Inspecting the piston
- Carefully clean the seal housings.
- Measure the coupling clearance between the
seal rings and the grooves using suitable sensors,
as shown in the diagram.
- If the clearance is greater than that indicated in
the table, replace the piston.
Inspecting the piston rings
- Alternately insert the three sealing rings into the cylinder, in the area where it retains its original di-
ameter. Using the piston, insert the rings perpendicularly to the cylinder axis.
- Measure the opening (see figure) of the sealing rings using a feeler gauge.
- If any measurements are greater than specified, replace the piston rings.
N.B.
BEFORE REPLACING ONLY THE PISTON RINGS, ENSURE THAT THE CLEARANCE BETWEEN
THE PISTON RINGS AND THE PISTON RING GROOVES, AND BETWEEN THE PISTON AND THE
CYLINDER, IS AS SPECIFIED. IN ANY CASE, NEW PISTON RINGS USED IN COMBINATION WITH
A USED CYLINDER MAY HAVE DIFFERENT BEDDING CONDITIONS THAN THE STANDARD.
Removing the piston
- Install piston and wrist pin onto the connecting rod, aligning the piston arrow the arrow facing towards
the exhaust.
- Fit the pin stop ring onto the appropriate tool.
- With opening in the position indicated on the tool
S = left
Vespa GTV 125
Engine
ENG - 35
Summary of Contents for GTV 125
Page 4: ......
Page 6: ......
Page 7: ...INDEX OF TOPICS CHARACTERISTICS CHAR ...
Page 20: ...Characteristics Vespa GTV 125 CHAR 14 ...
Page 21: ...INDEX OF TOPICS TOOLING TOOL ...
Page 34: ...Tooling Vespa GTV 125 TOOL 14 ...
Page 35: ...INDEX OF TOPICS MAINTENANCE MAIN ...
Page 57: ...INDEX OF TOPICS TROUBLESHOOTING TROUBL ...
Page 64: ...Troubleshooting Vespa GTV 125 TROUBL 8 ...
Page 65: ...INDEX OF TOPICS ELECTRICAL SYSTEM ELE SYS ...
Page 89: ... Refit the battery cover Vespa GTV 125 Electrical system ELE SYS 25 ...
Page 90: ...Electrical system Vespa GTV 125 ELE SYS 26 ...
Page 91: ...INDEX OF TOPICS ENGINE FROM VEHICLE ENG VE ...
Page 98: ...Engine from vehicle Vespa GTV 125 ENG VE 8 ...
Page 99: ...INDEX OF TOPICS ENGINE ENG ...
Page 156: ...Engine Vespa GTV 125 ENG 58 ...
Page 167: ... Remove the maximum nozzle Remove diffuser Vespa GTV 125 Engine ENG 69 ...
Page 177: ...INDEX OF TOPICS SUSPENSIONS SUSP ...
Page 199: ...INDEX OF TOPICS BRAKING SYSTEM BRAK SYS ...
Page 215: ...INDEX OF TOPICS COOLING SYSTEM COOL SYS ...
Page 221: ...INDEX OF TOPICS CHASSIS CHAS ...
Page 237: ...INDEX OF TOPICS PRE DELIVERY PRE DE ...
Page 241: ...INDEX OF TOPICS TIME TIME ...