Valve Timing - Kubota Z400-B Handbuch

[81 INLET AND EXHAUST VALVES
The valve and its guide for the inlet are different from those
for the exhaust.
Other parts, such as the spring (6), spring retainer (5), collet
(4) , stem seal (2) and cap
(1)
are the same for both the inlet
and exhaust.
(1 )
Cap
(2) Stem Seal
(3) Valve Guide
(4) Collet
(5) Spring Retainer
(6)
Spring
(7) Inlet Valve
(8) Exhaust Valve
@
O107F021
[9] VALVE TIMING
The timing for opening and closing the valve is extremely
important to achieve effective air intake and sufficient gas
exhaust.
The appropriate tim ing can be obtained by aligniny the marks
on the crank gear and the cam gear when assembling.
Inlet valve open
CD
0.35 rad. (20°) before T.O.C.
Inlet valve close
~
0.79 rad. (45°) after B.O.C.
Exhaust valve open
@
0.87 rad. (50°) before B.O.C.
Exhaust valve close
®
0.26 rad. (15°)after T.O.C.
O109F()23
[10] FLYWHEEL
The flywheel is installed on the rear end of the crankshaft
and its inertia tends to keep it turning at a constant speed,
while the crankshaft tries to speed up during the power stroke
and slow down during other strokes.
The flywheel has gear teeth around its outer rim, which mesh
with the drive pinion of the starter.
The flywheel also has marks on its outer rim. Each must be
aligned with the mark on the rear end plate to get the top
dead centers and the injection timings.
M-9