or was used as a buss point to combine wires,.....
Pretty sure it's a bussing point. It was not attached to any anode. I'm thinking it was the stainless wire from the inner transom plate that was supposed to be attached there, then over to the battery. It's literally a stud into the fiberglass. There's no metal there. Seems a bit odd to me to do it like that when they could have just used the back of the engine block.
 

Bondo

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Pretty sure it's a bussing point. It was not attached to any anode. I'm thinking it was the stainless wire from the inner transom plate that was supposed to be attached there, then over to the battery. It's literally a stud into the fiberglass. There's no metal there. Seems a bit odd to me to do it like that when they could have just used the back of the engine block.
Ayuh,...... I agree, completely,.....
 
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