Pressure FIAT PUNTO 1995 176 / 1.G Repair Manual

6*2 Clutch
3 Clutch cable -removal and refitting
Note: This procedure applies to models fitted with a cabfe-opemted dutch
release mechanism.
Removal 1 Remove the battery and tray as described In Chapter SA. If necessary, also remove the Inlet air ducting for Improved access as described In the relevant part of Chapter 4. 2 Unscrew the adjustment locknut and adjuster nut from the end of the cable fitting, (hen release the inner and outer cables from the transmission housing. Note the position of the damper biock. 3 Working Inside the vehicle, unhook the inner cable from the top of the clutch pedaL 4 Returning to the engine compartment, unscrew the nuts securing the outer cable to the bulkhead, then withdraw the cable assembly from the engine compartment. Refitting 5 Apply a smear of multi-purpose grease to the cable end fittings, then pass the cable through the bulkhead. Refit and tighten the nuts. 6 Inside the vehicle hook the inner cable onto the top of the clutch pedal. 7 in the engine compartment, attach the outer cable to the transmission housing and refit the damper block and nuts lo Ihe inner cable end. fi Adjust the cable as described in Section 2. 9 Refit the air ducting and battery with reference to Chapters 4 and 5A
4 Clutch hydraulic system -
i
Note: This procedure applies to models fitted with the hydraulicalty-operated clutch release mechanism.

A


Warning: Hydraulic fluid Is poisonous; thoroughly wash off spllfs from bare skin without delay. Seek Immediate medical advice If any fluid is swallowed or gets into the eyes. Certain types of hydraulic fluid are Inflammable and may ignite when brought into contact with hot components; when servicing any hydraulic system, It is safest to assume that the fluid IS Inflammable, and to take precautions against the risk of fire as though ft were petrof that was being handled. Hydraulic fluid Is an effective paint stripper and will also attack many plastics. If spillage occurs onto painted bodywork or fittings, ft should be washed off Immediately, using copious quantities of fresh water. It Is also hygroscopic - It can absorb moisture from the air, which then renders it useless. Old fluid may have
suffered contamination, and should never be re-used. When topping-up or renewing tho fluid, always use tha recommended grade, and ensure that It comes from a new seated container. General information 1 Whenever the clutch hydraulic lines are disconnected for service or repair, a certain amount of air will enter the system. The presence of air In any hydraulic system will Introduce a degree of elasticity, and in the clutch system this will translate into poor pedal feel and reduced travel, leading to inefficient gear changes and even clutch system failure. For this reason, the hydraulic lines must be sealed using hose clamps before any work la carried out and then on completion, topped up and bled to remove any air bubbles. 2 To seal off Ihe hydraulic supply to tha clutch slave cylinder, fit a proprietary brake hose clamp to the flexible section of the hose located over the transmission and tighten it securely. It will be necessary to remove the battery and battery tray to access the hose. 3 The most effective way of bleeding the clutch hydraulic system is to use a pressure brake bleeding kit. These are readily available in motor accessories shops and are extremely effective: the following sub-section describes bleeding the clutch system using such a kit. The alternative method is to bleed the system by depressing tho clutch pedal • refer to Chapter 9. Section 11, for details of this method.
Bleeding 4 Remove the protective cap from Ihe bleed nipple on the slave cylinder. Access can be improved by removing the battery and tray with reference to Chapter 5A. 5 Fit a ring spanner over the bleed nipple head, but do not slacken it at this point. Connect a length of dear plastic hose over the nipple and insert the other end into a clean container. Pour hydraulic fluid into the container, such that the end of the hose is covered. 6 Following the manufacturer's instructions, pour hydraulic fluid into the bleeding kit vessel 7 Unscrew the vehicle's fluid reservoir cap, then connect Ihe bleeding kit fluid supply hose to the reservoir. 8 Connect the pressure hose to a supply of compressed air - a spare tyre is a convenient source. Caution: Check that the pressure In the tyre does not exceed the maximum supply pressure quoted by the kit manufacturer, let soma sir escape to reduce the pressure, if necessary. Gently open the air valve and allow the air and fluid pressures to equalise. Check that there ere no teaks before proceeding. 9 Using the spanner, slacken the bleed pipe nipple until fluid and air bubbles can be seen to flow through the tube, into the container.
Maintain a steady flow until the emerging fluid la free of air bubbles; keep a watchful eye on the level of fluid in the bleeding kit vessel and the vehicle's fluid reservoir • if it Is allowed to drop too low, air may be forced into the system, defeating the object of the exercise. To refill the vessel, turn off the compressed air supply, remove the lid and pour In en appropriate quantity of clean fluid from a new container - do not re-use the fluid collected in the receiving container. Repeat as necessary until the ejected fluid is bubble-free. 10 On completion, pump the olutch pedal several times to assess its feel and travel. If firm, constant pedal resistance is not felt throughout the pedal stroke, it i6 probable that air Is still present in the system - repeat the bleeding procedure untii the pedal feel is restored. 11 Depressurise the bleeding kit and remove it from the vehicle. At this point, the fluid reservoir may be over-full; the excess should be removed using a clean pipette to reduce the level to the MAX mark. 12 Tighten the bleed pipe nipple using the spanner and remove the receiving container. Refit the protective cap. 13 On completion, assess the feel of the clutch pedal; if it exhibits any sponginess or looseness, further bleeding may be required. 14 Where removed, refit the battery and tray. 15 Finally, road test the vehicle and check the operation of the clutch system whilst changing up and down through the gsar9. whilst pulling away from a standstill and from a hill start.
5 Clutch master cylinder - & removal
and
refitting 5 S Note: This procedure applies to models
fitted
with the hydraulically-operated dutch
release
mechanism. Note: Refer to the warning at Ihe beginning
of
Section 4 regarding the hazards of
working
with hydraulic fluid.
Removal 1 Disconnect the battery negative terminal (refer lo Disconnecting the battery in the Reference Section of this manual). 2 Remove the air cleaner and air ducting as described in the relevant Part of Chapter 4. 3 For improved access on petrol engine models, remove the alternator as described In Chapter 5A. 4 Fit a brake hose clamp to the hose between the hydraulic fluid reservoir and the clutch master cylinder. Alternatively syphon ail the fluid from the reservoir. 5 Disconnect the fluid supply hose at the master cylinder, then unscrew the union nut and disconnect the hydraulic pipe from the cylinder outlet. Be prepared for some fluid loss by placing some rags beneath the master cylinder.

