Operation Manual

Inspecting the small end
- Measure the internal diameter of the small end
using an internal micrometer.
N.B.
REPLACE THE CRANKSHAFT IF THE DIAME-
TER OF THE ROD SMALL END EXCEEDS THE
STANDARD DIAMETER OR IT SHOWS SIGNS
OF WEAR OR OVERHEATING.
Characteristic
Checking the connecting rod small end: Maxi-
mum diameter
15.030 mm
Checking the connecting rod small end: Stand-
ard diameter
15 +0.015+0.025 mm
Inspecting the wrist pin
- Measure the outer diameter of the gudgeon pin.
- Calculate the coupling clearance between pin
and connecting rod end.
Characteristic
Pin diameter: Standard clearance
0.015 ÷ 0.029 mm
Pin diameter Standard diameter
14.996 - 15.000 mm
MP3 250 i.e. Engine
ENG - 33