Starter won't engage with key but works when hotwired

[Ubnpast]

Just picked up I believe a 1989 mercury 40, starter spins but bendix does not engage when starting with key.

I replaced 3 ground wires in motor which appear to have been melted, it seems like this wore came in and was split 3 ways, one to starter, solenoid bold and small nut on solenoid.

Bendix engages when hotwired, engine fires right up.

Test light indicated power was coming from ground of starter, did not check with volmeter yet.

It has a new battery and I believe this may be a ground issue, where should I look first?

 

[alldodge]

Just picked up I believe a 1989 mercury 40, starter spins but bendix does not engage when starting with key.

I replaced 3 ground wires in motor which appear to have been melted, it seems like this wore came in and was split 3 ways, one to starter, solenoid bold and small nut on solenoid.

Bendix engages when hotwired, engine fires right up.

Test light indicated power was coming from ground of starter, did not check with volmeter yet.

It has a new battery and I believe this may be a ground issue, where should I look first?

If you have power on a ground wire then you have a ground which is not grounded, its floating. Get a voltmeter and check from the battery ground.

The issue with your starter may be the starter solenoid/relay

 

[Ubnpast]

Problem has been located, battery cables were reversed, although should not have been (both are black, 1 with a white stripe should have been positive), cable must be reversed somewhere else in the boat as the bilge isn't working now.

To be continued.