95 GTX won’t run full throttle

[thomas0202]

Ski has been sitting since summer of 2018 since I didn’t have time to ride last year, so I pulled it out and changed the fuel lines, cleaned the selector valve, and changed the plugs. Took it for a test run once it warmed up enough and it idled great, but if you gave it any more than half throttle it bogged down. It never actually died but it stumbled and ran rough. Pulling the choke at low speed/idle kills it but pulling it out while it’s bogging picks it back up and it takes off. Assumption was dirty carbs from sitting and I had never rebuilt them in my time owning them. Ordered genuine Mikuni kits with needles and seats and cleaned and rebuilt the carbs. Pop off was at the low end of the range, but in range. 19 PSI is all I could get using the springs that were in the carbs already.
Go to test run it today and same thing happens. Won’t run at full throttle without some choke and at 1/4 - 1/2 throttle it’ll pull back after 15 seconds of running or so. It does seem to hesitate if you mash the throttle from a standstill. Kind of rumbles along and then bam it goes. Also if you let it idle more than 20 seconds or so it starts idling real rough. Compression is good at 150/148 so no issue there. Any ideas of where to start looking here? Air leak in the fuel system when pulse pressure rises? Appreciate any advice!

 

[mikidymac]

Fuel selector is suspect since they are usually toast when cleaned.

19 psi is suspect since Mikuni shows even with the lowest spring 65 gram your 1.5 needle and seat should be at 32 psi.

 

[thomas0202]

Fuel selector is suspect since they are usually toast when cleaned.

19 psi is suspect since Mikuni shows even with the lowest spring 65 gram your 1.5 needle and seat should be at 32 psi.

If that's the case then it's likely that selector that's my issue then. When the ski was stored it had no issues running and that was with old fuel lines. The selector is the only thing that's really been pulled apart other than the carbs, which passed all the pressure tests. I think tomorrow I'll just plumb in a lawn mower shutoff and see if that fixes my problem while one is on order. I was thinking either the selector or the water separator o-ring so I'm glad I was on the right track.

As for the pop off pressure, I was going by what seadoo source has listed for the 95 GTX. It said 19 - 35 so that's why I went with it. The carbs had definitely been gone through before since I found some stripped screw heads on the metering plate, so there's a chance it has the wrong springs. Given that they popped off at 19 before and after rebuilding and it ran so good before I thought nothing of it... Would you recommend ordering some new 65 gram springs and testing again? If that will make the ski run even better I'll definitely get that done.

 

[JeremyD615]

There’s no need to plumb in a temporary shut off. You can just bypass the selector temporarily to verify that the problem is fixed. Just run your reserve line into the water separator and plug the “on” nipple.

 

[thomas0202]

Got it running right today. The oring on the fuel filter bowl was torn. Local dealer had the whole assembly for 22 bucks so I just replaced it all. Also bypassed the selector valve just for good measure. Took it out on the water and it runs fantastic. Got a selector valve coming and then I should be ready to ride this summer

 

[JeremyD615]

Nice! I’m glad you found the solution!