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Inspecting the wrist pin
- Measure the outer diameter of the gudgeon pin.
Characteristic
Standard diameter gudgeon pin
13 -0-0.004mm
Minimum admissible diameter pin
12.990 mm
Inspecting the piston
- Calculate the piston pin coupling clearance.
Fitting clearance
Pin coupling clearance
13 +0.010+0.005mm
0.005 ÷
0.014 mm
- Measure the outside diameter of the piston, perpendicular to the gudgeon pin axis.
- Carry out the measurement at 27 from the piston crown as shown in the figure.
- Carefully clean the sealing rings housings with the aid of an old piston ring.
- Measure the coupling clearance between the sealing rings and the piston grooves using a thickness
gauge, as shown in the figure.
- If the clearances detected exceed the limits specified in the table, the piston and the piston rings should
be replaced.
PISTON
Name
Description
Dimensions
Initials
Quantity
Top piston ring
0.030 ÷ 0.065 mm
0.080 mm
Middle piston ring
0.020 ÷ 0.055 mm
0.070 mm
oil scraper
0.040 ÷ 0.160 mm
0.20 mm
ET4 50
Engine
ENG - 83
Summary of Contents for ET4 50
Page 1: ...WORKSHOP MANUAL 633367 ET4 50 ...
Page 4: ......
Page 6: ...INDEX OF TOPICS CHARACTERISTICS CHAR ...
Page 16: ...INDEX OF TOPICS TOOLING TOOL ...
Page 24: ...INDEX OF TOPICS MAINTENANCE MAIN ...
Page 33: ...494929Y Exhaust fumes analyser 020331Y Digital multimeter ET4 50 Maintenance MAIN 33 ...
Page 34: ...INDEX OF TOPICS TROUBLESHOOTING TROUBL ...
Page 40: ...INDEX OF TOPICS ELECTRICAL SYSTEM ELE SYS ...
Page 56: ...INDEX OF TOPICS ENGINE FROM VEHICLE ENG VE ...
Page 58: ...INDEX OF TOPICS ENGINE ENG ...
Page 120: ...INDEX OF TOPICS SUSPENSIONS SUSP ...
Page 130: ...INDEX OF TOPICS BRAKING SYSTEM BRAK SYS ...
Page 136: ...INDEX OF TOPICS CHASSIS CHAS ...
Page 144: ...INDEX OF TOPICS PRE DELIVERY PRE DE ...
Page 148: ...INDEX OF TOPICS TIME TIME ...