This boat is having difficulty getting ‘on top’ or on plane. I have to wonder why the driver isn’t leaning forward toward the Bow to shift the center of gravity of the boat, thereby pulling up the Lower Unit and propeller to assist the engine. The physics of Surface Prop propellers is simple.
Instead of allowing the propeller to remain fully submerged as is done with most outboard engines, Surface Prop allows just one half of the propeller in the water when the hull is on full-plane.
This creates a major reduction in hydrodynamic drag from both the propeller and the rest of the lower unit located below the propeller.
Once the boat reaches it’s proper On-Plane attitude, the boat will increase very rapidly in speed.
Reasons why the boat can’t achieve proper Planing are simple – the dead-center of the propeller shaft is not at the correct height in relation to the smooth underside of the Hydroplane’s or Runabout’s hull. This is a very critical physical adjustment.
Improperly set, you will see what seems to be happening in this short video.
Disclaimer: This video is not my work, no copyright is intended.