Cylinder/Piston - DAELIM S2-250 Service Manual

11. CYLINDER / PISTON
SERVICE INFORMATION· · · · · · 11-1
TROUBLESHOOTING · · · · · · · · · · 11-1
CYLINDER REMOVAL· · · · · · · · · · 11-2
PISTON REMOVAL· · · · · · · · · · · · 11-2
SERVICE INFORMATION
GENERAL SAFETY
● Be careful not to damage the mating surfaces by using a screwdriver when disassembling the cylinder. Do not strike the
cylinder too hard during disassembly, even with a rubber or plastic mallet, to prevent the possibility of damage to the
cylinder fins.
● Take care not to damage the cylinder wall and piston.
● Check parts after disassembling, and clean and dry with an air hose prior to taking measurements.
SPECIFICATIONS
ITEM
I.D.
WARPAGE
CYLINDER
CYLINDRICITY
TRUE ROUNDNESS
RING-TO-GROOVE TOP
CLEARANCE
PISTON,
RING END GAP
PISTON RING
PISTON O.D.
PISTON-TO-CYLINDER CLEARANCE
PISTON PIN HOLE I.D
PISTON PIN O.D
PISTON-TO-PISTON PIN CLEARANCE
CONNECTING ROD SMALL END I.D. BORE
TROUBLESHOOTING
● When hard starting or poor performance at low speed occurs, check the crankcase breather for white smoke. If white
smoke is found, it means that the piston rings are worn, stuck or broken.
Comperssion too low or uneven compression
● Worn or damaged cylinder and piston ring
● Worn, stuck or broken piston rings
Comperssion too high
● Excessive carbon build-up in combustion
●
chamber or on piston head
STANDARD (mm)
72.705~72.715
SECOND
TOP
SECOND
OIL RING
17.002~17.008
16.994~17.000
17.016~17.034
PISTON RING INSTALLATION· · 11-5
PISTON INSTALLATION· · · · · · · · 11-6
CYLINDER INSTALLATION· · · · 11-6
0.01
0.01
0.01
0.2
0.015~0.050
0.1~0.25
0.15~0.30
0.25~0.7
72.67~72.69
0.010~0.040
0.002~0.014
Excessive smoke from exhaust muffler
● Worn or damaged piston rings
● Worn or damaged cylinder and piston
Abnormal noise piston
● Worn cylinder, piston and piston rings
● Worn piston pin hole and piston pin
● Incorrectly installed piston
SERVICE LIMIT (mm)
72.80
0.05
0.05
0.05
0.09
0.09
0.50
0.50
-
72.6
0.01
17.04
16.96
0.02
17.06
11-1
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