Well, the water's hard and my Sportjon sits out back in the cold darkness of a snowless Alaskan winter. But I think of her often. In the waning weeks of this past summer's boating season, a problem arose with the engine. I have a 2006 Sportjon with 200 hours on it. I had run the boat without incident all summer except for failure of the initial lift fuel pump. A replacement pump easily corrected that issue. However on one of my last boating trips, the engine suddenly beeped loudly and the engine cut off. I was heavily laden and running her at about 4900 RPM. I placed the shifter back in neutral, and the engine easily restarted. It would run fine until I crossed 4000 RPM and then once again the engine would beep loudly and abruptly shut down. I repeated this process about ten times with no change. The temperature gauge wasn't high, but it really never seems to move much at any time.
I unloaded the boat. With a hand winch, I was able to roll it up on it's side to check the jet intake. It was clear. The oil was full as was the reservoir on the side of the tank. I took off both the spin-on fuel filter on the engine and inline Racor fuel filter and inspected the fuel in a glass jar. All appeared normal. I dumped it anyway and reinstalled the same filters. About 45 minutes later, I restarted the boat and opened the throttle gingerly. At 4000 RPM, she abruptly beeped and shut down. That seemed to rule out an overheating problem. (I don't have any type of heater on my boat either).
Naturally, I was downstream from my vehicle. So, I left most of my payload behind on the bank and was then able to barely plane the boat at 3900 RPM to make it back to the launch. It ran fine at that RPM. It took about an hour. Once back at the truck, I pointed the boat upriver and opened her up to 5200 RPMs. She ran like a race craft with nary a problem! The next day, I returned downriver to retrieve my gear and ran it at all power levels without incident. I then winterized the boat and parked it for the winter. But I still think about this problem. In fact, it's eating at me.
I called Compeau's and they basically listed four possible scenarios that could cause this problem: low oil pressure, blocked coolant line, sensor out of spec, or water in the gas. Earlier on the day of the engine malfunction, I had run the boat through some heavy weeds and had to clear the intake. However, the sudden loss of power occurred more than an hour after my last weed blockage (and the grate was clear- could I have had a micro blockage in the engine coolant system?). I was also running the engine a lot harder than usual due to my load. I usually run it between 4200 and 4400 RPMs, not at 4900.
I am seeking advice from this forum as to what to look for as my trust in my engine is not high right now. Due to where I live, I am unable to take it to a dealer to have it checked out. How can I diagnose and correct this problem to avoid a similar failure in the future? Your thoughts?