Cylinder Block And Piston; Service Data - KEEWAY RKV125 Instruction And Maintenance Manual

XIII Cylinder Block and Piston
Preparatory data------------ 13.1
Fault diagnosis--------------13.2
Cylinder block-------------- 13.3

13.1 Service Data

Precautions on Operation
All the components shall be cleaned before inspection and test, and purged with high-pressure air.
Function of cylinder block: Cylinder block provides the space for gas compression, combustion
and expansion and guides piston movement. It also transfers part of heat in the cylinder to
surrounding coolant.
Function of piston:
Piston can bear the pressure generated by combustion of mixed combustible gas in the cylinder and transmit the
pressure to connecting rod to drive crankshaft to rotate.
It forms a combustion chamber with cylinder head.
It works as a slide valve to compress regularly fresh mixed gas from crankcase into cylinder and exhaust combustion
gas from the cylinder.
Basic data
ID
Cylindricity
Roundness
Flatness
Piston OD(measuring point)
Piston pin hole ID
Piston pin OD
Cylinder
Clearance between piston and piston pin
Clearance between piston ring and ring groove
Joint clearance of piston rings
Connecting rod small end ID
Clearance between linkage rod and piston pin
Item
Piston---------------------- 13.4
Cylinder installation----- 13.5
Standard Value
56.987-56.977
(8mm at the bottom of piston skirt)
14.002-14.008
13.994-13.997
0.005-0.014
Top ring 0.020-0.060
Second ring 0.020-0.060
Top ring
Second ring
Oil ring
14.010-14.018
0.013-0.024
Unit
Service Limit
57-57.01
0.005
0.004
0.02
0.25-0.35
0.20-0.35
0.20-0.70
: mm
57.10
0.05
0.05
0.05
56.93
14.04
13.96
0.05
14.06
0.10