weight FIAT PUNTO 1996 176 / 1.G User Guide
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Page 144 of 225

4D«1
Chapter 4 Part D:
Exhaust and emission control systems
Contents
Catalytic converter - general Information and precautions 7 Crankcase emission system • general information 3 Evaporative loss emission control system • information and component renewal 2
Degrees of difficulty
Exhaust manifold - removal and refitting 5 Exhaust system - general information and component renewal .... 6 General information 1 Lambda oxygen sensor - removal and refitting 4
Easy, suitable
tor novice with fittie ^
1 experience
Fairly easy, suitable for beginner with ^ some experience ^
Fairiy dfficult, lb suitable for competent ^ DIY mechanic ^
Difficult, suitable for experienced DIY ^ mechanic
Very difficult, ^ suitable far expert DIY or professional
Specifications
Torque wrench settings Exhaust down pipe to manifold Exhaust manifold Exhaust system mounting Exhaust to catalytic converter: M8 M10x1.25
Nm Ibfft 24 18 24 18 27 20
24 18 40 30 53 39
1 General information
Emission control systems All petrol engine models use unleaded petrol and are controlled by engine management systems that are 'tuned' to give the best compromise between driveability. luel consumption and exhaust emission production. In addition, a number of systems are fitted that help to minimise other harmful emissions: a crankcase emission-control system (petrol models only) that reduces the release of pollutants from the crankcase, an evaporative loss emission control system (petrol models only) to reduce the release of hydrocarbons from the fuel tank, a catalytic converter (petrol and diesel models) to reduce exhaust gas pollutants, and an Exhaust Gas Recirculation (EGR) system (turbo diesel models only) to reduce exhaust emissions. Crankcase emission control To reduce the emission of unburned hydrocarbons from the crankcase Into the atmosphere, the engine is sealed and the blow-by gases and oil vapour are drawn from inside the crankcase, through a flame trap.
into the inlet tract to be burned by the engine during normal combustion. Under conditions of high manifold depression (idling, deceleration) the gases will by sucked positively out of the crankcase. Under conditions of low manifold depression (acceleration, full-throttle running) ihe gases are forced out of the crankcase by the (relatively) higher crankcase pressure: if the engine is worn, the raised crankcase pressure (due to increased blow-by) will cause some of the flow to return under all manifold conditions. Exhaust emission control -petrol models To minimise the amount of pollutants which escape Into the atmosphere, a catalytic converter is fitted In the exhaust system. The fuel system is of the closed-loop type, in which a Lambda (or oxygen) sensor In the exhaust system provides the engine management system ECU with constant feedback, enabling the ECU to adjust the air/fuel mixture to optimise combustion. The Lambda sensor has a heating element built-in that Is controlled by the ECU through the Lambda sensor relay to quickly bring the sensor's tip to Its optimum operating temperature. The sensor's tip Is sensitive to oxygen and relays a voltage signal to the ECU
that varies according on the amount of oxygen In the exhaust gas. If the inlet air/fuel mixture is too rich, the exhaust gases are low in oxygen so the sensor sends a low-voltage signal, the voltage rising as the mixture weakens and the amount of oxygen rises In the exhaust gases. Peak conversion efficiency of all major pollutants occurs if the inlet air/fuel mixture Is maintained at the chemlcally-con*ect ratio for the complete combustion of petrol of 14.7 parts (by weight) of air to
1
part of fuel (the stoichiometric ratio). The sensor output voltage alters in a large step at this point, the ECU using the signal change as a reference point and correcting the Inlet air/fuel mixture accordingly by altering the fuel Injector pulse width. Exhaust emission control -diesel models An oxidation catalyst is fitted in the exhaust system of all diesel engine models. This has the effect of removing a large proportion of the gaseous hydrocarbons, carbon monoxide and particulates present in the exhaust gas. An Exhaust Gas Recirculation (EGR) system Is fitted to all turbo diesel engine models. This reduces the level of nitrogen oxides produced during combustion by Introducing a proportion of the exhaust gas back into the inlet manifold, under certain engine operating
Page 164 of 225

Manual transmission 7A*3
3,8 Unscrew the nut and disconnect the gear selector rod from the lever on the transmission unscrew the locknut and adjusting nut from the end of the clutch cable and disconnect the cable from the transmission. Recover the damper block. On models with a hydraulically operated clutch, unscrew the mounting bolts, release the slave cylinder pushrod from the re&ase arm on the transmission, then position the cylinder to one side.
