Inspecting The Crankshaft Alignment - PIAGGIO MSS Fly 50 4T Workshop Manual

Engine
- Support the crankcase on a surface and place it
with the driving shaft axle in a vertical position.
- Warm the crankcase at ~ 120° C with a thermal
gun (and support).
- Fit the punch with guide and adaptor, place the
bearing on the punch using grease (to keep it from
falling).
-Insert the bearing in the crankcase; if needed, use
a mallet but do so with extreme care so as not to
damage the engine crankcase limit stop.
Specific tooling
020359Y 42x47-mm Adaptor
020364Y 25-mm guide
020376Y Adaptor handle
020360Y 52x55-mm Adaptor

Inspecting the crankshaft alignment

- Install the crankshaft on the support and measure
the displacement at the 4 points shown in the fig-
ure.
N.B.
IF VALUES OTHER THAN THOSE ALLOWED ARE DETEC-
TED, TRY STRAIGHTENING THE CRANKSHAFT BY IN-
SERTING A WOODEN WEDGE BETWEEN THE HALF
SHAFTS OR BY CLOSING THEM WITH A VICE AS NEE-
DED. IF EVEN AFTER THIS OPERATION THE VALUES ARE
NOT THOSE ADMITTED, REPLACE THE CRANKSHAFT.
Characteristic
Off-line maximum admitted - A
0.15 mm
Off-line maximum admitted - B
0.02 mm
Off-line maximum admitted - C
0.02 mm
Off-line maximum admitted - D
0.10 mm
- Check that the driving shaft cone, the tab seat, the oil seal capacity, the toothed gear and the threaded
tangs are in good working order.
- In case of failures, replace the crankshaft.
Specific tooling
ENG - 106
MSS Fly 50 4T