Clutch 6*3
6 WorWng inside the vehicle, extract the split pin and remove the washer securing the master cylinder pushrod to the clutch pedal. Dsoonnect the pushrod from the pivot. 7 Have an assistant support the master cylinder In the engine compartment, then unscrew the mounting bolts. Withdraw the master cylinder from the engine compartment, 8 II is not possible to obtain an overhaul kit from Flat however some motor factors may be abls to supply one. Follow the Instructions with the repair kit if obtained.
Refitting 9 Refit the clutch master cylinder by following ihe removal procedure In reverse, noting the following. a) Apply a
Utile
high-melting point grease to the clutch pedal pivot. b) Tighten the mounting bolts and union nut securely. cj Fit a new split pin to the pushrod. d) Where removed, refit the alternator
as
described In Chapter 5A e) On completion bleed the clutch hydraulic system as descnbed in Section
A.

7 Clutch assembly -
removal,
inspection
and
refitting
S Clutch slave cylinder-removal and refitting
Note: This procedure applies to models fitted
ivrth
the hydraulically-operated clutch release mechanism. Note: Refer to the warning at the beginning
of
Section A regarding the hazards of working
with
hydraulic fluid.
Removal 1 Remove the battery and battery tray as described in Chapter 5A. 2 Fit a brake hose clamp to tha hose leading to the clutch slave cylinder. 3 Unscrew the union nut and disconnect the hydraulic pipe from the slave cylinder. Be prepared for some fluid loss by placing rags beneath the cylinder. 4 Unscrew the mounting bolts and release the slave cylinder pushrod from the release am on the transmission, then remove the unit from the engine compartment (see Illustration). 5 It is not possible to obtain an overhaul kit from Flat however some motor factors may be able to supply one. Follow tha instructions with the repair kit if obtained.
Refitting 6 Refit the clutch slave cylinder by following the removal procedure In reverse, noting the following. a) Apply a little high-melting point grease to the tip of the slave cylinder pushrod. b) Tighten the mounting bolts and union nut securely. c) On completion bleed the dutch hydraulic system as described in Section A.

