I have a guardian 15kw 0047602 that was connected to NG, but I did the conversion to propane. It started up great after about a minute or so it would shutdown with overspeed flashing. after about 3 cycles it is staying running now, maybe because it was sitting a while?, anyway it's running and I've got about 123v 60hz on the block now. The motor seems like a slight oscillation but the volts are steady. My first standby genny, is that normal or would it be constant. also if the power is constant should I mess with it at all.