I have a 1.80 mounted inverted. my starter won't turn it over either. I used to wire two 12 volt batteries in series for more power, but now I just open the throttle wide, plug the muffler with my thumb and slowly hand crank it few times. You can hear fuel being sucked into the carb. Close the throttle to idle (I have on board glow) and flip the prop backwards against compression. Occasionally it starts in reverse, but sometimes it kicks back forward. If not, I just hit the kill switch and start over. Sometimes it's not necessary to re-prime. Thing I have to watch is the on board glow--I've had it kick on me just pushing the prop up to compression. Least I know it's ready when it does that.

Luck.

Greg