Mercruiser ground wiring question

[othelloears]

I am reinstalling my 1984 mercruiser v8 5.0 228 and can't figure out where three ground wires run/go.

1) Where does the black main battery ground wire attach to the engine?
2) I have a long thick black wire coming off the flywheel ground stud on the back right of the engine. I know the smaller one on that stud runs to the gimble housing but where does the long black one go. I assume it may go to the same engine stud the battery cable goes which would explain why they are both off.
3) I have a small gauge green wire on an engine ground stud on the middle left side of the engine

Please help!

 

[Bondo]

Re: Mercruiser ground wiring question

Ayuh,... #1) goes to stud #2)....
The green wire might be the fuel tank bonding wire which will go to the motor block..

 

[othelloears]

Re: Mercruiser ground wiring question

The manual lists two engine studs...the flywheel housing AND??? Where is the other one. Does it attach to the from motor mount. Thats the only other thing I can think of that I would have removed when I took out the engine.

 

[Bondo]

Re: Mercruiser ground wiring question

The manual lists two engine studs...the flywheel housing AND???

Ayuh,.. There's Usually 2 combination bolt/ studs, at each aft corner of the block...
The 2 Outsides of the flywheel cover....

'ell,... ANY drilled,+ tapped drilling in the block'll Work....

 

[othelloears]

Re: Mercruiser ground wiring question

I only had one of those. The black wire attached to that must run to the engine stud and attach with the battery gound on another engine stud. What bothers me though is that I would have had to remove it to get the engine out which is why I think they may both have been attached to the from engine mount.

Anyone have any ideas where that green one runs from the engine stud too what?

 

[Bondo]

Re: Mercruiser ground wiring question

Anyone have any ideas where that green one runs from the engine stud too what?

Ayuh,... Reread post #2...

 

[othelloears]

Re: Mercruiser ground wiring question

Ok so I have the battery cable, small gimble/transom ground and long black thicker cable on the flywheel stud but where does the other end of the long black wire connect to?

Any guess where the green one connects to from the engine block?

 

[Bondo]

Re: Mercruiser ground wiring question

stud but where does the other end of the long black wire connect to?

Ayuh,... It sounds like another battery ground cable....

Any guess where the green one connects to from the engine block?

I Already answered that in post #2.....

 

[othelloears]

Re: Mercruiser ground wiring question

Is it possible the other black cable runs from the flywheel ground stud to the power trim pump?

 

[Bondo]

Re: Mercruiser ground wiring question

Ayuh,... Anything is Possible...
The trim pump is Usually wired directly to the battery posts...