2009-2010 Suzuki DF70A DF80A DF90A Outboard Service Manual, Page 150Get this manual
1D-39 Power Unit Mechanical: Valve seat servicing If valve seat contact width is out of specification, reface valve seat as follows: Valve seat angle Intake side: 304560 Exhaust side: 1545 INEX
If width "a" is too high (or wide), reface valve seat using small angle cutter (Intake side: 30Exhaust side: 15If width "a" is too low (or narrow), reface valve seat using 60 angle cutter (Intake side) If width "a" is too low (or narrow), reface valve seat using 45 angle cutter (Exhaust side)
60 45 30 15
I9J011140046-02
To reface valve seat, use the following valve seat cutting tool Valve seat cutter 45 (Neway 122) Valve seat cutter 30 (Neway 126) Valve seat cutter 15 (Neway 120) Valve seat cutter 60 (Neway 111) Solid pilot (Neway, N-100-5.52) (09916-24450) Handle (Neway, N-505) (09916-54910) NOTE Turn cutter clockwise, never counterclockwise1) Remove all carbon from valve and valve seat2) Using 45 angle cutter, reface valve seat3) Check valve seat contact width "a"Refer to "Valve seat contact width" (Page 1D-38)Too high (wide)