Mercury Mariner Outboard 225 3 Litre Service Manual 1994, Page 65Get this manual
TimingSynchronizing Adjusting SPECIFICATIONS MODEL 225 FULL THROTTLE RPM RANGE 50005500
Engine could start when turning flywheel to check timing pointer adjustmentRemove all spark plugs from engine to prevent engine from starting
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Description
IDLE RPM (IN FORWARD 600700 GEAR) MAXIMUM TIMINGWIDEOPEN THROTTLE (5500 RPM) IDLE TIMING SPARK PLUG FIRING ORDER 22' BTDC (ECU821717)