Starter sticking causing FIRE !!!

[GreatWhite]

I have an older Onan diesel genset. I tried starting the unit last time I was on the boat. I heard a solenoid click but nothing happened. I had a mechanic come and check it out and he just jiggled the linkage coming off the solenoid and it started fine.

The mechanic has suggested I put a new solenoid on (which I have purchased and am about to install.) He was VERY concerned that I couldn't seem to shut the power off to the starter motor, even when I turn the big battery switch selector to off. It appears the starter on the Genset is wired directly to the battery.

His concern is that this older starter/solenoid/bendex would jam at some point with the starter engaged into the flywheel there by turning the start motor into a generator and feeding current back into the battery and wiring causing a fire.

Is this normal? Has anyone else dealt with this and what should I have in place. Would a simple battery switch suffice to allow me to break the circuit manually?

[Capnblu]

When the engine fires it will drive the starter sprocket down its driven shaft, disengaging the flywheel and starter. Replace your solenoid, wire it properly, get a real mechanic.