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2000 crusader 5.7 305 hp no wot

R

racmine

New member
Help! buying a used 2000 33 ft silverton sportbridge with 5.7 crusader engines. only geting 3900 rpms ,previous owner did not use boat or do any maintence, can this be just bad fuel in the tank. checked fuel filters ok ,new plugs ok , port engine just had a valve job boat ran at 3500 and 3700 rpms after valve job came up to 3900 rpms after new plugs, we think there is water in the fuel , tank is 3/4 full. I will need to run the boat untillI use up all the fuel and then start with fresh fuel any sugestions would help
is there a sensor that prevents the engines to top off at 3900 rpms
props are 18/20 are they the right size for this boat
I come up with to many possible causes ,fuel, fuel pump,wires, cap, rotor,water in fuel,wrong prop, injectors,sensors
will welcome any advice I love the boat and want to buy it
I had the boat surveyed, engine analayis doesnt indicate any engine related mechanically reasons
maybe someone had a similar problem
what should my WOT be 4500 rpm
 
Okay, then here's the drill:

Borrow (if you aven't got one) an advancing timing light (from Auto Zone). Check the timing at idle, then at 3,000 rpms. You should have abut 8 to 10 initial and at least a TOTAL advance of around 26 to 28 degrees. I suspect you don't.

Open the choke by hand, then the throttle (engine OFF). See if the secondaries on the carbS open all the way.

Do the Fastjeff Dyno Test: Set the cruise speed at, say 2,800 rpms. Open one throttle all the way and note the max rpms acheived. Return to the 2,800 rpm cruise speed (accurately), then open the other. Record its max rpm and compare.

If one motor is lower than the other it will drag down BOTH engines! If so, concentrate on that one.

Jeff
 
Call silverton to check on their "as installed" prop size. 2X on verifying the tachs. Did your survey include a separate, thorough "engine analysis" or did they just take an oil sample? If the engines will run at 3900 rpm, and remain smooth, water in the fuel is highly unlikely. May want to finish the rest of the tuneup items, especially given the history.

Another thing to check is how much 'junk' is stored on the boat. It is pretty easy to accumulate extra weight really fast with 'stuff'. Also, many builders will prop the engines with the boat damn near empty. that's fine is you use it that way. if you prefer all the equipment on boat, with full fuel and water tanks, get the props repitched.
 
It seems like the engines may be marginal for a 33' boat. They should still reach max WOT. The only thing not mentioned is the trim. Are you working the trim tabs to get the best operation?
 
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