I am seriously considering a jack plate for my 20 foot riverboat so I can run a prop and improve mileage and load hauling when conditions allow a prop.
Particuarily on some longer trips I am hoping to do.
To my understanding it does not optimize the jet very well?
I would like to hear some comments from anyone that has before and after experience with a jack plate as far as how it affected performance with a jet????
My buddy had one on his 20ft alumacraft. Terrible performance until I talked him into taking it off. With the jet it just put the foot too far away from clean water.
Yes, performance can be poor because the foot of the jet is too far from the transom or tunnel of the boat but this can be remedied by bolting an aluminum plate to the trim tab on the bottom of the transom so that the leading edge of the foot is once again an inch or less from clean water (and 1/4" below the bottom of the boat. Some folks bolt a plate on there even when they don't have a jack plate.
When you reinstall your prop gearcase, unbolt the alum. plate and drop the jack plate down.
Had one on a Grayling to do the same....prop for the big loads and economy.....jet for the skinny water.
The jet just seem to cavitate a bunch, especially in the turns.
The other thing is the range of travel needed to be closer to 7 or 8 inches of travel to get the prop down where it would run correctly. Also depended on boat load.
Overall the setup was finicky.
So, It sounds as if they will work ok If the bottom of the hull (or the top of the tunnel) are extended to carry the water back to the jet foot?
No other problems with the motor sitting back 4 or so inches?