7 Unscrew and remove the reverse gear Inhibiting device from the transmission. Tie the cable to one side out of the way. 8 Unscrew the nut and disconnect the gear selector rod from the lever on the transmission (see illustration). 9 Pull out the clip then disconnect the gear engagement cable from the control lever and release the cable from the mounting bracket (see illustrations). 10 Unscrew and remove the two upper transmisslon-to-englne mounting bolts. Unscrew the single bolt securing the starter motor to the transmission. 11 Remove the air cleaner and air ducting with reference to Chapter 4A or 4B. This Is necessary In order to fit the engine hoist 12 On 5-speed transmissions, trace the wiring back from the electronic speedometer sensor and disconnect the connector located on the left-hand side of the engine (see illustration). 13 On 6-speed transmissions, unscrew the knurled nut and disconnect the speedometer cable from the top of the final drive housing. 14 Support the weight of the engine using a hoist attached to the engine lifting eyes, or alternatively use a trolley jack and block of wood beneath Ihe engine. 15 Unscrew the Lambda/oxygen sensor from the exhaust downpipe and position It In a safe place to prevent damage. 16 Unscrew the nuts securing the downpipe to the exhaust manifold, then lower It and support on an axle stand. Recover the gasket. 17 Unbolt the support bracket from the engine and transmission. Recover the spacer plate. 18 Unbolt and remove the transmission lower cover, 19 Unscrew the remaining starter motor mounting bolts and support tho starter motor to one side. 20 Loosen and remove the clips securing the left- and right-hand driveshaft gaiters to the transmission output shafts.
3.9a Remove the clip to release the gear engagement cable 21 Unscrew and remove the boils securing the left-hand swivel hub assembly to the front suspension strut, then separate the components and support the swivel hub on an axle stand. 22 Move the swivel hub assembly outwards and disconnect the inner end of the dnveshaft from the transmission output shaft. Support the shaft away from the transmission to prevent damage to the garters. 23 Working beneath the vehicle, unscrew the botts securing the rear engine mounting to the underbody then unscrew the bolts securing the mounting to the transmission and withdraw the mounting assembly from under the vehicle. 24 Unscrew the bolts securing the left-hand engine/transmission mounting to Ihe body then unscrew the bolts from the transmission and remove the mounting. 25 Support the woight of the transmission on a trolley jack then unscrew the remaining nut and bolt from the belihousing and pull the transmission away from the engine. Lower it and remove from under the vehicle. A Warning: Support the trans-mission to ensure that it remains steady on the jack head. Keep the transmission levet until the Input shaft Is fully withdrawn from the clutch friction plate. Refitting
26 Refitting is a reversal of the removal procedure, but note the following points. a) Apply a smear of high-melting-point grease to the clutch friction plate splines; take care to avoid contaminating the friction surfaces.
3.12 Electronic speedometer sensor fitted to 5-speed transmissions
3.9b Removing the gear engagement cable from the mounting bracket b) Tighten all bolts to Ihe specified torque. c) Fit new clips to secure the driveshaft gaiters to the transmission output shafts. d) Adjust the clutch cable (where applicable) as described In Chapter 6.
Diesel models
Removal 27 Seloct a solid, level surface to park the vehicle upon. Give yourself enough space to move around it easily. Apply the handbrake then jack up the front of tho vehicle and support on axlo stands (see Jacking and vehicle support). Remove both front wheels. 28 Unbolt the relay support then remove the batlery and mounting tray as described in Chapter 5A. 29 On models with a cable operated clutch, unscrew the locknut and adjusting nut from the end of the clutch cable and disconnect the cable from the transmission. Recover the damper block. On models with a hydraulically operated clutch, unscrew the mounting botts. release the slave cylinder pushrod from the release arm on the transmission, then position the cylinder to one side, 30 Unscrew the nut and disconnect the gear selector rod from the lever on the transmission. 31 Disconnect the gear engagement cable from the control lever then slide out the clip and release the cable from the mounting bracket. 32 Unbolt the electronic rev counter sensor from the upper rear of the belihousing and position it to one side (see illustration).
3.32 Electronic rev counter sensor located in the upper rear of the belihousing
Page 165 of 225

7A«4 Manual transmission
33 Remove lha air cleaner front section and air ducting with reference to Chapter 4C. Also disconnect the injection pump vacuum pipe from the clips on the left-hand end of the cylinder head. This work is necessary in order to fit the engine hoist 34 Support the weight of the engine using a hoist attached to the engine lifting eyes, or alternatively use a trolley Jack and block of wood beneath the engine. 35 Unscrew the nuts securing the downpipe to the exhaust manifold, then lower it and support on an axle stand. Recover the gasket. 36 Unscrew the starter motor mounting bolts and support the starter motor to one side. 37 Disconnect the wiring from the reversing light switch on the front of the transmission. 38 Unscrew the nut and disconnect the earth cable from its stud. 39 Trace the wiring back from the electronic speedometer sensor and disconnect the connector located on the left-hand side ot the engine. If a mechanical speedometer Is fitted unscrew the knurled collar and disconnect the cabte from the transmission. 40 Unbolt and remove the transmission lower cover. 41 Using an Allen key unscrew the bolts securing the inner end of the left-hand driveshaft to the transmission flange. Remove the bolts and recover the spacer plates. Support the driveshaft on an axle stand. 42 Unscrew and remove the bolts securing the left-hand swivel hub assembly to the front suspension strut, then separate the components and support the swivel hub on an axle stand. 43 Move the swrvel hub assembly outwards and support the driveshaft away from Ihe transmission. 44 Using an Allen key unscrew the bolts securing the Inner end of the right-hand driveshaft to the intermediate shaft flange. Remove the bolts and recover the spacer plates. Support the driveshaft on an axle stand. 45 Remove the intermediate driveshaft with reference to Chapter 8. 46 Working beneath the vehicle, unscrew the bolts securing the rear engine mounting to the underbody then unscrew the bolts securing the mounting to the transmission and withdraw the mounting assembly from under the vehicle.
