Mercury Mariner 25HP 4-Stroke Outboard Service Manual 1997, Page 136Get this manual
Camshaft 1Inspect the camshaft for pittingheat discolor
3Measure the camshaft bore diameters (a) and camshaft bearing diameters (b and c)55783
atien, scratches and for the following measurementsReplace camshaft if worn or not within specification2Measure the cam lobe length (a) and width (b)55805
Cam Lobe Specifications
Intake .2161.220 in(30 .8930 .99 mm) 1.213 -1 .217in(30.8230.92 mm) 1.0221.025 in(25.95 -26.05 mm) 1.0221.025 in(25.95 -26.05 mm)