2002 Bombardier Quest 650XT Service Manual, Page 57Get this manual
Section 03 ENGINE Subsection 02 (TROUBLESHOOTING)
SYMPTOM CONDITION TestInspection
ENGINE TURNS OVER BUT FAILS TO STARTNORMAL USE1Check if single-spark ignition coil fits on spark plug (refer to ENGINE DOES NOT START-NO SPARK AT SPARK PLUG)2Check spark plugaDefine spark plug (no spark) or wrong spark plug gapReadjust gap and clean spark plug or replace3Check for fuel on spark plugaFlooded engine (spark plug wet when removed)Do not overchokeRemove wet spark plug, turn ignition switch to OFF and crank engine several timesInstall clean dry spark plugStart engine following usual starting procedure4Check engine compressionaInsufficient engine compressionReplace defective part(s) (expiston, ring(s), etc5At cold weather check engine decompressor (located on camshaft timing gear)aCentrifugal weight spring is not engaged andor damagedReadjust spring or replace centrifugal weight if damaged