Bolt size for the negative ground wire for a 1987 85hp Force outboard.

[Long Island Boater]

I just purchased this motor ($50.00) for my 14 yr old son & I to work on, sitting in the mud but looks semi complete, and it is not frozen.
My first question is (On this forum) what size bolt connects the negative battery cable to the outboard housing? (it is missing)
Thank you in advance....
JB

 

[tommarvin]

Welcome, IDK, we have a 125hp.
It could be a 1/4 -20 put a punch in the hole for length.
It may be a 5/16 -18 punch for the depth one inch sounds about right.
Make sure you get a SS cut lock washer to go between the cable and the bolt head, coat everything with dielectric grease to stop corrosion.
Put anti seize on the threads so you can remove it later.
Buy a 1/4-20 and a 5/16-18 one of them should work.

 

[Long Island Boater]

Thank you!

 

[jerryjerry05]

5/16 1/2in