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Warning: Dust created by clutch wear and deposited on the clutch components may contain asbestos, which Is a health hazard. DO NOT blow it out with compressed air, or inhale any of it. DO NOT use petrol or petroleum-based solvents to clean off the dust. Brake system cleaner or methylated spirit should be used to flush the dust Into a suitable receptacle. After the clutch components are wiped clean with rags, dispose of the confam/nafed rags and cleaner In a sealed, marked container. Note: Although some friction materials may no longer contain asbestos, it is safest to assume that they DO. and to take precautions accordingly.
Removal 1 Unless the complete engine/transmission is to be removed from the car and separated for major overhaul (see Chapter 2D), Ihe clutch can be reached by removing the transmission as descnbed in Chapter 7A, 2 Before disturbing the clutch, use chalk or a marker pen to mark the relationship of the pressure plate assembly to the flywheel. 3 Working In a diagonal sequence, slacken the pressure plate bolts by half a turn at a time, until spring pressure Is released and the bolls can be unscrewed by hand (see Illustration). 4 Prise the pressure piate assembly off its locating dowels, and collect the friction plate, noting which way round the friction plate is fitted (see Illustration).
Inspection Note: Due to the amount of work necessary to remove and refit clutch components, It is usually considered good practice to renew the clutch friction plate, pressure plate assembly and release bearing as a matched set. even if only one of these is actually worn enough to require renewal. It Is also worth considering the renewal of the clutch components on a preventative basis if the engine and/or
6.4 Removing the clutch slave cylinder from the transmission fransmj'ss/on have been removed for some other reason. 5 Separate the pressure plate and friction plate and place them on the bench. 6 When cleaning clutch components, read first the warning at the beginning of this Section; remove dust using a clean, dry cloth, and working in a well-ventilated atmosphere. 7 Check the friction plats facings for signs Of wear, damage or oil contamination. If the friction material is cracked, burnt, scored or damaged, or if It is contaminated with oil or grease (shown by shiny black patches), the friction plate must be renewed. 8 If tho friction material Is still serviceable, check that the centre boss splines are unworn, that the torsion springs are In good condition and securely fastened, and that all the rivets are tight. If any wear or damage is found, the friction plate must be renewed. 9 If the friction material is fouled with oil, this must be duo to an oil leak from the crankshaft rear (left-hand) oil seal, from the sump-to-cytinder block joint, or from the transmission Input shaft. Renew tha soal or repair the Joint, as appropriate, before Installing the new friction plate. 10 Check tha pressure plate assembly for obvious signs of wear or damage; shake it to check for looss rivets or worn or damaged fulcrum rings, and check thai the drive straps securing the pressure plate to the cover do not show signs (such as a deep yellow or blue discoloration) of overheating. If the diaphragm spring is worn or damaged, or if its pressure is In any way suspect, the pressure plate assembly should be renewed.
7.3 Removing the clutch pressure plate bolts 7.4 Removing the clutch pressure plate and friction plate
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6*4 Clutch
7.17 Using a clutch friction plate centralising toot 11 Examine the machined beanng surfaces of the pressure plate and of the flywheel; they should be clean, completely flat, and free from scratches or scoring. If either is discoloured from excessive heat, or shows signs of cracks, it should be renewed - although minor damage of this nature can sometimes be polished away using emery paper 12 Check that the release bearing contact surface rotates smoothly and easily, with no sign of noise or roughness. Also check that the surface itself is smooth and unworn, with no signs of cracks, pitting or scoring. If there Is any doubt about its condition, the bearing must be renewed.
Refitting 13 On reassembly, onsure that the bearing surfaces of the flywheel and pressure plate are completely clean, smoolh. and tree from oil or grease. Use solvent to remove any protective grease from new components. 14 Fit the friction plate so that its spring hub assembly faces away from the flywheel; there may also be a marking showing which way round the plate Is to be refitted. 15 Refit the pressure plate assembly, aligning the marks made on dismantling (If the original pressure plate Is re-used), and locating the pressure plate on Its three
locating dowels. Fit the pressure plate bolts, but tighten them only finger-tight, so thai the friction plate can skill be moved. 16 The friction plate must now be centralised, so that when the transmission Is refitted, Its Input shaft will pass through the splines at the centre of the friction plate. 17 Centralisation can be achieved by passing a screwdriver or other long bar through the friction plate and into the holo in the crankshaft; the friction plate can then be moved around until it is centred on the crankshaft hole. Alternatively, a clutch-aligning tool can be used to eliminate the guesswork; these can be obtained from most accessory shops (see illustration). A home-made aligning tool can be fabricated from a length of metal rod or wooden dowel which fits closely Inside the crankshaft hole, and has insulating tape wound around it to match Ihe diameter of the friction plate splined hole. 18 When the friction plate is centralised, tighten tho pressure plate bolts evenly and In a diagonal sequence to the specified torque setting. 19 Apply a Ihin smear of molybdenum dlsulphide grease to the splines of the friction plate and the transmission input shaft, and also to the release bearing bore and release fork shaft. 20 Refit the transmission as described In Chapter 7A.
8 Clutch release mechanism - & removal, inspection J and refitting ^
Removal 1 Unless the complete engine/transmission is to be removed from the car and separated lor major overhaul (see Chapter 2D), the clutch release mechanism can be reached by removing the transmission as described In Chapter 7A.
2 Unhook the release bearing from the fork and slide it off Ihe guide tubo (see illustration). 3 Using circlip pliers extract the circllp Irom the top of the release fork shaft. 4 Note the position of the arm then slide it
oW
the splines. 5 Using a small drift, tap out the upper release shaft bush from the transmission casing (see illustration). 6 Lift the release shaft from Ihe lower bush then remove it Irom inside Ihe transmission casing.
7 Extract the lower bush from 1he casing.
inspection 8 Check (he release mechanism, renewing any worn or damaged parts. Carofully checH all bearing surfaces and points of contact. 9 When checking the release bearing ilsell. note that it Is often considered worthwhile to renew it as a matter of course. Check thai the contact surface rotates smoothly and easily, with no sign of roughness, and that Ihe surface itself is smooth and unworn, with no signs of cracks, pitting or sconng. If there is any doubt about Its condition, the bearing must be renewed, Refitting 10 Apply a smear of molybdenum dlsulphide grease to the shaft pivot bushes and the contact surfaces of the release fork. 11 Tap the lower bush into the casing and refit the release fork and shaft. 12 Slide the upper bush down the shaft and tap it into the casing making sure lhat the ridge engages with the cut-out. then slide the arm on the splines the correct way round. 13 Refit the circlip in the shaft groove. 14 Slide the release bearing onto the guide tube and engage it with the fork. 15 Refil the transmission as described in Chapter 7A.
8.2 Removing the release bearing from the fork and guide lube 8.5 Clutch release shaft (1) and upper shaft bush (2)

7B*2 Automatic transmission
disconnected. As the magnetic field increases, the powder sticks together, and the coupling between Ihe elements becomes Increasingly rigid. 7 Selection of reverse, neutral and forward gears is by the movement of a sliding sleeve on a hub keyed to the drive pulley shaft. In forward gear, the sleeve engages with the gear on the end of the input shaft, which is then locked to the drive pulley shaft. When reverse is selected, the sleeve engages with reverse driven gear, which is in constant mesh with an idler gear driven by transfer gears from the input shaft gear. In neutral, the sleeve Is in an intermediate position, and the
two shafts are not connected. 8 Tho drive pulley and driven pulley both consist of fixed and moving halves. The movement of ihe drive pulley halves is controlled hydraulically, while the driven pulley halves move under the influence of a spring and the tension exerted by the drivebeit. As the drive pulley opens, the driven pulley closes, and vice-versa. In this way, the transmission ratio between the two pulleys can be varied. The ratios are continuously variable between preset limits; the difference between the lowest and highest ratios available is approximately 5:1. 9 Hydraulic pressure is generated by a gear-
type pump Inside the transmission. The punp driveshaft runs inside the Input and drive pulley shafts, and Is splined to the centred the engine flywheel. This means that hydreulc pressure is only generated when the engine is running, which is why a car with this type ot transmission cannot be push- or tow-started 10 Application of hydrautic pressure to the pulley halves is via a control unit, which receives information on accelerator pedal position, transmission selector lever position, transmission ratio currently in use, and drive pulley speed. From this information, the control unit determines whether, and in which direction, lo change the pulley ratios.
1.1 a Cutaway view of the ECVT (electronic continuously variable transmission) 7 Electromagnetic dutch 3 Drive pulley 5 Metal drivebeit 7 Hydraulic controt unit 2 Gear selector sleeve A Dnven pulley 6 Final drive reduction gears

