Mercury 40 Service Manual page 224

CYLINDER HEAD
Camshaft
1. Inspect the camshaft for pitting, heat discoloration, scratches and for the following mea-
surements. Replace camshaft if worn or not within specification.
2. Measure the cam lobe length (a) and width (b).
a
b
3. Measure the camshaft bore diameters (a) and camshaft bearing diameters (b and c).
c c
Page 4A-28
a
Cam Lobe Specifications
Intake
Exhaust
Intake
Exhaust
c
b
Camshaft Bore Inside Diameter "a"
1.4567 - 1.4577 in. (37.000 - 37.025 mm)
Camshaft Bearing Diameter "b"
1.4541 - 1.4549 in. (36.935 - 36.955 mm)
Camshaft Bearing Diameter "c"
1.4537 - 1.4545 in. (36.925 - 36.945 mm)
b
55805
1.216 - 1.220 in.
(30.89 - 30.99 mm)
1.213 - 1.217 in.
(30.82 - 30.92 mm)
1.022 - 1.025 in.
(25.95 -26.05 mm)
1.022 - 1.025 in.
(25.95 -26.05 mm)
a
a
90-828631R3 MARCH 1999
a a