Background: I have owned many boats over the years but all of them have been prop driven (I.O. and outboards). Always wanted to try a jet, but had no real experience with them. I recently took the plunge and purchased a used 2004 Boulton 22' skiff. The boat has a 496 Vortec 8100 with 180hrs, closed cooling, and Hamilton jet pump on it. The first 2 times I took it out was on a lake and the boat ran like a striped ass ape (loud and fast)! The next time I took it out was on the delta. It ran great, starting and stopping several times, but then I went to start it and sucked up weeds and debris into the grate which immediately caused it to loose thrust and revved the engine up high. I had a barge coming toward me so I quickly hit it into reverse to try to clear the grate, which restored some power and I was able to get out of the way. I shut the engine down and used a rake to clean the rest of the debris from the grate and continued fishing using the kicker. At the end of the day I went to start the engine up and heard an intermittent knocking in the back of the motor, as I tried to rev up to get on plane, the knocking got louder and louder the more RPM's I gave it. I went back to idle and tried to locate where the knocking was coming from. At first I thought it was a rock or something that had gotten sucked into the pump or engine water passage ways as the knocking was intermittent and sounded like a marble or rock bouncing around in the back right side of the engine. I could not tell if it was coming from the valve cover or the bell housing in front of the pump. I then thought I might have bent a push rod, but the sound is intermittent and sounds more like something rolling or bouncing around, not the consistent tapping that I have heard with bent rods or valves. I shut the engine down and restarted it several times, but still had the knocking sound. I did not want to do any further damage to the engine so I used the kicker to get back to the dock, took forever as I was about 10+ miles out. Anyway, I am hoping I did not do anything major as I do not have the funds to do major repairs. Any suggestions on what it might be, what I should check, or any suggestions of a good reasonable mechanic who has experience with these jets in the Central Ca region? Any help would be appreciate! Needless to say, not a good start into the jet boat world! lol
Thanks again!