47 Unscrew the bolts securing the left-hand engine/transmission mounting to the body then unscrew Ihe bolts from the transmission and remove the mounting. 48 Support the weight of the transmission on a trolley jack then unscrew the remaining nut and bolts from the bellhousing and pull the transmission away from the engine.
A
Warning: Support the trans-mission to ensure that It remains steady o/i the jack head. Keep the transmission level until the Input shaft
1$
fully withdrawn from the clutch friction plate.
Refitting 48 Refitting is a reversal of the removal procedure, but note the following points. a) Appiy a smear* of high-meiting-point grease to the clutch friction piate splines; take care to avoid contaminating the friction surfaces. b) Tighten all bolts to the specified torque. c) Fit new clips to secure the driveshaft gaiters to the transmission output shafts. d) Adjust the clutch cable (where applicable) as described In Chapter 6.
4 Manual transmission overhaul -general Infomtatlon
Overhauling a manual transmission is a difficult and Involved Job for the DIY home mechanic. In addition to dismantling and reassembling many small parts, clearances must be precisely measured and, if necessary, changed by selecting shims and spacers. Internal transmission components are also often difficult to obtain, and in many Instances, extremely expensive. Because of this, If the transmission develops a fault or becomes noisy. Ihe best course of action is to have the unit overhauled by a specialist repairer, or to obtain an exchange reconditioned unit. Nevertheless, it is not impossible for the more experienced mechanic to overhaul the transmission, provided the special tools are available, and the Job is done in a deliberate step-by-step manner, so that nothing is overlooked.
The tools necessary for an overhaul include internal and external clrclip pliers, bearing pullers, a slide hammer, a sat of pin punches, a dial test Indicator, and possibly a hydraulic press. In addition, a large, sturdy workbench 8od a vice will be required. During dismantling o1 the transmission, make careful notes of how each component
1$
fitted, to make reassembly easier and more accurate. Before dismantling the transmission, it will help if you have some idea what area is malfunctioning. Certain problems can be closely related to specific areas In the transmission, which can make component examination and replacement easier. Refer to the Fault Finding Section at the end of this manual for more Information.
5 Reversing light switch -testing, removal and refitting ||
Testing 1 The reversing light circuit is controlled by a plunger-type switch screwed into the front of the transmission casing. If a fault develops, first ensure that Ihe circuit fuse has not blown. 2 To test the switch, disconnect the wiring connector, and use a multimeter (set to the resistance function) or a battery-and-bulb test circuit to check that there is continuity between the switch terminals only when reverse gear is selected. If this is not the case, and there are no obvious breaks or other damage to the wires, the switch is faulty, and must be renewed.
Removal 3 Access to the reversing light switch Is best achieved from under the vehicle. Apply the handbrake then jack up Ihe front of the vehicle and support on axle stands (see Jacking and vehicle support). 4 Disconnect the wiring connector, then unscrew It from the transmission casing.
Refitting 5 Refit the switch and tighten securely. 6 Reconnect the wiring then lower the vehicle to the ground.
Page 169 of 225

7B*4 Automatic transmission
2 Automatic transmission - ^ removal and refitting St
Removal 1 Select a solid, level surface to park the vehicle upon. Give yourself enough space to move around it easily. Apply the handbrake then jack up the front of the vehicle and support on axle stands (see Jacking and vehicle support). Remove both front wheels, 2 Remove the battery and mounting tray as described In Chapter 5A. 3 Remove the air cleaner and air inlet duct as described In Chapter 4A. 4 Disconnect the kickdown cable at the sector on the throttle housing and detach It from the mounting on the camshaft cover. Also release the cable from the support on the left-hand end of the cylinder head. 5 Disconnect the wiring connectors on the transmission. 6 Disconnect the fluid inlet and outlet Unas from the heat exchanger on top of the transmission. 7 Pull the fluid level dipstick from Its tube on the front of the transmission and tape over the top of the tube to prevent dirt entry. 8 Unscrew and remove the retaining pin and disconnect the speed selector cable from the top of the transmission. 9 Unscrew the upper bolt securing the starter motor to the transmission. 10 Unscrew the upper bolts securing the transmission to the engine. 11 Support the weight of the engine using a hoist attached to the engine lifting eyes, or alternatively UBO a trolley jack and block of wood beneath the engine, 12 Remove the screws and remove the front wheel arch liner from under the left-hand wheel arch. 13 Unscrew the nut securing the earth cablo to the transmission. 14 Using a punch drive out the roll pins securing both driveshafts to the final drive output shafts. 15 Unscrew and remove the bolts securing the left-hand swivel hub assembly to the front suspension strut, then separate the components and support the swivel hub on an axle stand. 16 Move the swivel hub assembly outwards and slide the inner end of the driveshaft from the splines on the transmission output shaft. Support the shaft away from the transmission to prevent damage to the gaiters. 17 Unscrew the lambdafoxygen sensor from the exhaust downpipe and position it In a safe place to prevent damage. 18 Unscrew ihe nuts securing the downpipe to Ihe exhaust manifold, then lower It and suppon on an axle stand. Recover the gasket. 19 Unscrew the knurled nut and disconnect the speedometer cable from the top of the final drive housing.