Automatic transmission 7B*3
11 When reverse gear Is selected, the control unit keeps the transmission In tow ratio, if this were not the case, it would, In theory, be possible to drive as fast In reverse as in forward gear. 12 An electronic control unit supplies the current to energise the clutch. The control unit receives signals concerning engine speed, road speed, accelerator pedal position, and gear selector position, Sensors include the following. a) Engine rpm sensor (from the Injection/ignition control unit) b) Accelerator pedal switch
c) Throttle valve position sensor d) Selector lever position sensor e) Vehicle speed sensor f) Coolant temperature sensor g) Air conditioning sensor h) Brake switch I) Torque signal
13 The final drive/differential unit Is conventional. Drive from the driven pulley is transmitted to the differential by an Intermediate reduction gear. 14 The ECVT incorporates a warning light which illuminates when a fault occurs.
Precautions 1$ Observe the following precautions to avoid damage to the automatic transmission: a) Do not attempt to start the engine by pushing or towing the car. b) If the car has to be towed for recovery, the distance must not exceed 12 miles (20
km),
and the speed must not exceed
19
mph
(30 kph).
If these conditions cannot be met, or If transmission damage is suspected, only tow the car with the front wheels clear of the ground. c) Only engage P or R when the vehicle is stationary.
1.1b Electromagnetic f Coil 2 Signal from vehicle speed sensor 3 Transmission 4 Electromagnetic powder 5 Drive shaft (driven by crankshaft) $ Transmission input shaft 7 Electromagnetic clutch housing 8 ECVT control unit
clutch control system 9 Accelerator pedal micro switch 10 Throttle
vafve
opening position potentiometer 11 Multifunction switch 12 Ignition switch
13
Air conditioning
signal
14 Engine PPM
signal
15 Accelerator pedal 16 Coolant temperature signal 17 Injection/ignition control unit 18 8attery
1.1c Hydraulic control system 3 Injection/ignition control unit 4 Air conditioner sensor
signal
6 Coolant temperature signal 7 Clutch signal 8 Engine RPM
signal
9 ECVT warning light 10 Selector lever position 11 Accelerator
pedal
switch/throttle
valve
potentiometer/torque signal 12 Brake switch 13
ECVT
control unit 14 Signal from vehicle speed sensor
15
Accelerator pedal position switch
16 Pulley ratio 17 Input shaft RPM 18 Primary oil pressure
19
Primary pulley 20 Electromagnetic clutch 21 Pressure regulating solenoid valve 22 Oil pressure control valve 23 Secondary oil pressure 24 Slip ring 25 Drive from engine 26 Oil pump 27 Vehicle speed sensor 28 Secondary pulley 29 Belt and pulley 30 Drive to drlveshafts

9*2 Braking system
2.3a Release tho locking clip ...
1 General information
The braking system is of the vacuum servo-assisted. dual-circuit hydraulic type. The arrangement of Ihe hydraulic system is such that each circuit operates one front ond ono rear brake from a tandem master cylinder. Under normal circumstances, both circuits operate In unison However, in the event of hydraulic failure in one circuit, lull braking force will still be available at two diagonally-opposite wheels. All models covered in this manual are fitted with front disc brakes and rear drum brakes. The front disc brakes are aotuated by single-piston sliding lype calipers, which ensure lhat equal pressure is applied to each brake pad. The rear drum brakes incorporate leading and trailing shoes, which are actuated by twin-piston wheel cylinders. A self-adjust mechanism is incorporated, to automatically compensate for brako shoe wear. As the brake shoe linings wear, the footbrnke operation automatically operates the adjuster mechanism, which effectively lengthens the shoe strut and repositions the brake shoes, to remove the llning-to-drum clearance. The mechanical handbrake linkage operates the brake shoos via a lever attached to the trailing brake shoe.
2.3b ... and remove the pad wear indicator wiring and brake fluid line from the suspension strut Load sensitive proportioning valves operate on the rear brake hydraulic circuits, to prevent the possibility of the rear wheels locking before the front wheels under heavy braking. Note: When servicing any part of the system, work carefully and methodically; also observe scmpulous cleanliness when overhauling any part of the hydraulic sysiem. Always renew components (in axle sets, where applicable) if In doubt about their condition, and use only genuine Fiat replacement parts, or at least those of known good quality. Note the warnings given in Safety first and at relevant points in this Chapter concerning fhe dangers of asoestos dust and hydraulic fluid.
Models with anti-lock braking system (ABS) Available as an option on certain models, the anti-lock braking system prevents skidding which not only optimises stopping distances but allows full steering control to be maintained under maximum braking. By electronically monitoring the speed of each roadwheel in relation to the other wneete, Ihe system can detect when a wheel is about to lock-up, before control is actually lost. The brake fluid pressure applied to that wheel's brake caliper is then decreased and restored (or modulated) several times a second until control
£s
regained. The system components comprise an Electronic Control Unit (ECU), four wheel speed sensors, a hydraulic unit, brake lines and dashboard mounted warning lamps.
The hydraulic unit incorporates a tandem master cylinder, a valve block which modulates the pressure in the brake hydrauli: circuits during ABS operation, an accumulator which provides a supply of highly pressursed brake fluid, a hydraulic pump to charge Ihe accumulator and an integral electronic control unit (ECU). The four wheel sensors are mounted on the wheel hubs. The ECU uses the signals produced by the sensors to calculate Ihe rotational speed of each wheel, The ECU has a self-diagnostic capability and will inhibit the operation of the ABS il a fault is detected, lighting the dashboard mounted warning lamp. The braking system will then revert lo conventional. non-ABS operation. II the nature of the laull ie not immediately obvious upon inspection, the vehicle must be taken to a Fiat dealer, who will have the diagnostic equipment
required
lo interrogate the ABS ECU electronically and pin-point the problem
2 Front brake pads - & renewal S

