Ford Fiesta (1989-1995). Manual - part 27

body, then measure the distance between the
gasket and the step on the float.
17 If the measurement is not as specified,
adjust by bending the tag on the float, then re-
check.
18 Refitting should be carried out in
accordance with paragraphs 11 to 14
inclusive.

15 Carburettor (Weber TLM) -

removal and refitting

Note: Refer to the warning note in Section 1
before proceeding. New gaskets will be
required when reassembling. A tachometer
and an exhaust gas analyser (CO meter) will
also be required to check the idle speed and
mixture settings on completion.

Removal

1 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
2 Remove the air cleaner as described in
Section 2.
3 Disconnect the accelerator inner and outer
cable from the carburettor (Section 3).
4 Disconnect the choke inner and outer cable
from the carburettor (Section 6).
5 Disconnect the fuel feed hose from the
carburettor, and plug its end to avoid spillage
and prevent dirt ingress. If a crimped type
hose clip is fitted, cut this free taking care to
avoid damage to the hose.
6 Where applicable, disconnect the electrical
lead from the anti-dieseling (fuel cut-off)
solenoid, and all relevant carburettor vacuum
pipes (having labelled them for correct
subsequent refitting).
7 Remove the two Torx head screws securing
the carburettor to the inlet manifold, then
withdraw it from the vehicle (see illustration).

Refitting

8 Clean the inlet manifold and carburettor
gasket mating faces.
9 Refit in the reverse order of removal. Fit a
new gasket, and tighten the retaining screws
securely. Ensure that the fuel supply hose
connection to the carburettor is securely

fitted, using a new screw type retaining clip.
10 Reconnect the accelerator cable, and
adjust it as described in Section 3.
11 Reconnect the choke cable, and adjust it
as described in Section 6.
12 Refer to Section 2 and refit the air cleaner.
13 When the battery is reconnected, start
and warm up the engine then check the idle
speed and mixture settings as described in
Chapter 1.

16 Accelerator pump diaphragm

(Weber TLM carburettor) -
removal and refitting

Note: Refer to the warning note in Section 1
before proceeding.

Removal

1 Remove the carburettor as described in
Section 15 and place it on a clean flat work
surface.
2 Remove the accelerator pump cover
retaining screws and detach the cover.
3 Withdraw the diaphragm and spring. Check
the diaphragm for damage, and renew if
evident.

Refitting

4 Clean the carburettor and cover mating
faces.

5 Refit the spring and diaphragm to the
carburettor, aligning the diaphragm with its
cover retaining screw holes. Position the
actuating lever on its cam, then carefully
press the cover against the diaphragm and
secure with its retaining screws.
6 Refit the carburettor as described in
Section 15.

17 Carburettor (Weber TLM) -

dismantling, cleaning,
inspection and reassembly

Note: Refer to the warning note in Section 1
before proceeding. Check parts avail-
ability before dismantling. If possible, obtain
an overhaul kit containing all the relevant
gaskets, seals, etc, required for reassembly
prior to dismantling the carburettor.

Dismantling

1 Remove the carburettor as described in
Section 15 and place it on a clean flat work
surface.
2 Clean the exterior of the carburettor, then
undo the two retaining screws and lift off the
upper carburettor body (see illustration).
3 Remove the float and needle valve from the
carburettor upper body, as described in
Section 14.
4 Remove the accelerator pump components

4A•8 Fuel system – carburettor engines

17.2 Exploded view of the carburettor (Weber TLM)

15.7 Removing one of the two Torx head

screws (arrowed) securing the carburettor

to the inlet manifold (Weber TLM

carburettor)

1595Ford Fiesta Remake

A Upper body
B Choke mechanism
C Accelerator pump

assembly

D Accelerator pump

discharge tube

E Fast-idle speed

adjusting screw

F Throttle housing
G Idle speed adjusting

screw

H Anti-dieseling (fuel

cut-off) solenoid

J Power valve assembly
K Float
L Idle mixture adjusting

screw

as described in Section 16. The power valve
assembly can also be removed in a similar
fashion.
5 Prise free the accelerator pump discharge
tube, but take care not to damage it or the
carburettor body.
6 Remove the jets and emulsion tubes as
required, making careful notes of their
respective locations for reassembly.

