Bombardier SeaDoo 2000 factory shop manual volume 2, Page 53Get this manual
Section 03 TROUBLESHOOTING Subsection 01 (TROUBLESHOOTING CHART)
ENGINE CONTINUALLY BACKFIRES
OTHER OBSERVATION Weak spark Spark plugs Ignition timingTDC setting Carburetor (if so equipped) Engine POSSIBLE CAUSE Fouled, defective spark plugs (carburetor models) Malfunction of rev limiter in MPEM (carburetor models) Spark plug leads or wiring reversed Incorrect setting Sheared flywheel key Carburetion too lean Intake leakcrankshaft seal failure (carburetor models) REMEDY Cleanreplace Cleanreplace, refer to section ELECTRICAL SYSTEM Check with wiring diagram Checkreset, refer to section ELECTRICAL SYSTEM Checkreplace, refer to sections ELECTRICAL SYSTEM and ENGINE Checkadjust, refer to section FUEL SYSTEM Pressure check engine, refer to section ENGINE