I would like to know the proper way to start an outboard motor without
actually starting the ignition of the motor. I am doing this for two
purposes: (1) Do a "load test" on a battery to see how much life the
battery still has remaining. (2) Check the water pump in the lower unit
without risk overheating the engine.

According to the book "The 12-Volt Bible for Boats", the author
suggested the way to do a load test on a battery is by using the
starter as a load without starting the motor. What he said to prevent
the motor to actually start is "disconnect the primary ignition wire
that connects your ignition distributor to a small terminal on the
ignition coil to be safe." I don't understand this in the context of
an outboard motor. Did he mean turning off the "kill switch" (lanyard
stop switch)? Did he mean unplug the wire from all the spark plugs?

I keep having problem using flushing earmuffs to flush the lower unit
of the outboard motor. I cannot see the telltale water stream coming
off from the outboard motor. I can get around with this problem by
running the motor in a small water tank. However, using a flushing
earmuffs is surely more convenient. I want to try a flushing earmuffs
kit that is specifically designed for my outboard motor (Mercury Marine
Outboard). But I want to avoid overheating the motor in case the
flushing earmuffs kit doesn't work. Therefore, I am looking for a way
to start the water pump (in order to see the telltale sign) without
actually starting the motor when I am testing the flushing earmuffs
kit.

Thanks in advance for any info.

Jay Chan