1996 Seadoo GTX 787 off idle big..

[Travisgg]

Hey guys Seadoo was running great and of course starts acting up. Fuel lines were all previously replaced as well as fuel selector switch, was winterized with stabil Marine. Compression both about 160. Starts no problem all the time, carbs just went through and thoroughly cleaned. Really cleaned. Pop off 26 and 30.
Just started bogging off idle all of a sudden, and when doing high speed runs it's running great for a while but then we'll just cut out and die but start up again no problem (then did carbclean). Thought the carb clean would fix the problem but no go. One thing noticed when pulling off carbs is the fuel was orange. Deep Orange. Started pumping some directly out of the tank it's normal color, but fuel water separator container was full of Orange fuel. Not sure if related but what the heck. Also doubled up on the stabil Marine just to see if it would help clean the ethanol. Engine sounds different kind of Pingy/knocky but seems to run fine. Ideas? WSM rebuild kit if you tell me to do mikuni I will just do it LOL

 

[mikidymac]

The fuel will turn orange really fast now days with the ethanol. Drain and replace with fresh fuel.

If you didn’t use genuine Mikuni parts and new needles and seats that’s 95% of the problem.

 

[Travisgg]

Roger that will do.

 

[Travisgg]

Alright here's an update. All is well!!! Replaced everything with genuine Mikuni carb kit and new needle and seat, and new Mikuni pop off spring just to be sure(research which spring you need). Perfect machine again. For anyone interested what could be the difference in carb kits...I did notice the big round black Mikuni diaphram is a different material than the WSM kit that was in the machine previously. Mikuni seems flimsier/thinner vs the thicker rubber material WSM uses. So in the end who knows. Maybe the machine just needed needle and seat, or maybe the diaphragm is really that sensitive and Mikuni's material is critical to proper operation.