Octane level is not the problem.
Are you using the same carb for gas and glow ?
Walbros need a pulse for the pump, where are you getting it ?
Walbros made for 2 cycle engines won't work with a 4 cycle..It takes a special Walbro, one made for a 4 cycle weedie...
and you still need a pulse from the engine...[8D]