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We are experiencing trouble with our motor in the lime green batboat you see in my avatar.

The trouble began at the race in Savannah, GA. We were running along just fine, and all of the sudden the motor seemed to die out (seemingly from flooding). The only way to get it going again was to kill the ignition, and restart the boat, but the interesting thing is that you had to pump the throttle as if it had a carb., before the boat would start.

It seemed to run okay in Cleveland, but in Corpus Christi, with two laps to go, it did it again. This time, however, when the boat was restarted, it would only run 3800 - 4000 rpm. We finished the race, but never reached full RPM the rest of the day.

The boat was then tested prior to the Bahamas race, and seemed to be "normal". We led the first two laps without any problems, but then the damn thing shut off about 2 times per lap. Sometimes restarting and able to run full RPM (4600 - 4800), and sometimes it would only run at 3800 - 4000. It seemed to occur when we would take a big impact from landing after being airborn, or as we would let off to take one of the tighter turns.

Now the boat will shut down while testing after 3 - 5 minutes, and run in what I have heard people call "slow mode".

I talked to a Volvo tech, who thought the problem might be a temperature sensor on the exhaust riser, but these engines are not fresh water cooled, so they do not even have the sensors. Others have opined that it may be a water temperature problem, but replacing the impellar did not solve the problem, although the boat ran a bit cooler.

Also, the oil pressure sensor and the knock sensor have been removed.

If you have any idea what may be causing the problem, we would greatly appreciate your input.

I don't know anything about engines, but my throttleman, Chris Gatturna from Page Racing it quite knowledgable, and could speak technically to anyone who will help.

Thanks in advance for you help! I need this thing to run right for Worlds in Key West.

rjcardinal

I am not familiar with the Volvo system at all. If it does go into a limp mode there has to be a way of finding out whats putting it in that mode.

I had a boat that would cut out right as I would crash back down after I would get some air. Turns out it was the main engine harness connector getting loose (Merc). I found it by cranking the engine letting it idle then I pulled on every wire I could find. As soon as I began mooving the main harness the engine died. Im sure you beat that Batboat pretty good at a race, maybe somethings loose.

Good luck and post what you find,

Ron

rpm

My Opinions:

1. Determine if its fuel or ignition related. Check fuel pressure on both the low and high pressure pumps. If memory is close, low pressure should be 12-14 psi and high pressure 26-30 psi...maybe more on the high side.

2. Lots of banging around, check all major electrical connections - ie....battery terminals, main engine harness, battery switches, starter, fuseable link, main circuit reset, ignition switch. Bypass safety tethers for TESTING ONLY

3. Take it to a qualified service center! They can scan the system for codes to start with. You may have your answer in 15 minutes.

Good Luck

Rod

Just Browsing

Thanks for the input so far.

I think they have tried most of this, and the problem seems electrical, and not fuel related.

28SS

I had the volvo 5.0 efi would do simular thing . did all the fuel stuff
and finaly figured out the coil was bad. when it would get warm it would drop voltage.