Sunbeam ALPINE I SERIES: APLINE II SERIES, Workshop Manual

Page: 240 / 413

WSM. 124
Section H (Rear Suspension)
the piston is moving relatively towards the foot
valve (13) fluid pressure opens the piston valve
(21) against the coil spring load and fluid passes
through the ports (7) in the piston valve from
the lower half of the cylinder (A) to the upper
part of the cylinder (B). The excess fluid dis­
placed from the cylinder by the piston passes via
the ports (5) in the piston rod guide (17) through
the filter (6) and down the rebound valve tube
(9) opening the rebound valve (10) against the
coil spring load into the reservoir (C).
On the slow bump strokes, damping is controlled
by calibrated bleed grooves on the face of the
foot valve (13).
On the fast rebound strokes when the piston is
moving relatively towards the piston rod guide
(17) the piston valve (21) closes and again fluid
passes through the ports (5) in the piston rod
guide (17) through the filter (6) down the re­
bound valve tube (9) opening the rebound valve
(10) against the coil spring load and into the reser­
voir (C). At the same time the lower part of
the cylinder (A) is replenished with fluid as the
foot valve plate (12) opens to allow recuperation
from the reservoir (C).
On slow rebound strokes, fluid passes through a
calibrated bleed groove in the face of the piston
valve seat.
Any fluid which passes between the piston rod
(2) and the piston rod guide bearing Is prevented
from escaping by the multi-lip piston rod seal (3).
Undue Internal fluid pressure on this seal is re­
lieved as the fluid passes through a port to the
drain tube (18), the lower end of which Is im­
mersed in the reservoir fluid to prevent aeration.
Testing
When there is any question of suspension not
being adequately damped, the condition of the
following should be considered: road springs, tyre
pressures, bump rubbers, and bump rubber seats,
as these carry the full bump load of the suspension.
Pa1e13
Fla. 7. Details of shock absorber Alpine Ill
If a shock absorber does not appear to function
satisfactorily an Indication of Its resistance can be
obtained by carrying out the following check:-
Remove the shock absorber from its mounting.
Place the shock absorber vertically in a vice.
holding by the lower
eye
between two,
pieces of wood.