3-2 Locking the flywheel when removing the electromagnetic clutch 20 Unscrew the remaining bolt securing the staner motor to the transmission 21 Unbolt and remove Ihe lower flywheel cover from the transmission. 22 Working beneath the vehicle, unscrew the bolts securing the rear engine mounting to the underbody then unscrew the bolts securing the mounting lo the transmission and withdraw the mounting assembly from under the vehicle. 23 Unscrew the bolts securing the left-hand engine/transmission mounting to the body thon unscrew the bolts from the transmission and remove the mounting. 24 Support the weight of the transmission on a trolley jack then unscrew the remaining nut and bolt from the bellhouslng and pull the transmission away from the engine. Lower it and remove from under the vehicle.
A
Warning: Support the transmission to ensure that It remains steady on the Jack head. Keep the transmission level until the Input shaft and pump shaft are fully withdrawn from the electromagnetic clutch housing.
Refitting 25 Refitting is a reversal of the removal procedure, but note the following points. a} Apply a smear of high-melting-point grease to the splines of the transmission input shaft and oil pump driveshaft.
3.6 Checking the resistance of the clutch windings 1 Slip rings
0) Tighten all nuts and bolts to the
specified
torque, where given, c) Renew both driveshaft roll pins.
3 Electro-magnetic clutch • & removal, inspection 5. and refitting ^
Removal 1 Remove Ihe transmission as described n Section 2. 2 Turn the flywheel so that two of the lour mounting bolts are accessible, Hold tha flywheel stationary then unscrew Ihe tvrt bolts. To hold the flywheel, Insert a wida bladed screwdriver In the ring gear teeth or alternatively use a piece of angle iron against one of the retaining bolts temporarily Inserted in the cylinder block (see illustration). 3 Turn the crankshaft half a turn and unscrew the remaining bolts, then withdraw the electromagnetic clutch.
Inspection 4 Turn the driven element by means of tha slip rings, and check that the bearing is not noisy or rough. 5 Inspect the slip rings for burning or other damage. Clean them if necessary using fid and a clean rag. 6 Check the resistance of the clutch windings, using an ohmmetor connected across the slip rings (see Illustration). The resistance at 20*0 should be 2 to 4 ohms. 7 Check the Insulation of the windings, using an ohmmeter connected between either sip ring and the body of the clutch (see illustration). Resistance should be Infinity. 8 If the clutch fails any of the foregoing checks, renew it. Apart from the brush gear, Individual spares are not available.
Refitting 9 Refitting is a reversal of removal but tighten all bolts to the specified torque.
windings
Page 190 of 225

Suspension and steering 10*2
Torque wrench settings (continued) Nm ibt ft Rasr suspension Damper lower securing bolt 95 70 Damper upper securing bolt 60 44 Handbrake cable support bracket-to-trailing arm screws 15 11 Hub nut 280 207 Trailing arm securing bolt 150 111 Steering Ignition switch/steering column lock securing bolts 4 3 Steering column mounting bolts 55 41 Steering gear mounting bolts 70 52 Steering wheel nut' 50 37 Subframe-to-body bolts 110 81 Track-rod end to hub carrier 40 30 Unlversaijointclampbolts 20 15 Roadwheels Roadwheel bolts 85 63 * Use a new nut
1 General information
Front suspension The front suspension is independent, comprising transverse lower wishbones, coil spring-over-damper strut units and an anti-roll bar. The hub carriors are bolted to the base of the stmt units and are linked to the lower arms by means ot balliotnts. The entire front suspension assembly is mounted on a subframe, which is In turn botted to the vehicle body.
Rear suspension The rear suspension incorporates a torsion beam axle, trailing arms, coil springs and separate telescopic dampers. In addition, a rear anil-roll bar is fitted to certain models. The components form a discrete sub-assembly which can be unboiled from the underside of the vehicle separately or as a complete unit.
Steering The two-piece steering shaft runs in a tubular column assembly, which is bolted to a bracket mounted on the vehicles bulkhead. The shaft Is articulated at its lower end by means of a universal Joint, which is clamped to the steering shaft and the steering gear pinion by moans of clamp bolts. The steering gear is mounted on the engine compartment bulkhead, and is connected to the steering arms projecting rearwards from Ihe hub carriers. The track-rods are fitted with balljoints at their inner and outer ends, to allow for suspension movement, and are threaded to facilitate ad|ustment. Hydrauiically-assisted power steering ts fittod to some models. The hydraulic system is powered by a belt-driven servo pump, which is driven from the crankshaft pulley.
