Just got a 1985 pro craft with a mercury 200. I’m not worried about speed too much. My son and I can cruise from fishing spot to fishing spot around 25 mph and be happy. The prop is a 4 blade 26 pitch. It seems like the motor is screaming and takes forever to plane out. Once it does it takes off. I think I am burning A LOT of gas just trying to get up.
should I trade props???
what pitch should I try out??
Without reading other replies, my knee jerk reaction is that you have a SS ported prop and the holes are too large, or the engine is sitting too high on the transom for the way you drive, or you are coming up with the trim too far out and if that would be the case tossing a good rooster tail till up and gone. I didn't add a spun propeller hub as you said once it locks up you are gone. Spun hub would not do that.
Ports allow exhaust gasses across the blades which reduce the density of the water allowing engine HP to develop rapidly and in doing so make for a quicker hole shot with less load on the engine at that time. Then once up, water velocity running past the ports seal off the ports and the exhaust is out the end of the barrel where designed. If you are running with the ports sealed and you slow down to the point where the oncoming water pressure isn't sufficient to seal the ports, the bypass function will reintroduce itself and you will return to high rpms and slow forward speed.
Engine sitting too high would contribute to ventilation; prop sucking in ambient air which accomplishes the same thing as ports and if you have both ports and excessive height, you can really experience what you said you have.
Trim out too far allows the engine to once again suck in ambient air and is associated with initial porpoising (bow oscillating up and down) as the hull exits the water. As speed increases, which on a light hull with a 200 hp mil, could happen in seconds, the porpoising amplitude and frequency are reduced until the speed catches up to the trim angle and the boat takes off....all in a matter of seconds.
My 2c
