richard wrote:
the last couple of times i took my 1993 25 ft I/O Fourwinns and went
around 25 MPH (4000rpms) the engine revved up and the boat slowed down
as if the prop was slipping. the first time I thought that I may have
hit a line but since it happened twice I think that something is not
right. at slow/medium speeds it is fine. Any ideas at to what is the
problem? Do you think that the prop/hub is slipping, and if so what can
be done? Could it be the transmission? any other ideas. We will be
hauling the boat out of the water in a few more weeks (darn that NE
weather)

Rich,

Is the boat an outboard or I/O? If it is, and I suspect that's the
case, you have a loose bushing in the prop hub that needs to be
replaced. Their's a rubber bushing that's pressed into the prop, to
keep hard impacts on the prop from being transferred into the
transmission (the bushing is cheap compared to the cost of a
transmission/gear assembly). Remove the prop and bring it to a prop
shop, it's not very expensive. Now's also a good time to consider a
spare prop, even if you've got a stainless prop, a good spare aluminum
one can save the weekend for not that much cash!

John