1990 Seadoo Sp carb

[ORANGEFLY]

My 90 sp has had some changes before I got it and it hasnt ran right so I have been troubleshooting and I am kinda lost now. First off it has 137 psi compression in both cylinders. it has a sbn carb on it that has been rebuilt. It will start and run it just doesnt plain for a long time. When I get it started it will idle somewhat smooth at 4500 rpm the same as my 93. It will sometimes spit/sputter and white smoke comes out somewhere around the carb havent been able to pinpoint it. At full throttle it will only reach 8300 rpm where the 93 is alot higher then that my tach wont go that high. It is getting good fire could it be that its out of time? Or the wrong jets and getting to much fuel or not enough? I have spent hours on it and this is where Im stuck. Where do I go next? Any suggestions would be appreciated. I do know the guy that had it has been to the rotary valve he gave me a book on it and inside I found the paper diagram for the rotary valve.:boxing_smiley::willy_nilly::banghead::cuss:

 

[Dr Honda]

Something is very wrong.

First... your idle in the water should be around 1500 RPM, and your red-line for both of these engines is only 6500 rpm. If it's reving above 8000... it's going blow up.

It sounds like someone has removed the rev limiters. That is not a good idea if you want the engines to live for more than a few trips out.


The planing issue is either your pump is out of spec... or most likely... your drive shaft seal is shot... and it's sucking air.

 

[ORANGEFLY]

The tach that I borrowed may be off he used it on lawn mowers and its digital I will pick up another tach. I know the guy I got it from had been into the prop stuff and redone some pump things. What do you think the spit thing is that going on inside the hull? I'm goin to pull the carb back off and remove the intake because he had been into the rotary valve and he like to leave gaskets off for some reason. So that could be part of it also. I hate backtracking to find what people have done why not just leave things alone but I have been redoing his mess for months now.