engine FORD SIERRA 1985 1.G Routine Manintenance And Servicing Owner's Manual

4Certain SOHC models have a bleed spigot
on the thermostat housing, which is covered
by a rubber cap. The cap should be removed
from the spigot before commencing draining
(see illustration).
5With the expansion tank cap removed,
place a suitable container beneath the
radiator bottom hose or drain plug as
applicable.
6On early models, loosen the clip and ease
the bottom hose away from the radiator
outlet. On later models, unscrew the drain
plug (see illustrations).Allow the coolant to
drain into the container.
7On SOHC models, place a second
container beneath the drain plug on the
right-hand side of the cylinder block (see
illustration).Unscrew the drain plug and
allow the coolant to drain into the container.
No cylinder block drain plug is fitted on CVH
and DOHC models.8Dispose of the drained coolant safely.
9After some time the radiator and engine
waterways may become restricted or even
blocked with scale or sediment, which
reduces the efficiency of the cooling system.
When this occurs, the coolant will appear
rusty and dark in colour and the system
should then be flushed.
10Disconnect the top hose from the radiator,
then insert a garden hose and allow water to
circulate through the radiator until it runs clear
from the outlet.
11Insert the hose in the expansion tank filler
neck and allow water to run out of the bottom
hose (and cylinder block on SOHC models)
until clear. If, after a reasonable period the
water still does not run clear, the radiator can
be flushed with a good proprietary cleaning
agent.
12Disconnect the inlet hose from the inlet
manifold, connect the garden hose and allow
water to circulate through the manifold,
automatic choke (where applicable), heater
and out through the bottom hose until clear.
13In severe cases of contamination the
system should be reverse flushed. To do this,
remove the radiator, invert it and insert a hose
in the outlet. Continue flushing until clear
water runs from the inlet.
14The engine should also be reverse
flushed. To do this, remove the thermostatand insert the hose into the cylinder head on
SOHC models, or into the inlet manifold on
CVH and DOHC models. Continue flushing
until clear water runs from the bottom hose
(and cylinder block on SOHC models).
15Where applicable, refit the radiator and
the thermostat.
16Reconnect any disturbed hoses and refit
and tighten the cylinder block drain plug
and/or radiator drain plug, as applicable.
17On SOHC models fitted with a bleed
spigot on the thermostat housing, ensure that
the rubber cap is removed before refilling the
system.
18Pour coolant in through the expansion
tank filler hole until the level is up to the
“MAX” mark.
19Where applicable, refit the rubber cap to
the bleed spigot when coolant starts to
emerge from the spigot. Tighten the clip.
20Squeeze the coolant hoses to help
disperse air locks. Top-up the coolant further
if necessary, then refit and tighten the
expansion tank cap.
21Run the engine up to operating
temperature, checking for coolant leaks. Stop
the engine and allow it to cool, then re-check
the coolant level. Top-up the level as
necessary, taking care to avoid scalding as
the expansion tank cap is removed.
1•22Every 36 000 miles or 3 years
46.4 Unscrew the clip and remove the
rubber cap from the bleed spigot -
SOHC models46.6b Radiator drain plug (arrowed) - later
CVH models
46.7 Cylinder block drain plug (arrowed) -
SOHC models (engine removed)
46.6a Disconnect the bottom hose from
the radiator - early OHC models