A


Warning: Renew BOTH sets ol front brake pads at the same
time
- NEVER renew the pads on
only
one wheel, as uneven braking may result

A


Warning: Note that the dust created by wear of the pads
may
contain asbestos, which is a health hazard. Never blow It out with compressed air, and don't inhale any of
it.
An approved filtering mask should be worn when working on the brakes. DO NOT use petrol or petroleum-based solvents to clean brake parts; use proprietary braks cleaner or methylated spirit only. 1 Firmly apply the handbrake, then jack up the front of the car and support it securely
on
axle stands (see Jacking and vehicle supporti. Remove the front roadwheeis. 2 Wording on one side of the vehicle, puth the caliper piston into its bore by pulling the caliper outwards. If necessary, press the piston back into its bore using a large G-clamp or a piston retraction tool. Keep a careful eye on the level of brake llufd in Ihe I reservoir as you do this - ensure that the
level
I does not rise above the MAX marking. 3 Whore applicable, release the locking dp and remove the pad wear indicator
wiring end
brake fluid line from the bracket at Ihe
base of
the suspension strut (see illustrations).
Petrol models without ABS 4 Remove the locking clip and exlracl the lower guide pin from the caliper (see illustrations) 5 Pivot the caliper body upwards and support In position with a length of wire or a cabie-fc. Avoid straining the hydraulic hose.
2,4a Remove the locking clip ... 2.4b ... and extract the lower guide pin from the caliper (petrol models without ABS)

Braking system 9®3
2.6a Unscrew the upper...
Petrol models with ABS and diesel models 6 Unscrew the upper and lower caliper guide cin bolts, using a slim open-ended spanner to counterhold the head of the guide pin (see illustrations). Discard the guide pin bolts -new items must be fitted on reassembly. 7 Lift the caliper from the hub/disc assembly (see illustration). Suspend it from a suitable point on the suspension using a length of wire or 8 cable-tie, to avoid straining the hydraulic hose.
All models Caution: Do not depress the brake pedal until the caliper is refitted, or the piston will
be
pushed out of Its bore. 8 Withdraw the brake pads from the caliper bracket (see illustrations). 9 Measure the thickness of each brake pad's foclion material. If either pad is worn at any point to the specified minimum thickness or less, all four pads must be renewed. Also, the pads should be renewed if any are fouled with oil or grease; there is no satisfactory way of degreasing friction material, once contaminated. If any of the brake pads are worn unevenly, or are fouled with oil or grease, trace and rectify the cause before reassembly.

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Warning: Do not be tempted to swap brake pads over to compensate for uneven wear. 10 if the brake pads are still serviceable, carefully clean them using a clean, fine wire brush or similar and brake cleaning fluid. Pay particular attention to the sides and back of the metal backing. Where applicable, clean out the grooves in the friction material, and pick out any large embedded panicles of dirt
or
debris. 11 Clean the surfaces of the brake pad contact points In the caliper body and caliper mounting bracket. 12 Prior to fitting the pads, check that the giide pins can slide freely in the caliper body, and check that the rubber guide pin gaiters
are
undamaged. Brush the dust and din from
the
caliper and piston, but do not inhale it. as
4 may
contain asbestos. 13 Inspect the dust seal and the area around Ihe piston for signs of damage, corrosion or
models with ABS and diesel models)
brake fluid leaks. If evident, refer to Section 3 and overhaul the caliper assembly. 14 If new brake pads are to be fitted, the caliper piston must be pushed back into the cylinder, to allow for the extra depth of the friction material. Either use a G-clamp or similar tool, or use suitable pieces of wood as levers. Provided that the master cylinder reservoir has not oeen overfilled with hydraulic fluid, there should be no spillage, but keep a careful watch on the fluid level while retracting the piston. If the fluid level rises above the MAX level line at any time, the surplus should be siphoned off. A Warning: Do not syphon the fluid by mouth, as it is poisonous; use a syringe or an old poultry baster. 15 Apply a little high temperature brake grease to the contact surfaces of the pad backing plates: take great care not to allow any grease onto the pad friction linings. Similarly, apply brake grease to the pad contact points on the caliper bracket - again take care not to apply excess grease, which may contaminate the pads. 16 Place the brake pads in position on the caliper bracket, with the friction material facing the surfaces of the brake disc. Feed the wear indicator cable through the caliper body aperture.
Petrol models without ABS 17 Pivot the caliper body down over the brake pads, then refit the guide pin and clip.
2.7 Lift the caliper from the hub/disc assembly
Petrol models with ABS and diesel models 18 Fit the caliper body in position on the caliper bracket, then fit the new guide pin bolts and tighten them to the specified torque.
AH models 19 Check that the caliper body can slide freely on the guide pins. Ensure that the flexible hydraulic hose is not twisted or kinked In any way. Turn the steering from lock to lock and check that the hose does not chafe against the suspension or steering gear. 20 Where applicable, reconnect the pad wear indicator wiring and press it into the retaining clips on the suspension. 21 Repeat the above procedure on the remaining front caliper. 22 With both sets of front brake pads fitted, depress the brake pedal repeatedly until the pads are pressed into firm contact with the brake disc, and normal pedal pressure is restored. Any sponginess felt when depressing the pedal is most probably due to air trapped inside the hydraulic system - refer to Section 11 and bleed the braking system before progressing any further. 23 Refit the roadwheels. and lower the vehicle to the ground. 24 Check the hydraulic fluid level as described in Weekly checks. 25 Check the operation of the braking system thoroughly,
2.8a Withdraw the outboard... 2.8b ... and inboard brake pads from the caliper bracket

