On Fri, 19 Mar 2010 19:07:50 -0700 (PDT), Ted
wrote:

Hi All,

I have a 3.7 Mercuriser Inline 4cyl motor and have noticed an odd
behavior with it. When at the dock or on the trailer with a cold
motor, it will crank and start right up, but when the motor is fully
warmed up it often doesn't want to crank. I've read of others wth
this motor who get vapor lock in a hot engine but I'm assuming these
folks at least get it to crank, whereas mine won't even crank. I
think I hear the click of the solonoid trying to engage when turning
the key and that's all. Vapor lock doesn't prevent the engine from
cranking does it? If I remove the engine cover and allow it to cool
for a while, it usually cranks and starts right up. The cooling
system is closed so the temp sits at 120-140f max. I installed an
electronic ignition kit about 7 years ago and other than that the
motor is stock. Boat runs great once it starts.

Thanks,
Ted

If you're for sure hearing the solenoid and the battery is good, what
about the starter motor? It'd be interesting to see if it'll crank
over when hot using a manual starter switch. Maybe needs a rebuild or
replacement?