Certain models are fitted with an airbag system. Sensors built into the vehicle body are triggered in the event of a front end collision and prompt an Electronic Control Unll (ECU) to activate the airbag, mounted In the centre of the steering wheel and the facia. This reduces the risk of the front seat occupants striking the steering wheel, windscreen or facia during an accident.
A
Warning: For safety reasons, owners are strongty advised to entrust to an authorised Flat dealer any work which involves disturbing the airbag system components. The airbag inflation devices contain explosive material and legislation exists to control their handling and storage, in addition, specialised test equipment Is needed to check that the airbag system Is fully operational following reassembly.
2 Front hub bearings -renewal *
Note: A balljoint separator tool, and a press or suitable alternative tools (see text) will be required for this operation. The bearing will be destroyed during the removal procedure.
Removal 1 Chock the rear wheels, apply the handbrake, then jack up the front of the vehicle and support on axle stands (see Jacking and vehicle support). Remove the appropriate roadwheel. 2 Remove the brake disc and caliper, with reference to Chapter 9. Note that the caliper body can remain bolted to its bracket: there is no need lo disconnect the brake fluid hose from the caliper. 3 With reference to Chapter 8. slacken and remove the driveshaft hub nut. 4 On models with ABS, unbolt the ABS wheel sensor, and remove the screw securing the
ABS sensor wiring to the hub carrier. Suspend the sensor away from the working ares, to avoid the possibility of damage. 5 With reference to Section 17, separate
th»
track-rod end from the hub carrier, using
a
suitable balljoint splitter. 6 Remove the two nuts from tho botts securing Ihe hub carrier to the base of th» suspension strut (refer to Section
3).
Withdrew the bolts and separate the top of hub earrtt from the strut. 7 Disconnect the outboard end of Ito driveshaft from the hub, as described durirg the driveshaft removal and refitting procedm in Chapter 8. Note: There is no naod fo disconnect the Inboard end of the
drivestett
from the transmission. Caution: Do not allow the end of tin driveshaft to hang down under its
own
weight, as this places strain on the
CV
joints; support the end of the shaft uskg wire or string. 8 Slacken and remove the nut and clamp bolt, then push the lower arm down anc separate the balljoint from the base of the tab carrier (see illustrations). 9 At this stage, it is recommended that
the bub
carrier be taken to a engineering workshop,
as
the hub and bearing should ideally be removed from the hub carrier using a hydraulic press
2.8a ... Slacken and remove the nut...
Page 195 of 225

Suspension and steering
10*195
5 Front suspension >,•> tower arm balljoint -renewal ^
The balljoint is integral with the suspension ower arm (see Illustration). If the balljoint is worn or damaged, the complete lower arm oust be renewed as described In Section 4.
6 Front suspension ^ anti-roll bar -
removal and refitting s^
Removal 1 Chock the rear wheels, apply the handbrake, then jack up the front of the vehicle and support securely on axle stands •we Jacking and vehicle support). If required, wove the relevant roadwheels. 2 Refer to the Chapter 4D and unbolt the hnt section of the exhaust pipe. 3 Unscrew the bolts securing the anti-roll bar mountings to the suspension lower arms on ether side of the vehicle. Similarly, unscrew
ine
bolts securing the anti-roll bar mountings lo the suspension sub-frame (refer to the Derations in Section 4). 4 lower the anti-roll bar away from the underside of the vehicle. 5 Inspect the rubber bushes for cracks or ietertoratlon, If renewal Is necessary, slide the dd bushes from the bar, and fit the now items, using soapy water as a lubricant. Do rot apply grease or oil as this will attack the •ifiber. 9 Check the anti-roll bar for signs of damage, war or serious corrosion. Refitting 7 Refitting Is a reversal of removal, bearing In
mnd
the following points: sj
D'rw
up the holes af the ends of the anti-roll bar with those on the suspension iov/erarm. til
Tighten
all fixings to the specified torque, but do not do this until the vehicle is resting on its roadwheels, and the suspension has been settled, or damage to the bushes may result.
7.5 Slacken and remove the rear hub nut
5.1 Front suspension lower arm balljoint
7 Rear hub bearings -renewal
Note: 77ie bearing will be destroyed during the removal operation, and a new rear hub/ bearing assembly must be used on refitting -the old hub cannot be re-used. A new rear hub nut must be used on refitting. 1 The rear hub bearings are integral with the hubs themselves, and cannot be renewed separately, tf the bearings require renewal, the complete hub assembly must be renewed as follows. 2 Chock the front wheels, then jack up the rear of the vehicle and support securely on axle slands (see Jacking and vehicle support). Remove the appropriate rear roadwheel. 3 Remove the brake drum as described In Chapter 9. Do not depress the brake pedal whilst the brake drum is removed. 4 Prise the dust cap from the hub. using a mallet and punch. 5 Slacken and remove the hub nut and recover the washer/spacers (see illustration). Caution: The nut Is tightened to a very high torque. Use a long extension bar to remove the nut and ensure that you have access to torque wrench capable of tightening the new nut to the speclfiod torque setting, before removing the existing nut 6 Withdraw Ihe hub and bearing assembly from the stub axle, and recover the inner washer. Discard the hub nut - a new one must be used on refitting.
