- - -
---------
Rolfs-Royce
&
Bentley-------
Air
Conditioning
System
Manual
SECTION
C.4
THE
COMPRESSOR,
CONTROL
VALVES
AND ANCILLARY UNITS
THE
COMPRESSOR
The compressor fitted to the Silver Cloud II and
Bentley S.2
is
the Tecumseh
HH
vertical twin
cylinder unit, with
an
Eaton
electromagnetic
clutch ( see Fig.
12).
Replacement
units
are
readily available
and
it
is
not
recommended
that
any
major
overhaul
work be
attempted,
except
by
the manufacturers.
The
valve plate, oil seal,
clutch
bearing,
and
the
brush
unit
may be renewed
as
necessary.
Fault
diagnosis
When
carrying
out
pressure tests, a low reading
on
the high pressure side indicates
an
inoperative
valve
or
defective gasket.
To
confirm
the
diagnosis,
reduce
the
engine
speed
to
'slow
idle'
and
turn the compressor low pressure service valve
clockwise
to
the forward-seated position. The
compound
gauge
should
register
12
in.
to
18
in.
Hg
almost
immediately
if
the
intake
valve
is
satisfactory.
Switch
off
and
observe
the
gauge
readings. A
leaking
shaft
seal will permit a rise to atmospheric
pressure. A rise
above
atmospheric
pressure
indicates a defective gasket,
or
that
the delivery
valve
is
not
seating correctly.
Before disturbing any compressor
joint,
close
the service valves
to
seal
off
the
system
and
release the pressure from the head
as
described
for the oil level check.
When the cylinder head
is
removed, examine
the valves
and
cylinder bores. A
damaged
valve
will necessitate changing the valve plate assembly;
where a
cylinder
bore
is badly
scored,
a replace-
ment
compressor
must be fitted.
When
re-assembling, clean all
joint
faces care-
fully
and
immerse
the
new
gaskets
in clean
refrigerant oil before
fl tting.
The
compressor
-
To
remove
and
fit
Remove the magnetic
clutch
(see Page
16).
Forward-seat
both
compressor service valves
and release the
compressor
pressure, as described
for
the
oil level check. Release the Allen screws
securing the service valves
to
the
compressor.
Remol/e the gauze filter from the compressor inlet
port, together with the fibre washer.
Unscrew the four compressor securing setscrews
situated
beneath
the
compressor
mounting
bracket
and
remove
the
compressor
unit, leaving
the service valves
connected
to
the pipes.
When fitting the compressor, secure all
connections, then purge the
air
(see Page
18),
and
turn
both
service valves anti-clockwise until fully
back-seated.
Test
for leaks
under
operating
conditions
and
static conditions. Install the gauge set, check the
pressures,
and
ensure
that
the
complete
system
is
functioning correctly.
The
magnetic
clutch
-
compressor
The
clutch consists
of
an
electromagnetic
fly-
wheel driven
by
twin 'Vee' belts from the engine,
and
a drive
plate
attached
hy a flexible coupling
plate
to
the
forward
end
of
the
compressor
crankshaft (see Fig.
3}.
Page
15
To Next Page
Loading...
