11-49
Inspection
Piston Ring
(1)
Check whether the piston ring has damage, over abrasion
or breakage, if it has, change it, in the case of changing the
piston, the piston ring needs to be changed too.
(2)
Check the clearance between the piston ring and the piston
ring groove, if it is over large, change the piston ring or the
both parts.
Standard value: 0.02
0.06mm
Limit value: 0.1mm
(3)
Put the piston ring in the cylinder and locate it with the
crown face of the piston, then measure the opening clear-
ance with the feeler. If the opening clearance is over large,
change the piston ring.
Standard value:
First ring
0.25
0.35mm
Second ring
0.40
0.55mm
Oil ring
0.10
0.40mm
Limit value:
First and second ring
0.8mm
Oil ring
1.0mm
Play of Crank Pin (clearance gauge of plastic cord)
(1)
Clear away the oil on the journal and bearing of the
connecting rod thoroughly.
(2)
Cut the clearance gauge of plastic cord in the length that is
the same with the bearing width, and then put them on the
crank handle and parallel them with the axial center line.
(3)
Mount on the connecting rod cap carefully and tighten the
nut as per the specified torque.
(4)
Dismantle the connecting rod cap carefully.
(5)
Measure the max width of the flattened plastic cord with
the gauging ruler printed on the package bag of the clear-
ance gauge of plastic cord, thus obtaining the clearance
value.
Standard value: 0.02
0.05mm
Limit value: 0.1mm
5EN0066
press it in with piston
priston ring
opening clearance
5EN0548
1EN0246
clearance gauge of plastic cord
1EN0271
ENGINE
CYLINDER HEAD AND VALVE
