Valve Timing Diagram - Weifang 495 Operation And Maintenance Manual

'\
.
der to keep the valve timing as required, the valve lashes should be
adjusted to the prescribed valve.
'Intake valve Opens
Direction of Rotation
Intake valve Close
,1
"
i
,
I ---
\
Exhaust valve closes
Exhaust valve opens
Fig. 5 Valve timing Diagram
2). Maintenance
of
Cylinder Head
and
Valve Gear
(l)Adjusting Val.ve Lash
Adjusting method: Turning the flywheel to let the piston of
the first cylinder moving up to the top dead centre in its compres-
sion stroke. (When the top dead centre mark "0" on the flywheel
in aligned with the line marked at the side of the opening on the
flywheel housing ,the pistons of the fJrstand fourth cylinders are
at their top dead centre positions. If the exhaust valve of th.e sec-
ond cylinder opens, the' piston of the first cylinder is in the mean-
time Just
a~I~.top
dead centre in its compression stroke.) Loosen the
~
,
locking nuts of adjusting screws on the rocker arms of both th.e in-
take and exhaust valves on the first cylinder of the intake valve on
the second cylinder and of the exhaust valve on the third cylinder,
26