Good point on the fuel shut off solenoid Brad. My CV15 on the Deere does not have that option so I did not think about it. But some variations do. Here's what the manual has to say about them:
"Fuel Shut-off Solenoid (Optional)
Some gasoline-fueled engines are equipped with the
optional fuel shut-off solenoid, which is installed in
place of the bowl retaining screw, to eliminate
backfiring when the engine is shut down. If a solenoid equipped
engine will not start, check whether sufficient
voltage is reaching the solenoid. A minimum of 7.3
volts DC is required to activate the solenoid. Also
check to see that the ground lead from the carburetor
body to the air cleaner base mounting stud is properly
connected. If these check out, the solenoid should be removed for
bench testing. Remember to shut off fuel supply and
catch any fuel spilling from the carburetor as the
solenoid is removed. Bench test the solenoid by grounding the solenoid
case and applying 12 volt DC to the spade terminal. If
the plunger does not retract in this test, the solenoid is
faulty and must be replaced. Always use a new fuel
bowl gasket whenever the solenoid is installed. Refer
to the appropriate wiring diagram in Section 8 for
connecting the fuel shut-off solenoid."