PIAGGIO Vespa 125 1955 Manual Para Estaciones De Servicio página 150

Fig. 38
Reaming small end bush.
• Interpose spacer washer between tool and clamp,
Escariado casquillo pie de biela.
• Arandela de separaci6n entre soporte y util.
120
381500/7
381505/7
38151 1 0/7
3
ef
•j)
1
Ei" ""
m) Run the reamer 381500 /7 through again
( for the first oversiz. operation, run through
the reamer 381505 /7 and for the second
oversizi ng operation the reamer 3815 l 0 /7).
To facilitate the flow of lubrication when the engine
is functioning, on fitting the wrist pin and small end
bush execute four lead chamfers
«
fig. 39.
If available it is preferable t�at this operation be
carried out on a machine using the milling cutter as
indicated: however a rat tail file of dia. 2.5 to 3
mm can be used to obtain the required results.
Having completed the operation carefully clean the
machined area as so as to remove all the residual
swarf. Control the con rod small end bore using the
plug T.16160/C (for normal bore); T.16161/C (for
1st o/s); T. 16763/C (for 2nd o/s): the plug gauge
when introduced should slide in gently under hand
pressure.
OversiEed wrist pin: For assembling the l st o/s
wrist pin, rough and finish ream the wrist pin hou­
sing on the piston, respectively with the reamer
3815 0 4 and 381505 ; during this operation it is
advisable to use the work holder ( with centres for
the piston which maintains the latter components
bore axis in a fixed position) T. 0020897.
For the 2nd o/s wrist pin the reamers to use cor­
r e s po n d respectively to the drg. Nos. 381509 -
3815 l 0.
as indicated in
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0