Hi,

My MVVS 45 primes very hard when the tubing is empty of gas. She needs more or less 40-50 flips with choke closed and throttle open.
I changed the tubing and double checked the tank with no effect. The gas tubing length is less than 6 in and there is no air leakage.
Do I need to shield the small hole in the choke disk?
Since I have run only a couple of tanks through this engine I use the included oil at the recomended 30:1 mix.
Using a Bisson muffler with all buffling removed I get 6760 RPM on a Menz 22x8 on the second tank.
This is approx. 4.1Hp according ThrustHP (more than 1Hp less from the listed power).
How much improvement should I expect while the engine breaks in and going to 40:1 mix?
Is this big lack of power cause of the Bisson muffler ?

Thanks

Angelo