Cleaning and inspection

7 Soak out the fuel in the float chamber using
a clean rag; this must be safely disposed of.
Clean the float chamber, jets, drillings and
passages with clean petrol. The careful use of
an air line (or footpump) is ideal to blow out
the upper and lower bodies. Never use a
piece of wire for cleaning purposes.
8 Examine all of the carburettor components
for signs of damage or wear, paying particular
attention to the diaphragms, throttle spindle
and plates, and needle valve. Renew all
diaphragms, sealing washers and gaskets as
a matter of course.

Reassembly

9 Refit the emulsion tubes and jets to their
locations as noted during dismantling.
10 Refit the accelerator pump discharge
tube.
11 Refit the accelerator pump and power
valve assemblies as described in Section 16.
12 Refit the needle valve and the float, and
adjust the float setting as described in Sec-
tion 14.
13 Locate a new gasket onto the mating
face, then refit the carburettor upper body to
the main body. As they are reassembled, take
care not to snag the float on the carburettor
main body. Fit and tighten the retaining
screws to secure.
14 On completion, refit the carburettor as
described in Section 15.

18 Carburettor (Weber TLDM) -

description

The carburettor is of twin venturi,

downdraught type, featuring a fixed size main
jet system, adjustable idle system, a
mechanically-operated accelerator pump, and
a vacuum-operated power valve. A manually-
operated cold start choke is fitted, and a
throttle kicker is used on certain models.

In order to comply with emission control

regulations and maintain good fuel
consumption, the main jets are calibrated to
suit the 1/4 to 3/4 throttle range. The power
valve is therefore only used to supply
additional fuel during full-throttle conditions.

The accelerator pump is fitted to ensure a

smooth transmission from the idle circuit to
the main jet system. As the accelerator pedal
is depressed, a linkage moves the diaphragm
within the accelerator pump, and a small

quantity of fuel is injected into the venturi, to
prevent a momentary weak mixture and
resultant engine hesitation.

The manually-operated choke features a

vacuum-operated pull-down mechanism
which controls the single choke plate under
certain vacuum conditions.

On CTX automatic transmission models,

the throttle kicker acts as an idle speed
compensator for when the transmission shift
lever positions R, D or L are selected. The
throttle kicker is operated by vacuum supplied
from the inlet manifold. When the appropriate
transmission shift lever position is selected,
the throttle kicker control solenoid allows the
vacuum to pass to the throttle kicker which
maintains the idle speed by means of a
diaphragm and mechanical linkage.

On manual transmission models, the

throttle kicker (when fitted) acts as a damper
by slowing down the closing action of the
throttle plate. Under deceleration, this
maintains the combustion of the air/fuel
mixture entering the cylinders, thus improving
the exhaust emission levels. A vacuum
sustain valve controls the carburettor-sourced
vacuum applied to the throttle kicker unit; this
allows the vacuum slowly to decay, allowing
normal engine idling speed to be achieved.

An anti-dieseling (fuel cut-off) solenoid is

fitted to prevent the possibility of the engine
running on after the ignition is switched off.

Idle speed and mixture adjustment

procedures are described in Chapter 1, but it
is important to note that accurate adjustments
can only be made using the necessary
equipment.

19 Carburettor (Weber TLDM) -

fast-idle speed adjustment

Note: Before carrying out any carburettor
adjustments, ensure that the spark plug gaps
are set as specified, and that all electrical and
vacuum connections are secure. To carry out
checks and adjustments, an accurate
tachometer and an exhaust gas analyser (CO
meter) will be required.
1 Check the idle speed and mixture settings

are as specified (as described in Chapter 1).
These must be correct before
checking/adjusting the fast-idle speed.
2 With the engine at its normal operating
temperature, and a tachometer connected in
accordance with the manufacturer’s
instructions, switch the engine off, then
remove the air cleaner (if not already done) as
described in Section 2.
3 Actuate the choke by pulling the control
knob fully out, then start the engine and note
the engine fast-idle speed. Compare it with
the specified speed.
4 If adjustment is required, turn the fast-idle
adjusting screw clockwise to decrease, or
anti-clockwise to increase, the fast-idle speed
(see illustration).
5 Recheck the fast-idle and basic idle
speeds.
6 On completion of the adjustment, stop the
engine, detach the tachometer and CO meter,
reconnect the radiator cooling fan lead, and
refit the air cleaner.