9*4 Braking system
3.5 Unscrew the caliper upper guide pin bolt and remove tho caliper body (torn the bracket
3 Front brake caliper -removal, overhaul and refitting ^

A


Warning: Before starting work, refer to the warnings at the beginning of Sections 2 and 11 concerning the dangers of handling asbestos dust and hydraulic fluid.
Removal 1 Chock the rear wheels, apply the handbrake, then |ack up the front of the vehicle and support it on axle stands {see Jacking and vehicle support). Remove the appropriate front roadwheel. 2 Remove the brake pads as described In Section 2. 3 To minimise fluid loss dunng the following operations, remove the master cylinder reservoir cap. then
tig hi en
it down onto a piece of polythene, to obtain an airtight seat. Alternatively, use a brake hose clamp to seal off the flexible hose running to the caliper.

A


Warning: Do not use an ordinary G-clamp or mole grips for this purpose, as these can easily damage the hydraulic hose Internally, possibly leading to failure. 4 Clean the area surrounding the brake hose union, then slacken ft using a ring spanner. It won't be possible to separate the union completely without twisting the hose ai this slage.
3.7 Unscrew the two securing bolts (arrowed) and remove the caliper mounting bracket from the hub carrier
5 On petrol models without ABS, unscrew the caliper upper guide pin bolt using a hex bit or Allen key and remove the caliper body from the bracket (see illustration). 6 Hold the brake hose and rotate the caliper to unscrew the hose union from the caliper body. Cover the open ends of the union and the caliper fluid inlet, to prevent dirt Ingress. Alternatively, Ihe flexible brake hose may be separated from the rigid brake pipe, at the bracket mounted on the Inner wheel arch. 7 If desired, the caliper mounting bracket can be removed from the hub carrier after unscrewing ihe two securing bolts (see Illustration) but note that locking compound must be applied to the bolt threads on refitting.
Overhaul Note: Before commencing work, ensure that the appropriate caliper overhaul kit
Ss
obtained. 8 With the caliper on the bench, wipe away all (races of dust and dirt, but avoid inhaling the dust, as It
Is
a health hazard. 9 Place a small block of wood between the caliper body and tho piston, to act as padding. Remove the piston by applying a Jet of low pressure compressed air (such as that pioduced by a tyre foot pump) to the fluid inlel port.

A


Warning: Protect your hands and eyes when using compressed air In this manner • brake fluid moy be ejected under pressure when the pisfon pops out of Its bore. 10 Peel the dusi seal from the piston, then use a soft, blunt instrument (ie not a screwdriver) to extract the piston seal from the caliper bore. 11 Thoroughly clean all components, U9tng only methylated spint or clean hydraulic fluid, Never use mineral-based solvents such as petrol or paraffin, which will attack Ihe hydraulic system rubber components. 12 The caliper piston seal, the dust seal and the bleed nipple dust cap, a/e oniy available as part of a seat kit. Since the manufacturers recommend that the piston seal and dust seal are renewed whenever they are disturbed, all of these components should be discarded on disassembly and new ones fitted on reassembly as a matter of course. 13 Carefully examine all parts of the caliper assembly, looking for signs of wear or damage. In particular, the cylinder bore and piston must be free from any signs of scratches, corrosion or wear. If there is any doubt about ihe condition of any part of the caliper, the relevant port should be renewed Note that the piston surface is plated, and must not be polished with emery or similar abrasives to remove corrosion or scratches. In addition, the pistons are matched to the caliper bores and can only be renewed as a part of a complete caliper assembly. 14 Check that the threads in the caliper body and the mounting bracket are in good condition, Check that both guide pins are
undamaged, and (when cleaned) a reasons^' tight sliding fit In the mounting bracket bores. 15 UsecompressedairtOblow clear the IkuJ passages. Warning: Wear eye protection when using compressed
air.
16 Before commencing reassembly, en$vr« that all components are spotlessly-clean
and
dry. 17 Soak the new piston seal m clean hydraulic fluid, and fit it to the groove
In
tftt cylinder bore, using your fingers only (rift tools) to manipulate it into place. 18 Fit the new dust seal inner ftp to tne cylinder groove, smear clean hydraulic Hud over the piston and caliper cylinder
bore, and
twist ihe pfaton into the dust seal. Press tne piston squarely Into the cylinder, then sildt the dust seal outer lip to tho groove in we piston
Refitting 19 Where applicable, refit the caliper mounting bracket to thB hub earner. Ccaitto threads ol the mounting bolts with locking compound, then tighten them to the speclfed torque. 20 Hold the brake hose and rotate Ihe calip* to screw the hose union back Into the caliper body. 21 On petrol models without ABS, place the caliper In position on the bracket and tighter the caliper upper guide pin bolt to the specified torque. 22 Relit ihe brake pads as described m Section 2. 23 On all models, tighten the brake hose-to-callper union securely. 24 Check that the caliper slides smoothly
on
its guide pins. 25 Where applicable, remove the polytbste from the master oyhnder rasarvoir cap, or remove tho clomp from the fluid hose, ai applicable. 26 Bleed tho hydraulic fluid circuit as desenbed m Section 11. Note that if rootMf part of the system has been disturbed, < should only be necessary to bleed tha relevant front circuit, 27 Depress the brake pedal repeatedly to bring ihe pads into contact with ihe brake disc, and ensure that normal pedal
pressure is
restored. 28 Refit the roadwheel, and lower tha veti'cfc lo ihe ground.
4 Brake disc -
inspection,
removal
and
refitting
Inspection 1 Firmly apply the handbrake, then jaefcup the front of the car and support It securely
oft
axle stands (see Jacking and vehicle
support1,.
Remove the front roadwhesls.
expert22 f
a http://rutracker.org

