75HP No key start, no guages, no trim

[Waldguy]

So my 2002 75HP motor stranded us on the lake. On the last trip home, the key turn was unresponsive. No click, no nothing. I jiggled the shift lever, etc. I also tried to tighten the battery cables.

I DID get it started shorting the solenoid terminals -- it turned over strong. We enjoyed a porpoising ride back to the dock. NO RPM guage. Bilge pump, and livewell pump working.

The battery was fully recharged overnight. No difference. Any ideas as to the best place to start looking?

 

[Chris1956]

Most Mercs have a fuse that controls power to the ign key. The ign key powers the starter solenoid, but not the ign. You might look for a blown fuse and the most important reason which is a bare wire rubbing ground or another kind of short circuit. If no short, the fuse would not blow.

 

[Waldguy]

Thanks Chris. There is a 20 amp fuse at the top of the motor, which does control the power to the ignition, as well as to the trim motor. It was blown.

Replacing the fuse fixed the issue for the present; I can't find the short yet. Strange thing is, the start never even attempted before quitting. Trim was working fine until the attempted start.

 

[Chris1956]

That fuse should only power ignition, gauges and the trim relays, not the PTT motor itself, I would think.

It makes sense to trace the PTT relay wires from engine harness connector to the relays themselves. Look for any that rub on the block or cowling.