I have a friend whom wanted a new boat with a jet outboard like I run. Most of us in this area run jets because of the low river conditions around here. Anyway, to the point. He purchased a brand new River Rave with a 90/65 jet. Beautiful boat. He wanted me to break it in. We took it down yesterday morning and he dumped me in. I started the boat and it ran fine. It idled just fine but, when I went to jump it on plane it just revved up and pretty much sat there. We pulled it out and nothing was in the impeller, the nut was tight, etc. The only thing I can think of is there is something wrong with the key way on the shaft. Any suggestions? My buddy was furious. A 18000.00 boat that won't run can do that, you know? I am sure the dealer will take care of the problem but, I was just wondering what the guys in here thought.

Man that stinks. I run jets also and have had times where the intake was clogged causing a problem like your mentioning but if everything was clear I dunno....

Sounds silly but check the plug wires to see that all are hooked up. I bumped bottom one day and after the motor did as you descirbe. I would give it full throttle and engine wouldn't rev enough to get boat on plane. I pulled the hood and found a plug wire had come off, hooked it back up and boat was back to normal.

Another thought, is the outboard set to the proper height? I assume it is coming from a dealer but who knows.

A missing plug wire crossed my mind so we checked the wires, they were fine. The motor is at the right height as well. I am going to make him a plate like I have on mine to help push the water to the intake. Mine used to cavitate in rough water until I did this. His is like it should be, the top of the boot is 1/4" above the bottom of the boat while holding a straight edge along it. I am curious to what the problem is as well. I will keep you posted.

Shaft has got to be spinning, if not the boat would move. The problem will be between the motor and impeller. Sounds like the motor is runing fine. 8-)

Well, we picked up my buddies boat from the dealer yesterday and he found the problem. It would have been the last thing I would have thought about. They had a 115 jet housing bolted to a 90/65 motor. Evidently the tube that houses the impeller is  bigger and let water bypass it. They said it came that way from the factory. It all sounds a little fishy to me but, it works now. We had it on the river and it runs fine. Thanks for the replies.