Mercury 25 EFI Service Manual page 292

Cylinder Head
4. Rotate the camshaft so the number one timing mark on the camshaft gear is aligned with the timing mark on the cylinder
head.
a
Description
Camshaft gear bolt
5. Ensure the cylinder head and cylinder block mating surface is clear of debris.
6. Install a new cylinder head gasket.
7. Install the cylinder head onto the cylinder block.
8. Apply a small amount of 10W‑30 4‑Stroke Marine Engine Oil to the cylinder head bolt threads. Tighten the cylinder head
bolts and the perimeter bolts in two steps in the sequence shown to the specified torque.
Tube Ref No.
10W-30 4-Stroke Marine
110
Engine Oil
Description
Cylinder Head Bolts (M8 x 60) (8)
Perimeter Bolts (M6 x 53) (3)
9. Install a new seal on the cylinder head cover.
10. Install the cylinder head cover onto the cylinder head. Secure the cylinder head cover with eight bolts. Tighten the cylinder
head cover bolts in two steps to the specified torque.
Page 4B-20
b
20968
5
1
4
8
Description
© 2016 Mercury Marine
a - Cylinder head timing mark
b - Camshaft gear timing mark
6
10
2
9
3
11
7
Where Used
Cylinder head bolt threads
First Torque
Final Torque
First Torque
Final Torque
Nm lb. in.
11 97
11790
Part No.
92-8M0078625
Nm lb. in.
10 88.5
30
6 53
10 88.5
90-8M0105568 eng MARCH 2016
lb. ft.
lb. ft.
22