Inspecting The Small End - Gilera 633721 Workshop Manual

Engine

Inspecting the small end

- Using a bore gauge, measure the connecting rod
small end diameter.
N.B.
IF THE CONNECTING ROD SMALL END DIAMETER EX-
CEEDS THE STANDARD DIAMETER, EXHIBITS WEAR OR
OVERHEATING, PROCEED TO REPLACE THE CRANK-
SHAFT AS DESCRIBED IN THE CRANKCASE AND
CRANKSHAFT CHAPTER.
Characteristic
Standard diameter:
22 + 0.025 +0.015 mm
Inspecting the wrist pin
- Check the pin outside diameter using a micrometer.
Characteristic
Standard diameter:
22 0 -0.004 mm
- Calculate the coupling clearance between pin
and connecting rod end.
Characteristic
Standard clearance:
0.015 ÷ 0.029 mm
- Measure the diameter of the bearings on the piston.
Characteristic
Standard diameter:
22 + 0.006 + 0.001 mm
- Calculate the piston pin coupling clearance.
N.B.
THE PIN HOUSINGS HAVE 2 LUBRICATION CHANNELS.
FOR THIS REASON, MEASUREMENT MUST BE MADE AC-
CORDING TO THE PISTON AXIS.
Characteristic
Standard clearance:
0.001 ÷ 0.010 mm
ENG - 140
Nexus 500 euro 3