9*8 Braking system
6 Carefully examine the Inside of tho drum. Light scoring of the friction surface is normal, but if heavy scoring Is found, the drum must be renewed. 7 It is usual to find a lip on the dmm's inboard edge which consists of a mixture of rust and brake dust: this should be carefully scraped away, to leave a smooth surface which can be polished with fine (120 to 150-grade) emery paper. If, however, the tip is due to the friction surface being recessed by excessive wear, then the drum must be renewed. 6 If the drum Is thought to be excessively worn, or oval, its internal diameter must be measured at several points using an internal micrometer. Take measurements In pairs, the second at right-angles to the first, and compare the two, to check for signs of ovality. Provided that it does not enlarge the dium to beyond the specified maximum diameter, it may be possible to have the drum refinished by skimming or grinding; if this is not possible, Ihe drums on both sides must be renewed. Note that if the drum is to be skimmed, BOTH drums must be refinished. to maintain a consistent Internal diameter on both sides.
Refitting 9 II a new brake drum is to be Installed, use a suitable solvent to remove any preservative coating thai may have been applied to its internal fnction surfaces. Note that it may also be necessary to shorten the adjuster strut length, by rotating the sedated strut wheel, lo allow Ihe drum lo poss over the brake shoes • see Section S for details. 10 II tho original dfum is being refitted, align the marks made on the drum and hub before removal, then lit the drum over the hub. Refit the locating studs and tighten them to the specified torque. 11 Depress the footbrake repeatedly to expand the brake shoes against the drum, and ensure that normal pedal pressure Is restored. 12 Check and if necessary adjust the handbrake cable as described In Section 9. 13 Refit tho roadwheels, and lower the vehicle to the ground.
7 Rear wheel cylinder -removal, overhaul and refitting jS

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Warning: Before starting work, refer to the warnings at tho beginning of Sections 2 and 11 concerning the dangers ot handling asbestos dust and hydraulic fluid.
Removal 1 Remove the brake drum fsee Section 6). 2 Remove the brake shoes (see Section 5). 3 To minimise fluid loss during the following operations, remove the master cylinder reservoir cap. then tighten it down onto a piece of polythene, lo obtain an airtight seal.
the hydraulic pipe from the rear of the wheel cylinder 4 Clean the brake backplate around Ihe wheel cylinder mounting boits and the hydraulic pipe union, then unscrew the union nut and disconnect Ihe hydraulic pipe (see illustration). Cover the open ends of the pipe and the master cylinder to prevent dirt ingress, 5 Remove the securing bolts, then withdraw the wheel cylinder from the backplate (soe Illustration).
Overhaul Note: Before commencing woric, ensure that the appropriate wheel cylinder overhaul kit is obtained. 6 Clean tho assembly thoroughly, using only methylated spirit or clean brake fluid, 7 Peel off both rubber dust covers, then use paint or similar to mark one ot the pistons so that the pistons are not interchanged on reassembly. 8 Withdraw both pistons and tho spring. 9 Discard the rubber piston cups and the dust covers. These components should be renewed as a matter of course, and are available 3s part of an overhaul kit, which also Includes the bleed nipple dust cap. 10 Check the condition of the cylinder bore and the pistons - the surfaces must be perfect and free from scratches, scoring and corrosion, It is advisable to renew the complete wheel cylinder if there is any doubt as to the condition ot the cylinder bore or pistons. 11 Ensure thai all components are clean and dry. The pistons, spring and cups should be
8.4 Location of brake tight switch-LHD model shown
withdraw the wheel cylinder from the backplate fitted wet, using hydraulic fluid as a lubricant • soak them in clean fluid before installation. 12 Fit the cups to the pistons, ensuring that they are the correct way round. Use only your fingers (no tools) to manipulate the cups into position. 13 Fit the first piston to the cylinder, taking care not to distort the cup. If the original pistons are being re-used, ihe marks
made on
dismantling should be used to ensure that the pistons are refitted to their original bores, 14 Refit the spring and the second pfston. 15 Apply a smear of rubber grease to Ihe exposed end of each piston and to the dust cover sealing lips, then fit Ihe dust covers to each end of the wheel cylinder.
Refitting 16 Refitting is a reversal of removal, bearirg in mind the following points: a) Tighten the mounting bolts to the specified torque. b) Refit the brake shoes as desenbod
In
Section 5. and refit the brake drum
as
described in Section 6. c) Before refitting the roadwheel
and
lowering the vehicle to the ground, remove the polythene from the fluid reservoir, and bleed the hydraulic
system
as described in Section f
1.
Note that if
nc
other part of the system has been disturbed, it should only bo necessary
to
bleed the relevant rear circuit.
8 Stop-light switch • & adjustment, removal J? and refitting
Adjustment 1 The switch plunger operates on a ratchet 2 If adjustment Is required, pull the plunge fully out - (he 9witch then sell-adjusts as the brake pedal Is applied and released.
Removal 3 Ensure that the ignition Is switched to OfF. 4 For Improved access, remove the driver's side lower facia panel, as described in Chapter 11 (see Illustration). 5 Disconnect the wiring plug from the switch.

