Nanni N4.40, Workshop Manual

Page: 144 / 175

ENGINE
03-M-E3B, 03-M-DI-E3B, 03-M-E3BG, WSM
1-S74
[3] SERVICING
(1) Cylinder Head and Valves
Top Clearance
1. Remove the cylinder head.
2. Move the piston up and attach a strip of fuse on the piston head
at 3 positions with grease.
3. Lower the piston and install the cylinder head. (Use a new
cylinder head gasket and tighten with a specified tightening
torque.)
4. Turn the flywheel until the piston goes more than the top dead
center.
5. Remove the cylinder head and measure the thickness of the
fuses.
6. If the measurement is out of the factory specifications, examine
the oil clearances between the crankpin and bearing. Also
examine that between the piston pin and bushing.
NOTE
• After you examine the top clearance, make sure that you
assemble the cylinder head with a new cylinder head
gasket.
M00000003ENS0105US1
Top clearance
Factory
spec.
D1503-M,
D1703-M,
D1803-M,
V2003-M,
V2203-M,
V2403-M,
V2403-M-T,
D1703-M-BG,
V2003-M-BG,
V2003-M-T-BG,
V2203-M-BG,
V2403-M-BG
0.575 to 0.675 mm
0.0227 to 0.0265 in.
D1803-M-DI,
V2403-M-DI,
V2403-M-DI-T
0.60 to 0.70 mm
0.024 to 0.027 in.
Tightening torque Cylinder head screws
93.2 to 98.0 N·m
9.50 to 10.0 kgf·m
68.8 to 72.3 lbf·ft
(1) Piston
(2) Fuse [A] D1503-M, D1703-M, D1803-M,
V2003-M, V2203-M, V2403-M,
V2403-M-T, D1703-M-BG,
V2003-M-BG, V2003-M-T-BG,
V2203-M-BG, V2403-M-BG
[B] D1803-M-DI, V2403-M-DI,
V2403-M-DI-T
KiSC issued 06, 2009 A