Bombardier SeaDoo 2000 factory shop manual volume 1, Page 91Get this manual
Section 04 ENGINE Subsection 05 (TOP END)
GENERAL
The 2-stroke ROTAX engine rotates counterclockwise seen from the rear (PTO flywheel)The 717 and 787 RFI engines have rotary valve to control opening and closing of the intakeThe 947 engine uses reed valves in the crankcaseThe 787 RFI and 947 engines are also equipped with the RAVE system (Rotax Adjustable Variable Exhaust)CAUTION: No engine components can be interchanged between engines787 RFI and 947 Engines These engines are canted at 30 degree angle (they are not canted on the same side), lowering the center of gravity of the watercraftCylinder exhaust ports are located on the same side of the intake, allowing high volume tuned pipe design
787 RFI and 947 Engines On these engines, the RAVE valves are controlled by the Multi-Purpose Electronic Module (MPEM)To open the RAVE valves, the MPEM activates solenoid which directs the positive pressure from engine crankcase to the valves2 3