Hold connecting rod with both hands, pull
and push, and
any
up and
down
play
can
be
felt.
DO NOT USE SIDE PRESSURE.
Do
not
mistake
side float for end play.
A
small
amount
of
rock
is
of
no
impor-
tance.
If
any appreciable
up
and
down
movement
is
present a
new
crankpin bearing
is
neces-
sary.
The dismantling
of
the
flywheels
and
fitting of crankpin
is
a
skilled
job
requiring
equipment not normally
available
to
the
average
rider. The
flywheel
assembly
should
be returned to the
works
for
this
replace-
ment.
29.
REMOVING
ENGINE
FROM
FRAME.
Remove
t:4e
tank (para. 6),
magdyno
(para.
27) and exhaust valve lifter cable.
Remove
carburetter,
which
may
be
left
suspended
from cables,
remove
exhaust pipe
and silencer, a " C
''
spanner
is
supplied in
tool kit to fit exhaust pipe
locking
ring on
O.H.V.
model.
Remove
clip bolts and nuts,
and
silencer
bolt, and the pipe and silencer
can
be
removed
as
one
unit.
Remove
·
oil
pipes from the
crankcase.
If
the
oil
has
not been drained from the oil tank,
plug the end of the
feed
pipe.
Remove
oil
bath, engine sprocket, and
clutch. (Para. 36.)
Remove
front and rear engine plates
com-
pletely.
Remove
engine
cradle bolts and lift
engine
clear
of
frame.
30.
PARTING
OF
THE
CRANKCASE
HALVES.
Remove
crankcase
drain plug and drain
any
oil
that
may
be
in
the
sump.
Remove cylinder barrel (Para. 9), piston
(Para. 17), timing gear and oil pump (Para. 25).
Remove
key
from
driving shaft.
Remove
all the
crankcase
bolts and stud
nuts,
also
the
cheese
headed
screws
from
sump.
Crankcase
halves
can
now
be parted.
Remove
timing side
first.
If
leverage
is
necessary,
revolve
flywheels
until the crankpin
is
at the mouth
of
the
case,
place
a lever against the crankpin nut and
lever
outwards.
To
remove
the driving
side
of the
case,
lift
the half
of
the
case
with the
flywheels
and
lightly drop the end of the driving shaft on
15
to a
block
of hard
wood,
when the case should
leave
the shaft.
31.
REMOVAL
OF
BEARINGS
FROM
CRANKCASE.
It should be
possible
to
remove
the bearings
from
the
case
by
tapping a shaft through the
bearings, the shaft
having
a diameter slightly
larger than the engine shaft, but
small
enough
to
pass
through the bearing, should be bearing
be
tight in the
case,
without
damage.
If
the bearings are
too
tight
in
the housing
to
be
removed
by this method, the
case
should
be
heated round the bearing housings,
when
they
should
drop out.
Do not heat
case
sufficiently
to
destroy the
temper
of
the bearings and do not
use
a con-
centrated
flame.
32.
FITl'INGS
OF
BEARINGS
TO
CRANKCASE.
Test bearings, to
be
a sliding fit
on
shafts.
Press the ball bearing lightly in to the
driving side of the
case.
Fit the spacing washer
next
to the ball
bearing.
Press the roller bearing lightly in
to
driving
side of the
case.
33.
ASSEMBLY
OF
CRANKCASE.
Fit
flywheels
into case, and
fit
and tighten
all
bolts.
Test
for
side
float
in
the
flywheels,
there
should
be
.005".
If the
float
is
excessive,
remove
wheels
from
case.
Fit pen steel
washers
to the engine and
timing
shafts
to
take
up
the
excess
of
float.
Fit the
same
thickness
of
washers
on
each
shaft,
keeping
the
wheels
central
in
the
case.
Check
side
float.
If
the side
float
is correct,
check
connecting
rod for being central in
case.
There
is
side
float
in the big-end.
Place
fingers
on the bottom of the connect-
ing rod and push rod
towards
the timing
side
of
the
case.
Measure the distance from the end of the
small-end
bush to the side of the
crankcase
mouth
on
the timing
side.
Push rod to driving side of
case
and take
the
same
measurement, from the driving side.
The
two
measurements should be within
1 /64"
of
each
other.
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