9*10 Braking system
10.6 Disconnect the relevant handbrake inner cable (arrowed) from the draw bar 6 Working inside ihe vehicle, remove Ihe screws and lift off the handbrake lever trim panel (refer to Section 9 for more detail). At the base of the handbrake lever, full/ slacken off the handbrake adjusting screw and locknut, to remove oil tension from the cable draw bar, then disconnect the relevant handbrake inner cable from the cable draw bar (see illustration) 7 Release the cable grommet from tho floor-pan, then withdraw the cable from the vehicle.
Refitting 8 Refitting Is a reversal of removal, bearing in mind the following points: a) Ensure that the cables are securely fastened In the clips on the floorpan beetshield and lower suspension a/m. b) On completion, check the handbrake adiustment, as described in Section 9.
11 Hydraulic system -bleeding

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Warning: Hydraulic fluid is poisonous; wash off immediately and thoroughly In the case ot skin contact, and seek immediate medical advice if any fluid is swallowed, or gets into the eyes. Certain types of hydraulic fluid are Inflammable, and may ignite when allowed into contact with hot components. When servicing any hydraulic system, it Is safest to assume that the fluid IS inflammable, and to take precautions
11.17 Bleeding a rear brake line
against the risk of fire as though it is petrol that Is being handled. Hydraulic fluid is also an effective paint stripper, and will attack plastics; If any is spilt, It should be washed off immediately, using copious quantities of fresh water. Finally, it Is hygroscopic (it absorbs moisture from the air) • old fluid may be contaminated and unfit tor further use. Whan topping-up or renewing the fluid, always use the recommended type, and ensure that It comes from a freshly-opened sealed container.
General 1 The correct operation of any hydraulic system is only possible after removing all air from the components and circuit; and this Is achieved by bleeding the syslem. 2 During the bleeding procedure, add only clean, unused hydraulic fluid of the recommended type; never re-use fluid that has already been bled from the system. Ensure that sufficient fluid is available before starting work. 3 If there is any possibility of incorrect fluid being already in the system, the brake com-ponents and circuit must be Flushed completely with uncontamlnated, correct fluid, and new seals should be fitted throughout the system. 4 If hydraulic fluid has been lost from the system, or air has ontered because of a leak, ensure that the fault is cured before proceeding further. 5 Park Ihe vehicle on level ground, switch off the engine and select first or reverse gear (or P), then chock the wheels and release the handbrake. 6 Cheek that all pipes and hoses are secure, unions tight and bleed screws closed. Remove Ihe dust caps (whore applicable), and clean any dirt from around the bleed screws. 7 Unscrew the master cylinder reservoir cap, and top Ihe master cylinder reservoir up to the MAX level line; refit the cap loosely. Rememoer to maintain the fluid level at least above the MIN level line throughout the procedure, otherwise there is a risk of further air entering the syslem. 8 There are a number of one-man. do-It-yourself brake bleeding kits currently available from motor accessory shops. It is recommended that one of these kits is used whenever possible, as they greatly simplify the bleeding operation, and also reduce the risk of expelled air and fluid being drawn back into the system. If such a kit is not available, the basic (two-man) method must be used, which is described in detail below. 9 If a kit Is to be used, prepare the vehicle as described previously, and follow the kit manufacturer's instructions, as Ihe procedure may vary slightly according to the type being used; generally, they are as outlined below in the relevant sub-section. 10 Whichever method is used, the same sequence must be followed (paragraphs 11 and 12) to ensure Ihe removal of all air from the system.
Bleeding sequence 11 If Ihe system has been only
partial!?
disconnected, and suitable precautions wwe taken to minimise fluid loss, it should be necessary to bteod only that part of the system (le the primary or secondary circuit). 12 If the complete system Is to be bled, then It should be done working in the following sequence: a) Left-hand rear wheel b) Right-hand front wheel. c) Right-hand rear wheel. d) Left-hand front wheel. Note: When bleeding the rear brakes
on a
vehicle ritled with load proportioning valves: i the rear of the vehicle has been jacked
up to
allow access to ihe brake wheel cylinder,
tha
rear suspension must be compressed
(eg
raising the beam axle with a trolley
jack) so
that the load proportioning valves
remain open
throughout the bleeding process.
Bleeding -basic (two~man) method 13 Collect a clean glass jar, a suitable length of plastic or rubber tubing which Is a light fit over the bleed screw, end a ring spanner lo
Rt
the screw. The help of an assistant will also tie required. 14 Remove the dust cap from the first screw In the sequence if not already done. Fit a suitable spanner and tube to the screw, place the other end of Ihe tube In the jar. and
pour in
sufficient fluid to cover the end of the tube. 15 Ensure that the master cylinder reservoir fluid level is maintained at least above the
MIN
level line throughout the procedure. 16 Have the assistant fully depress the brefce pedal several times to build up pressure, then maintain it on the final downstroke. 17 While pedal pressure is maintained, unscrew ihe bleed screw (approximately one turn) and allow the compressed fluid and orto flow into the
Jar,
The assistant should maintah pedal pressure, following the pedal down to the floor if necessary, and should not rrtaase Ihe pedal until instructed to do so. When ihe flow stops, tighten the bleed screw again, have the assistant retease the pedal sfowty, and recheck the reservoir fluid level (see Illustration). 18 Repeat Ihe steps given in paragraphs 16 end 17 until the fluid emerging from the bled screw is free from air bubbles. If Ihe master cylinder has been drained and refilled,
and
at Is being bled from the first screw In the sequence, allow approximately five seconds between cycles for the master cylinder passages to refill. 19 When no more air bubbles appear, tighter, the bleed screw securely, remove Ihe tube arc spanner, and refit the dust cap (where applicable). Do not overtighten the bleed sew. 20 Repeat the procedure on tho remaining screws In the sequence, until ail air is removed from the system, and the brake pedal feels firm again.