Yingang YG125-30B, Manual

Page: 59 / 151

YG125-30B Maintenance Manual Cylinder Head, Cylinder and Piston
63
Notice:
Do not drop the location pin into the crankcase.
Do not bruise the cylinder wall.
To mount the cylinder :
Installation is in the reverse order of removal. Precautions
for installation:
1. Confirm the location pin; clean all parts and
components, and check whether the cylinder oil
through is unobstructed, clean and free of leak
2. Replace a new cylinder gasket, and confirm the
notch direction of the piston ring; mount the cylinder
after fastening the piston with the piston slide gage
seat
Cylinder inspection
Check the cylinder for abrasion or damage, and check the
cylinder wall for scratch.
Check the cylinder wall for deformation, and use the edge
ruler and clearance gauge to inspect the planeness of the
cylinder
’
s joining surface.
Maintenance limit:
≤
0.05mm.
Measure the cylinder internal diameter. The measurement
shall be made at three positions: top, middle and bottom,
measure in two crossing directions for each position, and
finally calculate their mean value.
Maintenance limit:
≤φ
85.10mm
Work out the Cylinder
’
s grade slope.
Maintenance limit:
≤
0.05mm
Work out the Cylinder
’
s roundness.
Maintenance limit:
≤
0.05mm
Whether the cylinder wall is scratched
Clearance gauge
Edge ruler
Clearance gauge