Cylinder Head Specifications - Mercury 25 EFI Service Manual

Cylinder Head

Cylinder Head Specifications

Maximum deck warp
Number of valves
Number of valves per cylinder
Number of cams
Camshaft bearing outside diameter
Pulley side
Pulley side (service limit)
Oil pump side
Oil pump side (service limit)
Cam lobe height
(25) Intake and exhaust
(25) Intake and exhaust (service limit)
(30) Intake and exhaust
(30) Intake and exhaust (service limit)
Valve lash
Intake
Exhaust
Valve seat angles
Valve spring free length
Valve spring free length (service limit)
Valve stem diameter
Intake
Intake (service limit)
Exhaust
Exhaust (service limit)
Valve face width (intake and exhaust)
Valve face width (service limit)
Valve seat width
Valve guide bore
Intake and exhaust
Intake valve guide bore (service limit)
Exhaust valve guide bore (service limit)
Valve stem to valve guide clearance
Intake
Intake (service limit)
Exhaust
Exhaust (service limit)
Rocker arm shaft outside diameter
Rocker arm shaft outside diameter (service limit)
Rocker arm inside diameter
Rocker arm inside diameter (service limit)
Rocker arm shaft clearance
Cylinder head upper camshaft bearing inside diameter
Oil pump camshaft bearing inside diameter
Valve stem seal color
Intake
Exhaust
Page 4B-2
Cylinder Head Specification
© 2016 Mercury Marine
0.1 mm (0.004 in.)
6
2
1
17.98 mm (0.708 in.)
17.95 mm (0.707 in.)
15.97 mm (0.629 in.)
15.95 mm (0.628 in.)
23.87 mm (0.9398 in.)
23.60 mm (0.9291 in.)
24.28 mm (0.9559 in.)
24.0 mm (0.9449 in.)
0.13–0.17 mm (0.005–0.007 in.)
0.18–0.22 mm (0.007–0.008 in.)
30°, 45°, 60°
35 mm (1.38 in.)
33.5 mm (1.319 in.)
5.48 mm (0.216 in.)
5.46 mm (0.215 in.)
5.46 mm (0.215 in.)
5.44 mm (0.214 in.)
1.0 mm (0.04 in.)
2.0 mm (0.08 in.)
1.0 mm (0.04 in.)
5.51 mm (0.217 in.)
5.55 mm (0.218 in.)
5.57 mm (0.219 in.)
0.008–0.04 mm (0.0003–0.0016 in.)
0.007 mm (0.0028 in.)
0.025–0.057 mm (0.001–0.0022 in.)
0.1 mm (0.004 in.)
12.99 mm (0.511 in.)
12.94 mm (0.509 in.)
13.01 mm (0.512 in.)
13.05 mm (0.514 in.)
0.006–0.035 mm (0.0003–0.0014 in.)
18.01–18.025 mm (0.709–0.710 in.)
18.01–18.025 mm (0.709–0.710 in.)
Black
Green
90-8M0105568 eng MARCH 2016