Whenever you are having the problem of little or no speed and the engine is revving up normally you have a propulsion problem.
The most common problem is the wear is out of tolerance or the impeller is dinged up bad or one of the blades are bent.
Most of the time you can just put a new wear ring in and be done with it. Look through the jet pump nozzle and you will see the impeller blades. Around those is the wear ring. Clearance in between wear ring and impeller blade should not exceed 1.0 mm (.040 in). If it is more than this replace it.
It's an easy fix and can be done with a few tools. Only special tool you will need is an impeller removal tool, which you can order with your new wear ring for a few bucks.
Let us know how you make out. For more detailed instructions on disassemble of the jet pump do a search on wear ring removal and you will find a lot of information.
Give us a shout if you get stuck.
Ryan
