97 Sl 1050 Running Problem

[JRB]

I have been trying to diagnose an itermittent but annoying running problem for most of the summer.

The engine runs strong and well all day - BUT when hitting waves hard at full throttle , the engine will stumble , and RPMs will be limited to 4500 until I back off the throttle , and let it return to idle for a few seconds. Then I can nail it again.

This problem will not occur if I am running hard on very SMOOTH water , so I do not beleive it is a fuel problem.

What could be causing this?

Any suggestions would be appreciated.

JR - in Holland , MI.
1997 POLARIS SL 1050.

[99gp1200]

Re: 97 Sl 1050 Running Problem

Have you tried running it on reserve?
Could be the fuel pick up for the "on" position is shorter than it shoud be
and its sucking air in the rough stuff

[JRB]

Re: 97 Sl 1050 Running Problem

I bypassed my fuel shut-off valve about 80 eng. hrs. ago - when I installed a new SBT engine. I ran all new fuel lines wherever possible , to eliminate any splices.

At that time I also discarded the oil pump , and kept the oil tank about 3/4 full.

I have visually inspected all fuel lines , and checked the crankcase pulse lines for looseness ,and/or cuts.

A few weeks ago , I cut the oil level sender wires and installed a 33 ohm resistor - thinking that maybe a bouncing / defective oil level sender could be messing up the computer. My oil gauge now stays at FULL , but the problem did not change.

JB - IN HOLLAND , MI
1997 SL1050.

[craig connolly]

Re: 97 Sl 1050 Running Problem

Well sounds like you have covered the basic fuel diag.that I would run in my shop also, I know this sounds crazy but I had a ski in the dealership where I used to work that done the same kind of thing, it turned out to be a shorted ground wire! the wire was fine in smooth water but when you got into choppy water the ground wire would loose connection! no real likely gonna be the prob if all your guages stay illuminated during the problem, but Its just a thought!

[John Kubiak]

Re: 97 Sl 1050 Running Problem

.... it turned out to be a shorted ground wire! the wire was fine in smooth water but when you got into choppy water the ground wire would loose connection!....

Wouldn't that be an open ground wire...... as a good wire will read the same as a "short" (close to zero ohms)

[Technical Support]

Re: 97 Sl 1050 Running Problem

If the over heat sensor is tripped it will rev limit the ski and it will not reset until the boat comes back to idle or cools down. If you are bouncing around and the pump keeps coming un hooked your getting the ski pretty hot. Your rev limiter is tripping and the regulator/rectifier or the CDI is what does this. Check all of the cooling system for restrictions and if all is well you might be running into an issue with CDI, you can disconnect the gray wire from the CDI to the electrical board and see if the problem still exists. Post back and tell us what you come up with. Tom SBT ( remember that the gray wire disconnected will not show if you over heat).