SomeBody wrote:

Yea, how do you stop your engine now? What exactly happens when you
decide "it is time to stop the engine"? You probably press some button
or pull some lever, and then what happens?

i





Let me explain how my engine has the speed lever set, you slide the lever
down and tighten a knob (twisting) that passes through the lever. If I was
NOT present to monitor the oil pressure and needed to shut it down to
prevent damage to engine, who would turn this knob to release the lever?
You?



That is a pretty crude mechanism. Cutting off fuel to the fuel pump may
take
a minute to shut the engine down, which seems too long. You need to
modify this
speed control mechanism so it doesn't require tightening knobs.
Probably the best,
if this engine is manually started, is to use a solenoid that will hold
the speed
lever in the right position when the juice is on, and drop it when power
is cut off.
Wire an oil pressure switch with normally closed contacts (normal in
this case
taken to mean oil pressure OK) in series with the solenoid and battery.
After starting
the engine and developing normal oil pressure, you pull the lever to
operating speed
and the solenoid holds it. If the solenoid burns out, the battery goes
dead, a wire
falls off from vibration, etc. the engine will be shut down. You could
wire a
normally closed push button in series with the rest of the parts as a manual
shutdown switch, so you don't have to overpower the solenoid to shut it off.

If this engine has an idle position to the speed lever, you have to make
sure a
spring or whatever pulls it all the way to the shutdown position on oil
pressure
failure.

Jon