1
8.3 Slacken and withdraw the damper lower retaining bolt (arrowed)
7 Thoroughly clean tho stub axle, then slide the inner washer and new hub assembly into position. 8 Fit the outer washer, then thread a new hub nut onto the end of the stub axle by hand - do not fully tighten the nut at this stage. 9 Refit the brake drum (Chapter 9). 10 Tighten the hub nut to the specified torque, then check that the hub spins smoothly and freely. Carefully tap the dust cap into position over the nut. 11 Refit the roadwheel, then lower the vehicle to the ground and tighten the road-wheel bolts to the specified torque.
8 Rear suspension components -removal, overhaul and refitting ^
1 Chock the front wheels, then jack up the rear of the vehicle and support on axle stands (see Jacking and vehicle support). Remove the relevant rear roadwheel.
Damper
Removal 2 Using a trolley jack positioned under the trailing arm, raise the trailing arm to take the strain from the damper. 3 Slacken and withdraw the damper lower retaining boll (see Illustration). 4 Lower the jack and allow the damper to separate from the trailing arm. Take care to avoid displacing the coil spring. 5 Slacken and withdraw the damper upper retaining bolt (see illustration). 6 Lower the damper away from the suspension subframe. Refitting 7 Refitting is a reversal of removal. Tighten the damper upper and lower retaining bolts to the specified torque, but delay this operation until the full weight vehicle is resting on the road-wheels • this prevents the damper bushes from being strained.
Coil spring
Removal 8 With reference to the previous sub-Section.
8.5 Slacken and withdraw the damper upper retaining bolt (arrowed)
Page 196 of 225

Suspension and steering 10*8
9.1 Prise the horn centre pad from the steering wheel hub unbolt the lower end of the damper from the trailing arm. 9 Lower the trailing arm gradually using a trolley jack, until the coil spring Is released from its lower seat on the trailing arm and its upper seat on the subframe. Make a note of the orientation of the coll spring, to aid correct refitting later. Refitting 10 Refitting is a reversal of removal, lighten the damper lower retaining bolt to the specified torque. Trailing arm Note: The rear stub axles are integral with the trailing arm assemblies and cannot be renewed separately. Removal 11 With reference to Chapter 9. carry out the following: a) Remove the brake drum, shoes and adjuster assembly. b) Unbolt the brake hose union from the
rear
of the wheel cylinder. c) Unbolt the brake pipe mounting bracket from the trailing arm. 12 Refer to Section 7 and remove The rear hub and beanng assembly. 13 With reference to the relevant sub-Section, unbolt the lower end of Ihe damper from the trailing arm. 14 Raise the trailing arm using a trolley jack so that the coll spring Is compressed, then slacken and withdraw the trailing arm front mounting bolL 15 With reference to the previous sub-Section, gradually lower the trailing arm using a trolley lack and remove the coll spring. 16 Allow Ihe trailing arm to hang down, then pull the leading edge of the arm down from its mounting bracket. Refitting 17 Refitting Is a reversal of removal. Tighten all suspension fixings to the specified torque settings, but delay this operation until the full weight vehicle is resting on the roadwheeis -this prevents the damper and trailing arm bushes from being strained. 18 On completion, bleed the brake hydraulic system and adjust the operation of the handbrake, with reference to Chapter 9.
9.2 Unplug the wiring from the centre pad at the connector(s)
9 Steering wheel - % removal and refitting ^
Note: This procedure does not apply to vehicles fitted with an airbag A Warning: For safety reasons, owners are strongly advisod to entrust to an authorised Fiat dealer any work which involves disturbing the airbeg system components. The airbag inflation devices contain explosive material and legislation exists to control their handling and storage. In addition, specialised test equipment Is needed to check thet the alrbag system Is fully operational following reassembly.
Removal 1 Ensure that the ignition is switched off, then prise the horn centre pad from the steering wheel hub. Use the blade of a screwdriver, padded with PVC tape to protect the steering wheel (see illustration) 2 Unplug the horn and (where applicable) radio/cassette control switch wiring from the centre pad at the connectors) (see illustration) 3 Turn the steering wheel to its centre position, so that the roadwheeis are pointing straight ahead. 4 Make alignment marks between the steering wheel and the end of the steering column shaft, to aid correct refitting later, 5 Relieve the staking and then slacken and remove tne steenng wheel securing nut (see
9.5 Slacken and remove the steering wheel securing nut Illustration). Discard the nut as a new item must used on refitting. 6 Lift the steering wheel off the column splines. If it is tight, tap il near the centre, usrg the palm of your hand, or twist it from
side to
side, whilst pulling upwards to release il ton the shaft splines. If the wheel is particular tight, a suitable puller should be used.
Refitting 7 Before commencing refitting, lightly eca. Ihe surfaces of the direction indicator cancelling mechanism with grease. 8 Refitting is a reversal of ren>oval.
bearing a
mind the following points: a) Use a new steering wheel
securing not
and tighten it to the specified
torque.
