KEEWAY ATV250, Service And Maintenance Manual

Page: 43 / 97

39
E n g i n e c y l i n d e r c o m p r e s s i o n t e s t
The first step:
1.Start the engine ,so that the temperature
reaches to the temperature of going normally
；
2.Take down the spark plug, and connect the
manometer
；
3.Check following switches
：
(a) Fuel switch be in th position of “OFF”
；
(b) Ignition switch be in the position of
“OFF”
；
4.Air door in the state of “open
completely”,and start it for several times (6
－
8
times)
；
5.Write 13
±
1Kg/cm
2
。
The second step
： ： ： ：
When the pressure value of the air cylinder be smaller than 11Kg/cm
2
,we should install the spark plug , restart and
heat the engine ,and then pull down the spark plug ,drip several drops of engine oil to the firebox ,test again according to
the first step with the pressure gauge .
●
If the pressure of cylinder increased ,we should check :
a
．
Whether the cylinder have been abrased
；
b
．
Whether the piston or piston ring have been abrased ;
c
．
Whether the cylinder or piston has nick or have been blocked;
d
．
Whether the piston ring have been blocked in the slot of piston.
●
If the pressure of cylinder didn’t increase ,we should check
：
a
．
Whether the value of valve interval be correct or not ;
b
．
Whether the screw of cylinder cover have been twisted too tight or too loose ;
c
．
Whether the pedestal of valve have been abrased ;
d
．
Whether the valve have been bent.
e
．
Whether the timing of valve be correct or not ;
f
．
Whether the washer of cylinder head have been abrased .
The third step:
It requires that clean the carbon accumulated in the cylinder head
，
the piston and firebox of the engine when the
pressure of cylinder was more than 13Kg/cm
2
.