Valve Adjustments - Mercury 25 EFI Service Manual

11. Install the fuel pump. Torque the fuel pump retaining screws to specification. Refer to Section 3C ‑ Service Procedures
for fuel pump hose connection.
b
a
Description
Cylinder head cover bolts (M6 x 53) (8)
Fuel pump retaining bolts
12. Install the oil pump. Refer to Section 4C ‑ Oil Pump.

Valve Adjustments

IMPORTANT: The timing belt and gears must be installed in the correct position or valve damage may occur.
1. Remove the flywheel cover and timing belt cover. Refer to Section 8A–Recoil Starter.
2. Disconnect the inlet and outlet fuel hoses on the fuel pump.
3. Remove the cylinder head cover.
4. Remove the spark plugs.
5. Measure the valve lash clearance with a feeler gauge. Adjust the valve lash if out of specification.
NOTE: When loosening locknuts, hold the adjusting screw with a square drive socket or crescent wrench to prevent it from
moving.
a
b
Valve Clearance (Cold)
Intake
Exhaust
6. Perform the following adjustment steps if the valve lash is out of specification:
a. Turn the flywheel to align the camshaft gear timing mark with the timing mark on the cylinder block.
b. Adjust the intake and exhaust valve clearance for cylinder #1.
c. Turn the flywheel 240° and align the second mark (II) on the camshaft gear with the timing mark on the cylinder block.
d. Adjust the intake and exhaust valve clearance for cylinder #2.
e. Turn the flywheel 240° and align the third mark (III) on the camshaft gear with the timing mark on the cylinder block.
f. Adjust the intake and exhaust valve clearance for cylinder #3.
90-8M0105568 eng MARCH 2016
a - Cylinder cover cover bolts (8)
b - Fuel pump retaining bolts (2)
a
11485
a -
b -
11809
Nut driver with square drive socket
Wrench
0.13–0.177 mm (0.005–0.007 in.)
0.177–0.228 mm (0.007–0.009 in.)
© 2016 Mercury Marine
Cylinder Head
Nm lb. in. lb. ft.
6 53
9 80
5.4 48
Page 4B-21