20 Needle valve and float (Weber

TLDM carburettor) - removal,
refitting and adjustment

Note: Refer to the warning note in Section 1
before proceeding. New gaskets and a washer
(seal) will be required when reassembling. A
tachometer and an exhaust gas analyser (CO
meter) will also be required to check the
idle speed and mixture settings on
completion.

Removal and refitting

1 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
2 Remove the air cleaner as described in
Section 2.
3 Clean the exterior of the carburettor, then
disconnect the fuel supply hose and the anti-
dieseling solenoid wiring.
4 Disconnect the choke control cable.
5 Undo and remove the six retaining screws
(four of which are Torx type) and carefully lift
the carburettor upper body clear (see
illustrations).
6 Invert and support the upper body of the
carburettor for access to the float and pivot.

Fuel system – carburettor engines 4A•9

19.4 Fast-idle speed adjusting screw

(arrowed) (Weber TLDM carburettor)

1595Ford Fiesta Remake

20.5a Remove the carburettor upper body

securing screws . . .

Lightly tap out the float pivot pin, then
withdraw the float, taking care not to distort
the arms of the float (see illustrations).
7 Unscrew the needle valve housing, and
extract it from the carburettor upper body.
Collect the washer from the threads of the
needle valve housing.
8 Clean and inspect the components for
signs of damage or wear, particularly the pivot
holes in the float arm. Check the float for signs
of leakage, by shaking it to see if it contains
fuel. Clean the float chamber and jets (refer to
Section 24 for details). Renew any
components as necessary.
9 Fit a new washer over the needle valve
housing threads, and then carefully screw the
valve unit into position in the upper body.
10 Refit the needle valve, float and retaining
pin, ensuring that the tag on the float engages
with the ball and clip of the needle valve.
11 Before refitting the upper body to the
carburettor, check and if necessary adjust the
float level as described in paragraphs 16
to 18. Also check the float and needle valve
for free movement.
12 Clean the gasket contact faces, then
locate a new gasket and refit the upper body
to the carburettor.
13 Reconnect the fuel supply hose, anti-
dieseling solenoid wiring and the choke cable.
Adjust the choke cable as described in
Section 6. If the fuel hose was originally
secured with a crimped type clip, discard it
and fit a screw type clip.

14 Refit the air cleaner as described in
Section 2.
15 Reconnect the battery earth lead, then
restart the engine and check the idle speed
and mixture settings. Adjust if necessary as
described in Chapter 1.

Float level adjustment

16 With the carburettor upper body removed
as described in paragraphs 1 to 5 inclusive,
proceed as follows.
17 Support the carburettor upper body
vertically, ensuring that the needle valve is
shut off. Locate the new upper body gasket
onto the carburettor upper body, then
measure the distance between the gasket and
the bottom of the float (see illustration).
18 If the measurement is not as specified,
adjust the setting by carefully bending the tag
on the float as required, then recheck.
19 Refit with reference to paragraphs 12
to 15 inclusive.

21 Throttle kicker unit (Weber

TLDM carburettor) - removal,
refitting and adjustment

Note: A tachometer and exhaust gas analyser
(CO meter) will be required to check and make
any adjustment necessary.

Removal and refitting

1 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
2 Refer to Section 2 and remove the air
cleaner.
3 Detach the vacuum hose from the kicker
unit. Undo the two retaining screws, detach
the linkage and remove the kicker unit (see
illustration).
4 Refitting the kicker unit is a reversal of the
removal procedure. If the unit is to be
checked for adjustment, loosely locate the air
cleaner, reconnect the inlet air temperature
sensor multi-plug and the battery earth lead,
then proceed as follows.

Adjustment

5 Start and run the engine up to its normal
operating temperature (at which point the
cooling fan will start to operate) then switch
the engine off.
6 Remove the air cleaner again, then detach
the wiring connector of the cooling fan
thermostatic switch. Bridge the terminals in
the connector with a suitable piece of wire to
actuate the cooling fan and keep it running.
Start the engine and run it at 3000 rpm for
30 seconds to stabilise it, then release the
throttle and check (and if necessary adjust)
the idle speed and mixture settings as
described in Chapter 1. Stop the engine.

