800 Rossier pipe help

[DThitoff]

I have a 96 XP 800 I put a Rossier pipe,Solas xo prop and Prok flame arresters on. It will start right up on the trailer but once in the water I can get it start once or twice then it just cranks. Carbs are 75 lows, 145 highs, 2.0 needle and seat, 22 and 25 pop off. Compression I have 120 in the rear and 130 in the front with an innova tester. Any help would be appreciated. Thanks in advance

 

[DThitoff]

I got the ski to run just doesn’t like being at an incline on the ramp. Whenever I give it any throttle it just hesitates no matter how I open the lows. Not sure if I need bigger jets?

 

[mikidymac]

First off you are on borrowed time with that engine. At 120 psi the engine is done and typically will have a hard time starting in the water. Also with 10 psi difference between cylinders you have a mechanical issue like the low cylinder seizing.
Putting a pipe on a low compression engine is about the worst thing you can do.

 

[Keno]

I agree that the best course of action is to rebuild the top end. Have your read the Mikuni SBN tuning guide? https://www.mikuni.com/pdf/sbn_manual.pdf You'll want to back the ski into the water, set a high idle to get it started, then adjust the idle with the low speed screws and idle adjustment screw to obtain a smooth idle around 1500rpm.

 

[DThitoff]

Thanks for the info

 

[mandriva]

Thanks for the info

yes , rebuild the top end, but you need repicht your prop 1 degré less or put solas X
i got 7100/7150 rpm with solas xo
and solas X i got 7250/7280 rpm

 

[DThitoff]

yes , rebuild the top end, but you need repicht your prop 1 degré less or put solas X
i got 7100/7150 rpm with solas xo
and solas X i got 7250/7280 rpm

Thank you I’ll give that a try