Have you tried the extra fuel device?
If you haven't, pull the throttle lever back towards the cylinder (fuel off position), lift up and hold the round knob located on top of the crankcase and next to the throttle lever, next push the throttle lever away from the cylinder until it stops. Next, release the knob you were holding and it should stay up.
This is the extra fuel cold start position. Crank engine as usual and if it starts, the governor will kick the throttle back towards the cylinder and either reduce the engine RPM or shut the engine off completely, depending on the throttle.
On most of my E79's the throttle will stay where you set it, but on one of them the throttle is spring loaded and the engine will run slow if I hold the throttle, but the moment I let it go the spring reduces it to no fuel and the engine shuts off.
Just my .02c