Ensure that its outer collar
Is adequate^
staked to the column shaft
using a
hammer and punch (see Illustrations). b) Ensure that the direction Indicator
swiith
is in the central (cancelled/off)
position,
otherv/ise the sivitch may be damaged X the wheel Is refitted. c) Align the marks made on the
wheel and
Ihe steering column shaft during removeI 9 Note that if necessary, the position of tf* steering wheel on the column shaft cant* | altered in order to centralise the wheel (enstn that the front roadwheeis aro pointing
In the
straight-ahead position), by moving the vMti the required number of splines on the
sfcafc
Fine adjustment can be carried out by adjusting the length of both track-rwa simultaneously, but this operation is best entrusted to a Rat dealer or tyre specialist
9.8a Fit a new steering wheet securing nut... 9.3b ... and stake it to the steering column shaft using o hammer and punch
Page 199 of 225

Suspension and steering 10*11
13.11b ... and left-hand steering gear-to-subframe bolts
hooked onto the engine lifting eyelet on the cylinder head. Working underneath the vehicle, unbolt and remove the transmission-lo-subframe rear mounting bracket. 13 Position a trolley jack under the right hand skle of the subframe crossmember. Raise the jack to take the weight of the crossmember
and
the attached components. 14 With reference to Section 4, slacken and remove the two bolts that secure the suspension lower arm rear bush to the subframe. Slacken and withdraw the subframe-to-bodywork bolt, located adjacent to the rear of the suspension lower arm. Throad two flange head bolts of the same thread size, but approximately 25 mm longer into the vacated holes, then carefully lower
the
trolley jack and allow ihe subframe to rest on the heads of the temporary bolts (see (lustration), 15 Repeat the operations in paragraphs 13 end 14 at the left-hand side of the vehicle. On completion, the subframe should be resting at
&
height approximately 25 mm lower than normal. 16 The additional clearance will now permit the steering gear pinion to be lowered away from the bulkhead. When the end of the pinion has cleared Ihe aperture, manoeuvre the entire steering gear assembly through the *tiae?arch.
Refitting 17 Refitting is a reversal of removal, noting
the
following points: s) Remote the temporary bolts and refit the original length fixings.
13.14 Slacken and remove the subframe-to-bodywork bolts (arrowed)
b) Tighten all fixings to the specified torque settings. c) Refill the hydraulic system with the specified grade and quantity of power steering fluid (see Lubricants and fluids In Weekly checks), then thoroughly bleed the system as described in Section 15. d) On completion, have the front wheel alignment checked at the earliest oppor-tunity by a Flat dealer or a tyre specialist.
14 Steering gear rubber gaiters - renewal <
Note: New gaiter retaining clips should be used on refitting. 1 Remove the relevant track-rod end as described in Section 17. 2 If not already done, unscresv the track-rod end locknut from Ihe end of the track-rod. 3 Mark the correct fitted position of the gaiter on the track-rod, then release the gaiter securing clips. Slide the gailer from the steering gear, and off the end of the track-rod. 4 Thoroughly clean tho track-rod and the steering gear housing, usrng fine abrasive paper to polish off any corrosion, burrs or sharp edges, which might damage the new gaiter sealing lips on installation. Scrape off all the grease from the old gaiter, and apply it to the track-rod inner balljoint. (This assumes that grease has not been lost or contaminated as a result of damage to the old gaiter. Use fresh crease if In doubt.) 5 Carefully slide the new gaiter onto the track-rod. and locate it on the steering gear housing. Align the outer edge of the gaiter with the mark made on the track-rod prior to removal, then secure it in position with new retaining clips. 6 Screw the track-rod end locknut onto the end of the track-rod. 7 Refit the track-rod end as described in Section 17.
15 Power steering hydraulic system • bleeding ^
General 1 The following symptoms indicate that there is air present In the power steering hydraulic system: a) Generation of air bubbles in fluid reservoir. b) Clicking noises from power steering pump. c) Excessive buzzing or groaning from power steering pump. 2 Note that when the vehicle Is stationary, or while moving the steering wheel slowly, a hissing noise may be produced In the steering gear or the fluid pump. This noise is inherent in the system, and does not indicate any cause for concern.
Bleeding 3 Chock the rear wheels, apply the handbrake, then jack up the front of the vehicle and support securely on axle stands (see Jacking and vehicle support). 4 Check the fluid level in the power steering fluid reservoir (bear in mind that the vehicle will be tilted, so the level cannot be read accurately), and if necessary top-up to just above the relevant level mark. 5 Have an assistant tum the steering quickly from lock to lock, and observe tho fluid level, if the fluid level drops, add more fluid, and repeat the operation until the fluid level no longer drops. Failure to achieve this within a reasonable period may indicate a leak in the system. 6 Stan the engine and repeat the procedure described In the previous paragraph. 7 Once the fluid level has stabilised, and all air has been bled from the system, lower the vehicle to the ground.
