Motobecane 40 - Page 25

REASSEMBLING
THE ENGINE
CONT,D.
Fit
the
replacement
wrist
pin
using
piston pin
assembler
No. 100008.
Heat
(moderate'ly)
tne
pi
ston dome
(torch
)
unt
j
I smoke appears
.
(Thi
s
is
not
necessary for
a new
wrist
pin
that
is an easy sliding
fit.)
Insert the assembler
tip into
the
wrist
pin
(fig
. 7).
Push home while
pressing
against the opposite
sjde
of the
piston
to
prevent
unnecessary
pressure
on the
big-end bearing. The
assembler
stop
will comect'ly
position
the
pin
in
the
piston
(fig.
7)
Place
the cyljnder on the heated
piston
without
the rings or
piston
pin
clips
jnstalled.
The
cylinder wjll slide
down as the
temperature
evens
out.
This
operation
prevents piston
distortion
while
cooling
(fig.
B).
When the
piston/cylinder
assembly has
cooled
off,
check
con-rod align-
ment.
CHECKING ROD ALIGNMENT:
Secure the
cy'l
inder
with two washers
and
two opposite cylinder
head
nuts.
Bring
the
piston
to T.D.C.
Slide in
a tapered 0.07mm
feeler
gauge
between the
piston
(at
pin
holes)
and
cylinder.
If
the
gauge
slides freely
through one
side and
not through the other,
the rod
proves
to
be
out of
a'l
ignment. Remove the cy1
inder
and
pro-
ceed
with straightening.
Fig.
7
Fig. B
R0 2t
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