2005 Yamaha F90TR 90HP Outboards Factory Service Manual, Page 106Get this manual
Cylinder block
Disassembling the cylinder block
1Place rag under the oil filter, and then remove the filter using the oil filter wrenchNOTE: Be sure to clean up any oil spills
Oil filter wrench: YU-38411 2Remove the crankcase bolts in the sequence shown, and then remove the crankcaseNOTE: Be sure to keep the bearings in the order as they were removed Mark each piston with an identification number of the corresponding cylinder Do not mix the connecting rods and capsKeep them organized in their proper groups
Checking the piston diameter