Sunbeam ALPINE I SERIES: APLINE II SERIES, Workshop Manual

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'W'S'M . 124
Section C
(Fuel System)
TO REMOVE FUEL PUMP FROM ENGINE
Disconnect the fuel pipes by undoing their unions
on the fuel pump body. Remove the two nuts
holding the pump to the engine crankcase and lift
away pump carefully noting the number of joints
used between the pump mounting face and the
crankcase face.
TO DISMANTLE FUEL PUMP (See Fig. 4)
Before commencing to dismantle the pump
thoroughly clean the exterior and make a mark
across the two flanges of the pump housing, as a
guide when reassembling.
Remove the six securing setscrews (11) and separate
the two halves of the main casting.
Turn the diaphragm and 'pull-rod assembly (13)
through an angle of 90 °
, when it may be disconnected
from its securing slot in the connecting link (20) and
withdrawn. Remove diaphragm spring (14).
Do not attempt to separate the four diaphragm layers.
Remove one circlip (24) from the rocker arm pin
and withdraw the pin (23).
The rocker arm (22) together with the connecting
link (20), spring (21) an washers (19) may now be
removed.
Withdraw the valve retainer screw (10) from in­
side the upper casting and remove the retainer
plate (9), valve assemblies (7) and valve retainer
gasket (8).
INSPECTION OF PARTS
Thoroughly clean all parts in paraffin. Those parts
that comprise the valve assemblies and retainers
should be washed separately from the other
dirtier components.
The diaphragm and pull rod assembly should be
renewed if there is any sign of hardening or
cracking.
Where any part of the hand priming mechanism
is broken the complete set of parts must be re­
newed, the outer ends of the spindle being riveted
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over by hand tools after correctly locating the
various components.
All badly worn parts must be renewed and very
little wear may be tolerated on the rocker arm pin,
holes and engagement slot in link, holes in rocker
arm, contact face of rocker arm or pull rod.
The valve assemblies cannot be dismantled but
should be tested for air-tight seatings by suction,
and renewed where necessary.
Check the valve retaining joint very carefully for
damage or distortion; it is advisable to renew this
gasket after dismantling as any fault preventing
correct seating of the valve assembly will greatly
decrease the efficiency of the pump.
Test the diaphragm spring, although this seldom
requires replacement. Where necessary ensure
that the replacement spring has the same
identification colour and consequently the same
strength as the original.
All gaskets and joints should be renewed as a matter
of routine, including the fabric oil seal washers
located round the diaphragm pull-rod.
TO REASSEMBLE FUEL PUMP
Refit valve retainer gasket, valves, valve retainer,
and secure in position with two retaining screws.
The valves must be assembled in the pump as
illustrated in Fig. 1. If fitted in any other way the
pump will not operate.
Assemble link, packing washers, rocker arm and
rocker arm spring in the body.
Insert rocker arm pin through the hole in the body,
at the same time engaging the packing washers,
link, and the rocker arm, then spring the retaining
clips into the grooves on each end of the pin. The
rocker arm pin should be a tap fit in the body.
The fitting of the rocker arm pin can be simplified
by first inserting a piece of 0·240" (6 mm.)
diameter rod through the pin hole in one side of
the body far enough to engage the rocker arm
washers and link, and then pushing the rocker arm