2006-2010 Suzuki DF150 / DF175 4-Stroke Outboards Service Manual, Page 274Get this manual
POWER UNIT
Cylinder bore Inspect cylinder walls for scratches, roughness, or ridges which indicate excessive wearIf cylinder bore is very rough, deeply scratched or ridged, bore cylinder and use oversize piston Cylinder bore wear (difference) Using telescoping gauge, measure cylinder bore in both axial (vertical line, following crankshaft) and transverse (horizontal line across crankshaft) directions at two positions as shown in figureNOTE: Purchase commercially available telescoping gauge for this measurement1Telescoping gauge
Check for followings: Difference between measurements at the two positions (taper) Difference between axial and transverse measurement (out-of-round)Cylinder bore wear (difference) Service limit: 0.10 mm (0.039 in) If measurement exceeds service limit, bore or replace cylinder