16 Power steering pump - Sk removal and refitting ^
Removal 1 Drain as much fluid as possible from the power steering reservoir, using a pipette or an old poultry baster. 2 Remove the clip and disconnect the rubber fluid supply hose from the port on the top of the power steering pump. Be prepared for an amount of fluid loss • position a container underneath the port and pad the surrounding area with absorbent rags. 3 Slacken the union and disconnect the fluid delivery hose from the side of the power steering pump. Again, be prepared for an amount of fluid loss. 4 Unscrew tho clamp bolt and through-bolt at either end of the drivebelt guard, then detach Ihe guard from the power steering pump (see illustrations). 5 Partially unscresv the two power steering pump mounting bolts then rotate the pump towards the engine slightly, to release the tension from the belt. Carefully ease the drivebelt from the pump pulley.
16.4a Unscrew the clamp bolt...
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Suspension and steering 10*13
the skill required to use It properly, the checking and adjustment of these settings Is best left to a Fiat dealer or similar expert. Most tyre-fitting shops now possess sophisticated checking equipment. 3 For accurate checking, the vehicle must be at the kerb weight specified in Dimensions and weights. 4 Before starting work, check first that the tyre sizes and types are as specified (see Tyre pressures in Weekly checks), then check tyre pressures and tread wear. Also check roadwheel run-out, the condition of the hub bearings, the steering wheel free play and the condition of the front suspension components (Steering and suspension check in Chapter 1A or
1B).
Correct any faults found. 6 Park the vehicle on level ground, with the front roadwheeis in the straight-ahead position. Rock the rear and front ends to settle the suspension. Release the handbrake and roll the vehicle backwards approximately 1 metre, then forwards again, to relieve any stresses in the steering and suspension components. 6 Two methods are available to the home mechanic for checking the front wheel toe setting. One method is to use a gauge to measure the distance between the front and rear inside edges of the roadwheeis. The other method is to use a scuff plate, in which each front wheel is rolled across a movable plate which records any deviation, or scuff, of the tyre from the straight-ahead position as It moves across the plate. Such gauges are available in relatively-inexpensive form from accessory outlets. It Is up to the owner to decide whether the expense is justified, In view of the small amount of use such equipment would normally receive. 7 Prepare the vehicle 8S described in paragraphs 3 to 5 above.
8 If the measurement procedure is being used, carefully measure the distance between the front edges of the roadwheel rims and the rear edges of the rims. Subtract the front measurement from the rear measurement, and check that the result is within the specified range. If not, adjust the toe setting as described in paragraph 10. 9 If scuff plates are to be used, roll the vehicle backwards, check that the roadwheeis are in the straight-ahead position, then roll it across the scuff plates so that each front roadwheel passes squarely over the centre of its respective plate. Note the angle recorded by the scuff plates. To ensure accuracy, repeat the check three times, and take the average of the three readings, if the roadwheeis are running parallel, there will of course be no angle recorded; If a deviation value Is shown on the scuff plates, compare the reading obtained for each wheel with that supplied by the scuff plate manufacturers. If the value recorded is outside Ihe specified tolerance, the toe setting is incorrect, and must be adjusted as follows. Adjustment 10 Apply the handbrake, then jack up the front of the vehicle and support it securely on axle stands (see Jacking and vehicle support). Turn the steering wheel onto full-left lock, and record the number of exposed threads on the right-hand track-rod. Now turn the steering onto full-right lock, and record the number of threads on the left-hand side. If there are the same number of threads visible on both sides, then subsequent adjustment should be made equally on both sides. If there are more threads visible on one side than the other, it will be necessary to compensate for this during adjustment Note: It is important to ensure that, after adjustment, the same number of threads are visible on the end of each track-rod.
11 First clean the track-rod threads; If they are corroded, apply penetrating fluid before starting adjustment. Release the steering gear rubber gaiter outboard clips, then peel back the gaiters and apply a smear of grease, so that both gaiters are free and will not be twisted or strained as their respective track-rods are rotated. 12 Use a straight-edge and a scriber or similar to mark the relationship of each track-rod to the track-rod end. Working on each track-rod end in tum, unscrew its locking nut. 13 Alter the length of the track-rods, bearing In mind the note in paragraph 10, by screwing them into or out of the track-rod ends. Rotate the track-rod using an open-ended spanner fitted to the flats provided. If necessary, counterhold the track-rod end using a second spanner. Shortening the track-rods (screwing them Into their track-rod ends) will reduce toe-in and increase toe-out. 14 When the setting Is correct, hold the track-rods and securely tighten the locking nuts. Check that the balljoints are seated correctly In their sockets, and count the exposed threads on the ends of the track-rods. If the number of threads exposed is not the same on both sides, then the adjustment has not been made equally, and problems will be encountered with tyre scrubbing in turns; also, the steering wheel spokes will no longer be horizontal when the wheels are in the straight-ahead position. 15 When the track-rod lengths are the same, lower the vehicle to the ground and re-check the toe setting; readjust if necessary. When the setting is correct, tighten the locking nuts. Ensure that the steering gear rubber gaiters are seated correctly and are not twisted or strained, then secure them In position with new retaining clips.
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