Weifang 495 Operation And Maintenance Manual page 24

1 ). Injection timing is too -early
(The rhythmic pounding noise
ca,n be heard clearly during the
engine running at idling).
2 ). Clearance between
piston
pin. and connecting rod sln.all
eIld bushing is too large (A
clear metallic
pou~nding
:noise
emits from the upper portion of
thecylindet 'when.engine-.:·r-uns
at
lo\v·speed:·'''or
when
:entgine
speed or s'uddenly drops to
the
idling) .
3 ) •
'Valve
pou·nd·s'
the piston
top~A
d.ull·cilcking
noi~e
emits
from joirlt surface of cylinder
and cylinder head, it will be
ev
7
en louder
if
the valve 'lash is
reduced." ' i'~
4 ). Connecting rod bearing or
main rearing
clearance:'~
is,-to'Q
large or
Olle
of these bearing. is
damaged.
(1~he
citll!,
pounding
noise em.its from the lower por-
tion of cylin(ler block).
5 ).
Valve
tash·es
~:'are
'toq·r·large
(The rtlythmic ciIcking noise
ca-nbe 'heard . clearly above: the
cylinder head).
Check and adjust thefuel1njec-
tion timing.
Replace the 'connecting:
rod
small end bushing.
Inspect,the.,~
valve;
lashes': ','and
'check the'valve
tim1fig.~·;
...
'
~
Replace the connecting rod
bearing or
,main)bea:ritig~,-~, "
103