2006-2010 Suzuki DF150 / DF175 4-Stroke Outboards Service Manual, Page 41Get this manual
PERIODIC MAINTENANCE
4Rotate top of cam 90 degree counterclockwise and remove shim from cut-away at tappet(Two tappets can be adjusted at the same timeDo not put your finger between camshaft and tappet while the tappet is being held with the tappet holder Use magnet to remove and install shim When installing shim, identification mark on the shim should face down (towards tappet)5After removing shim, measure thickness of original shim and determine correct thickness of shim for proper tappet clearance as calculated by following formula! 09900-20205: Micrometer INside:+ (C 0.25 mm) EXside:+ (C 0.32 mm) A: Correct thickness of shim for proper tappet clearance (mm) B: Thickness of original shim (mm) C: Original tappet clearance (mm) I.D No218 220 223 225 228 230 233 235 238 240 243 245