Repair Manual

1.14 Every 2 years - regardless of mileage
surfaces of the vehicle. Rinse off spills
immediately with plenty of water. Never
leave antifreeze lying around in an open
container, or in a puddle in the driveway or
on the garage floor. Children and pets are
attracted by its sweet smell, but antifreeze
can be fatal if ingested.
1 With the engine completely cold, cover the
expansion tank cap with a wad of rag, and
slowly turn the cap anti-clockwise to relieve
any pressure in the cooling system (a hissing
sound will normally be heard). Wait until any
pressure remaining in the system is released,
then continue to turn the cap until it can be
removed.
2 Move the heater control to the ‘HOT’
position. This is necessary in order to help
drain the heater circuit, as a mechanical
temperature valve is used in the system.
3 Position a suitable container beneath the
left-hand side of the radiator, then release the
retaining clip and ease the bottom hose from
the radiator stub. If the hose joint has not
been disturbed for some time, it will be
necessary to gently twist the hose to break
the joint. Do not use excessive force, or the
radiator stub could be damaged. Allow the
coolant to drain into the container.
4 If the coolant has been drained for a reason
other than renewal, then provided it is clean
and less than two years old, it can be re-used,
though this is not recommended.
5 Once all the coolant has drained, reconnect
the hose to the radiator and secure it in
position with the retaining clip.
Cooling system flushing
6 If coolant renewal has been neglected, or if
the antifreeze mixture has become diluted,
then in time, the cooling system may gradually
lose efficiency, as the coolant passages
become restricted due to rust, scale deposits,
and other sediment. The cooling system
efficiency can be restored by flushing the
system clean.
7 The
radiator
should be flushed
independently of the engine, to avoid
unnecessary contamination.
Radiator flushing
6 To flush the radiator disconnect the top and
bottom hoses from the radiator, with
reference to Chapter 3.
9 Insert a garden hose into the radiator top
inlet. Direct a flow of clean water through the
radiator, and continue flushing until clean
water emerges from the radiator bottom
outlet.
10 If after a reasonable period, the water still
does not run clear, the radiator can be flushed
with a good proprietary cooling system
cleaning agent. It is important that the
manufacturer’s instructions are followed
carefully. If the contamination is particularly
bad, remove the radiator and invert it then
insert the hose in the radiator bottom outlet
and reverse-flush the radiator.
Engine flushing
11 To flush the engine, remove the
thermostat as described in Chapter 3 and
leave the cover disconnected.
12 With the top hose disconnected from the
radiator, insert a garden hose into the radiator
top hose. Direct a clean flow of water through
the engine, and continue flushing until clean
water emerges from the thermostat housing in
the cylinder head outlet.
13 On completion of flushing, refit the
thermostat and reconnect the hoses with
reference to Chapter 3.
Cooling system filling
14 Before attempting to fill the cooling
system, make sure that all hoses and clips are
in good condition, and that the clips are tight.
Note that an antifreeze mixture must be used
all year round, to prevent corrosion of the
engine components (see following sub-
Section).
15 Check that the heater controls are set to
“HOT”, then remove the rubber strip and
plastic cover from the plenum chamber
behind the engine compartment, and loosen
the bleeder screw on the heater temperature
control valve.
16 Slowly pour the coolant into the
expansion tank. While doing this watch the
heater bleeder, and tighten the screw when
bubble-free water comes out. If the coolant is
being renewed, begin by pouring in a couple
of litres of water, followed by the correct
quantity of antifreeze, then top-up with more
water.
17 Once the level in the expansion tank starts
to rise, squeeze the radiator top and bottom
hoses to help expel any trapped air in the
system. Once all the air is expelled, top-up the
coolant level to the “MAX” mark and refit the
expansion tank cap.
16 Start the engine and run it until it reaches
normal operating temperature and the electric
cooling fan switches on, then stop the engine
and allow it to cool.
19 Check for leaks, particularly around
disturbed components. Check the coolant
level in the expansion tank, and top-up if
necessary. Note that the system must be cold
before an accurate level is indicated in the
expansion tank. If the expansion tank cap is
removed while the engine is still warm, cover
the cap with a thick cloth, and unscrew the
cap slowly to gradually relieve the system
pressure (a hissing sound will normally be
heard). Wait until any pressure remaining in
the system is released, then continue to turn
the cap until it can be removed.
26 Finally refit the plastic cover and rubber
strip to the plenum chamber, and reset the
heater controls as necessary.
Antifreeze mixture
21 The antifreeze should always be renewed
at the specified intervals. This is necessary
not only to maintain the antifreeze properties,
but also to prevent corrosion which would
otherwise occur as the corrosion inhibitors
become progressively less effective.
22 Always use an ethylene-glycol based
antifreeze which is suitable for use in mixed-
metal cooling systems. The quantity of
antifreeze and levels of protection are
indicated in the Specifications.
23 Before adding antifreeze, the cooling
system should be completely drained,
preferably flushed, and all hoses checked for
condition and security.
24 After filling with antifreeze, a label should
be attached to the expansion tank, stating the
type and concentration of antifreeze used,
and the date installed. Any subsequent
topping-up should be made with the same
type and concentration of antifreeze (see
illustration).
25 Do not use engine antifreeze in the
windscreen/tailgate washer system, as it will
cause damage to the vehicle paintwork. A
screenwash additive should be added to the
washer system in the quantities stated on the
bottle.
23.24 Topping up the cooling system
with antifreeze