1st test drive on GSX Limited

[Spades]

Bought the ski in non-running condition, would run when injecting fuel in the spark plug holes so i was comfortable with purchasing still. I went through the carbs, jets, all passages, internal filters, needle & seats, diaphragms, fuel pump, and changed out all the gray Tempo fuel lines, bypassed the fuel selector (for now), brand new fuel filter.... Fired it up and idled fine, but when snapping the throttle (sitting on the trailer) it would bog, so i pulled the carbs again and found the accelerator pump to not be injecting, had a torn orange internal diaphragm so i decided to eliminate the accelerator pump and rejet to 95 lows and 165 highs (has R&D Power Plenum), reassembled it and sounded fine on the trailer. So yesterday took to the lake and the bogging is back! Even after putting back on the trailer same bog exists as prior to rejetting. The way im thinking its happening is the needle & seat is lazy to pop off. I can give up to 1/3 throttle before it bogs, but if i hold it at 1/3 for about 5 seconds the engine tone will change and i can now throttle up to 2/3 (any more and it will bog again) and hold it there for another 5 seconds until i feel the ski start to accelerate more on its own (RAVE kicking in?) and at that point i can now give it full throttle. This is repeatable every single time. After couple hours i started to get comfortable holding WOT for longer periods, and at one point went for about almost a minute and runs perfect until i decelerate and close the throttle, then the bogging happens all over again. Am i right on thinking sticking needle & seat? I read that after 1/3 throttle the needle & seat doesnt really come into play anymore, so im doubting it because the bogging happens again at 2/3 throttle




Only other issue i have is it porpoises even on near perfect flat water, the scoop grate and ride plate are all intact and nothing seems to be out of place in that area.

[toxicgun]

Bought the ski in non-running condition, would run when injecting fuel in the spark plug holes so i was comfortable with purchasing still. I went through the carbs, jets, all passages, internal filters, needle & seats, diaphragms, fuel pump, and changed out all the gray Tempo fuel lines, bypassed the fuel selector (for now), brand new fuel filter.... Fired it up and idled fine, but when snapping the throttle (sitting on the trailer) it would bog, so i pulled the carbs again and found the accelerator pump to not be injecting, had a torn orange internal diaphragm so i decided to rejet it to 95 lows and 165 highs (has R&D Power Plenum), reassembled it and sounded fine on the trailer. So yesterday took to the lake and the bogging is back. The way im thinking its happening is the needle & seat is lazy to pop off. I can give up to 1/3 throttle before it bogs, but if i hold it at 1/3 for about 5 seconds the engine tone will change and i can now throttle up to 2/3 or it will bog, hold it there for another 5 seconds until i feel the ski start to accelerate more on its own and at that point i can now give it full throttle. This is repeatable every single time. After couple hours i started to get comfortable holding WOT for longer periods, and at one point went for about almost a minute and runs perfect until i decelerate and close the throttle, then the bogging happens all over again. Am i right on thinking sticking needle & seat? I read that after 1/3 throttle the needle & seat doesnt really come into play anymore, so im doubting it because the bogging happens again at 2/3 throttle




Only other issue i have is it porpoises even on near perfect flat water, the scoop grate and ride plate are all intact and nothing seems to be out of place in that area.

sounds like it isnt getting enough fuel. Mine did that when I was running too much oil for premix, went away when I dropped the ratio. Be careful revving the 951 on the trailer, it will run away. If it does run away pull the choke to kill the engine.

[Matt Braley]

You can try to fine tune it with the adjustment needles. If it's a lean bog you can open the needles up to 2 turns out from closed in 1/4 turn increments.

Trim down the steering nozzle to smooth the ride out.

[Spades]

The jetting recommendations for having flame arresters (95 pilot, 165 main, 95 gram spring) should put me pretty close, but i feel something else is wrong. The bog indicates lean mix but it chokes bad enough to believe that simply turning the mixture screw will not cure it. I guess ill have to tear into it again and see if there are any new clogs in the passages, or if indeed the needle & seat is sticking.

I am familiar with using the trim, the ski porpoises at all positions. And in near perfect glass water it shouldnt porpoise at ANY trim setting. A quick look under didnt reveal anything obvious, but I will get under it again in a few days (if it warms up) and analyze it more.

[Spades]

I switched over to an 80g spring and got a chance to take it out last memorial weekend. I was expecting it to correct the 1/3 throttle bog, but instead it corrected the 2/3 throttle bog. So 1 down, 1 more to go, slowly but surely making progress.