cavitation problem

[bartkw]

my buddy got a new maverick hpx recently. the boat originally had a yamaha four stroke 90hp installed. he had the dealer switch out the motor to a yamaha 90hp two stroke. the boat is a pocket drive hull and he has been having a major problem with cavitation. when the dealer switched the motor he used the prop from the four stroke. my buddy got that replaced last week with the proper prop according to maverick specs (what the dealer says), but he is still having the cavitation problem though not as bad. he went from a 19 pitch to a 17 pitch or vice versa maybe. will lowering the motor on the mount help with problem? when you look at his boat the motor seems to sit high so the shaft is not that deep in the water. would anyone have recommendations to help solve this problem.
thanks,
mike

[Bay Catt]

Does it have a cavitation plate on it? If not get one. Lowering the motor should help.

[bartkw]

it has a cavitation plate (factory)

[Hamfisted]

Bart go over to the Maverick website and check out the forum, ask questions over there. There's some folks with the same boat and have dialed in the correct prop for that boat. You can take a look at the Maverick performance bulletin here: http://www.maverickboats.com/perfbull/03-40-MAV-C.pdf to get an idea. They used a 3-blade Yamaha Pro Series 13 1/2 x 19 prop on their test boat. A 4-blade prop will give him a better grip out of the hole, but some people like to stick with a 3-blade trying to get that little extra top end. If you run less that WOT most of the time then I think the 4-blade is the way to go.


-Mike