ZONGSHEN ZS125-86 Service Manual page 73

1.4
Yes
[1]Check whether the gas no. is correct or has
stored for a long time.
[2]Check whether engine always runs with the
high speed or with loads.
[1]Check whether CDI device has problems.
[2]Check whether the flywheel of generator and
triggering coil are loose.
Spark plug dielectric is dark black.Exhaust
muffler emits black smoke when engine
runs with the medium/low speed.The
accelerating performance is bad and idle
speed is unstable.But it is normal when
with high speed.
Combustible mixed
gas is thick.
[1]Check whether air cleaner is blocked.
[2]Check whether the starting device of
carburetor(thickening system) is in good
working condition.
[3]Check whether the float level of
carburetor is too low.
Analysis of engine overheating
Engine overheats.
C h e c k w h e t h e r t h e
operation is correct.
Check whether there is sand or
smeary deposit on radiator.
No
Check whether the engine
ignition is timing.
No
Dismantle piston and check the
color of piston dielectric.Estimate the
mixed ratio of mixed gas according to
all kinds of exceptional phenomena.
s p a r k p l u g
dielectric is brown.
The ratio of Combustible
mixed gas is normal.
Check
C h e c k w h e t h e r
lubricating
c y l i n d e r e x h a u s t
system.
por t and exhaust
muffler are blocked
w i t h c a r b o n
deposite.
[1]Check whether the oil volume in crankcase is
insufficient.
[2]Check whether the oil in crankcase is dirty
or its mucosity is too bad.
[3]Check whether oil cleaner is blocked.
[4]Check whether oil pump is in good working
condition.
[5]Check whether lubricating way is blocked.
No
Check cooling
system.
a i r c o o l i n g
engine
Yes
Clean
Yes
C h e c k w h e t h e r
clutch slips.
Yes
No
Clutch slides.
Refer to 1.9.
spark plug dielectric is white.
When accelerating,engine has
intermission.The air flows back to
carburetor and engine power is
insufficient.
Combustible mixed
gas is too thin.
[1]Check whether fuel switch
is in good working condition.
[2]Check whether the float
level is too high.
[3]Check whether the holes on
carburetor are blocked.
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