High speed Idle 96 SPX

[bchtown]

I recently purchased a pair of 1996 SPX Sea Doos. I finally got them into the water and found that one had no power beyond idle. When I got them out of the water I found that the fuel line that apparently is the return line that Y's off of the carbs and returns back to the fuel tank had come off of the fitting at the fuel tank. I replaced it and when I started it again it now is Idling way to fast but does seem to have the upper end power that it was lacking prior to reinstalling the fuel line at the tank.
I am really out of my element with 2 strokes, could someone give me their opinion on this issue.
Thanks,
Bchtown

 

[JPX]

That surprises me a little that you didn't fill up your hull with fuel on the return side.

But it doesn't surprise me that you had problems with how the boat ran - without sufficient pressure building in the fuel loop, the carbs can't suck in fuel on the other side efficiently.

Loose fuel hose connections create the same problem above along with check valves that are not working correctly (no flow one way, flow the other).

If the fuel system was already a bit 'weak', then previous owner/mechanic may have tried fiddling with the fuel mixture (low speed and high speed adjusters) and the idle adjuster.

You should make sure the low/high speed adjusters are set correctly THEN set the idle speed with the idle screw.

Use the photo below to locate the adjusters. Close the high speed screws clockwise closed. Close the LOW speed screws clockwise, THEN open them 1 and 1/4 turn counterclockwise. Then set your idle speed screw (a timing light with a tach helps to determine RPMs if you don't have a dash tach).