I believe that prop was developed for the OMC 17 with the 88 HP V-4 I/O ( 2 stroke).-----Needed to get a heavy load on plane.----Also used on outboards when there are power issues.
You stop it by turning the handle.----Post your compression values.----These motors are just so easy to get running ---" great " ---if they are in good condition.
??----The VRO is operated by PRESSURE pulses.-----The VRO uses an air motor.----Failure of the fuel diaphragm does not always result in fuel going into the crankcase.-----Trouble shoot the fuel system.----Find the leaks.-----
No----I do not see rapid failure.-----I would say you need to look for other issues in your fuel system.-----To long a fuel line.----Too many filters.-----Plugged pick up tube in tank .----Low crankcase compression etc.