4A•10 Fuel system – carburettor engines

21.3 General view of throttle kicker

arrangement (Weber TLDM carburettor)

A Tamperproof plug covering adjusting point
B Throttle kicker securing screws
C Vacuum supply pipe

20.17 Float level adjustment (Weber TLDM

carburettor)

A Float level setting dimension
B Adjusting tag

20.6c Remove the needle valve housing

and its washer

20.6b . . . then detach the float and needle

valve

20.6a Slide out the float retaining pin . . .

20.5b . . . then detach the carburettor

upper body

1595Ford Fiesta Remake

7 Detach the vacuum hose between the
throttle kicker and the inlet manifold at source
(but not the vacuum supply to the ignition
module). Connect a new length of vacuum
hose directly between the manifold and the
kicker unit.
8 Restart the engine and check the engine
speed. The throttle kicker should increase the
engine speed above its normal idle. Check the
speed registered against the specified throttle
kicker operating speed.
9 If required, the throttle kicker speed can be
adjusted by prising free the tamperproof plug
and the adjustment screw turned as
necessary

(see illustration 21.3).

10 When the adjustment is complete, stop
the engine, fit a new tamperproof plug,
disconnect the temporary vacuum hose
(between the manifold and the kicker unit) and
reconnect the original hose (between the
carburettor and the kicker unit).
11 Remove the bridging wire, and reconnect
the cooling fan thermostatic switch multi-
plug. Refit and secure the air cleaner, and
disconnect the tachometer and CO meter to
complete.

22 Throttle kicker control solenoid

(Weber TLDM carburettor) -
removal and refitting

Removal

1 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
2 Disconnect the multi-plug from the solenoid
(see illustration).
3 Remove both vacuum pipes, having
labelled them for correct subsequent refitting.
4 Remove the screw securing the solenoid
and mounting bracket assembly to the
bulkhead panel, then withdraw the assembly
from the vehicle.

Refitting

5 Refitting is a reversal of the removal
procedure, ensuring that the locating lug
snaps into position and that the vacuum pipes
are connected to their correct terminals.

23 Carburettor (Weber TLDM) -

removal and refitting

Note: Refer to the warning note in Section 1
before proceeding. New gaskets will be
required on refitting, and a tachometer and an
exhaust gas analyser will be required on
completion.

Removal

1 Disconnect the battery negative (earth) lead
(refer to Chapter 5A, Section 1).
2 Remove the air cleaner as described in
Section 2.
3 Disconnect the accelerator cable from the
carburettor (Section 3).
4 Disconnect the choke cable from the
carburettor (Section 6).
5 Disconnect the fuel hose from the
carburettor, and plug its end to prevent fuel
spillage and the ingress of dirt. If a crimped
type hose clip is fitted, cut it free, but take
care not to damage the hose. Crimped clips
must be discarded and replaced with screw
type clips during refitting.
6 Disconnect the wiring from the anti-
dieseling solenoid.
7 Unscrew and remove the four carburettor-
to-manifold retaining Torx head screws, then
carefully lift the carburettor from the manifold
(see illustration).

Refitting

8 Clean the carburettor and manifold gasket
mating faces.

9 Refit in the reverse order of removal. Fit a
new gasket, and tighten the retaining screws
securely. Ensure that the fuel supply hose
connection to the carburettor is
securely fitted, using a new screw type
retaining clip.
10 Reconnect the accelerator cable, and
adjust it as described in Section 3.
11 Reconnect the choke cable, and adjust it
as described in Section 6.
12 Refer to Section 2 and refit the air cleaner.
13 When the battery is reconnected, start
and warm up the engine then check the idle
speed and mixture settings as described in
Chapter 1.

24 Carburettor (Weber TLDM) -

dismantling, cleaning,
inspection and reassembly

Dismantling

1 With the carburettor removed from the
vehicle, prepare a clean, flat work surface
prior to commencing dismantling. The
following procedures may be used for partial
or complete dismantling, as required.
2 Clean the exterior of the carburettor, then
undo the two retaining screws and lift the
upper carburettor body from the lower section
(see illustration overleaf).
3 Remove the float and needle valve from the
carburettor upper body, as described in
Section 20.
4 Unscrew and remove the anti-dieseling
solenoid from the upper body, but ensure that

Fuel system – carburettor engines 4A•11

23.7 Four Torx head screws (arrowed) secure the carburettor to

the inlet manifold (Weber TLDM carburettor)

22.2 Throttle kicker control solenoid

A Multi-plug B Vacuum pipes C Securing screw

1595Ford Fiesta Remake

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