If you commenting on this video years later...the root cause of the problem is mentioned many times in the comments and here is the evidence of the failure:
• If your Briggs and Stratton Intek V-Twin o...
The engine's model number is 44S777-0016-G1 and the applicable Briggs and Stratton service manual for that engine is 273521
Initial Diagnosis:
Governor spring pulls the throttle open when the throttle lever is opened but the engine immediately starts to race/over-rev and will not idle after starting.
I am able to hold the throttle closed by hand to force it to idle but as soon as I let go, it wants to over rev. I don’t feel any force or movement in the governor linkage when the engine is operating.
The shaft play in and out as shown towards the end of the video at 1:48 is not indicative of a failed governor. Where that play is coming from makes total sense once I have taken the engine apart: • If your Briggs and Stratton Intek V-Twin o...