Suzuki DF200/DF225/DF250 V6 4-Stroke Outboards Service Manual, Page 251Get this manual
POWER UNIT
09900-20101: Vernier calipers Valve seat contact width Standard: IN EX1.1 1.3 mm (0.0433 0.0512 in) If measurement exceeds specification, repair valve seatNOTE: For valve seat repair, see "Valve seat servicing" section on page 6-69VALVE SEAT SERVICING If valve seat contact width is out of specification, reface valve seat as follows: Valve seat angle Intake side15, 45, 60 Exhaust side15, 45, 60Valve seat cutter (NEWAY634) 45Valve seat cutter (NEWAY217) 15 09916-22420: Valve seat cutter (NEWAY114) 60 09916-24450: Solid pilot (NEWAYN-100-5.52) 09916-54910: Handle (N-505) NOTE: Turn cutter clockwise, never counterclockwise(1) Remove all carbon from valve and valve seat(2) Using 45 angle cutter, reface valve seat(3) Check valve seat contact width ASee the "Valve seat contact width" section on page 6-68(4) If width is too high (or wide), reface valve seat using 15 angle cutter If width is too low (or narrow), reface valve seat using 60 angle cutter(5) Clean up any burrs using 45 angle cutter very lightly Too low (narrow) Too high (wide)