pressure FIAT PUNTO 1996 176 / 1.G Manual PDF

Braking system 9®11
Bleeding • using a one-way valve kit 21 As their name implies, these kits consist ol a length of tubing with a one-way valve Fitted, to prevent expelled air and fluid being drawn back into the system; some kits include a translucent container, which can be positioned so that the air bubbles can be more easily seen flowing from the end of the tube. 22 The kit is connected to the bleed screw, which is then opened. The user returns to the driver's seat, depresses the brake pedal with a smooth, steady stroke, and stowty releases it; this is repeated until the expelled fluid is clear of air bubbles. 23 Note that these kits simplify work so much that It is easy lo forget the master cylinder reservoir fluid level; ensure that this Is maintained at least above the MIN level line at all times.
Bleeding -using a pressure-bleeding kit 24 These kits are usually operated by the reservoir of pressurised air contained in the spare tyre. However, note that it will probably be necessary to reduce the pressure lo a lower level than normal; refer to the instructions supplied with the kit. 2$ By connecting a pressurised, fluid-filled container to the master cylinder reservoir, bleeding can be carried out simply by opening each screw In turn (in the specified sequence), and allowing the fluid to flow out until no more air bubbles can be seen in the expelled fluid. 28 This method has the advantage that the large reservoir of fluid provides an additional safeguard against air being drawn into the system during bleeding. 27 Pressure-bleeding is particularly effective when bleeding 'difficult' systems, or when bleeding the complete system at the time of routine fluid renewal.
All methods 28 When bleeding is complete, and firm pedal feel is restored, wash off any split fluid, lighten the bleed screws securely, and refit their dust caps (where applicable). 29 Check the hydraulic fluid level in the master cylinder reservoir, and top-up if necessary. 30 Discard any hydraulic fluid thai has been Wed from the system; it will not be fit for re-use. 91 Check the feel of the brake pedal. If it feels at all spongy, air must still be present in Vie system, and further bleeding is required. Failure to bleed satisfactorily after a reasonable repetition of the bleeding procedure may be due to worn master cylinder seals.
12 Master cylinder- % removal
and
refitting SK

A


Warning: 8efore starting work, refer to the warning at the beginning of Section 11 concerning the dangers of hydraulic fluid.
Removal 1 Remove the master cylinder fluid reservoir cap, and syphon the hydraulic fluid from the reservoir. Note: Do not syphon the fluid by mouth, as It Is poisonous; use a syringe or an old poultry baster. Alternatively, open any convenient bleed screw In the system, and gently pump the brake pedal to expel (he fluid through a tube connected to the screw (see Section 11). Disconnect the wiring connector from the brake fiuld level sender unit. 2 Carefully prise the fiuld reservoir from the seals and release it from the top of the master cylinder. 3 Wipe clean Ihe area around the brake pipe unions on the side of the master cylinder, and place absorbent rags beneath the pipe unions to catch any surplus fluid. Make a note of the correct fitted positions of the unions, then unscrew the union nuts and carefully withdraw the pipes. Plug or tape over the pipe ends and master cylinder orifices, to minimise the loss of brake fluid, and to prevent the entry of dirt into the system. Wash off any spilt fluid immediately with cold wafer.
A 22.45 to 22.65 mm
Cut the finger tips from an old rubber glove end secure them over the open ends of the brake pipes with elastic bands • this wifi heip to minimise fluid lots and prevent the Ingress of contaminants.
4 Slacken and remove the nuts securing the master cylinder to the vacuum servo unit, then withdraw the unit from the engine compartment. 5 Where applicable, recover the seals from the rear of the master cylinder, and discard them; new items must be used on refitting. 8 With the master cylinder removed, check that the distance between the end of the vacuum servo unit pushrod and the master cylinder mating surface is as shown in the diagram. If necessary, the distance may be adjusted by turning the nut at the end of the servo unit pushrod (see illustration).
Refitting 7 Fit new rubber seals and then press the fluid reservoir into the ports at the top of the master cylinder 8 Remove all traces of dirt from the master cylinder and servo unit mating surfaces, and where applicable, fit a new seal between the master cylinder body and the servo. 9 Fit the master cylinder to the servo unit, ensuring that the servo unit pushrod enters the master cylinder bore centrally. Refit the
B Adjustment nut

10*1
Chapter 10
Suspension and steering
Contents
Front hub bearings - renewal 2 Front suspension anti-roll bar • removal and refitting 6 Front suspension lower arm - removal and refitting 4 Front suspension lower arm balljolnt - renewal 5 From suspension strut - removal, overhaul and refitting 3 General information 1 Ignition switch/steering column lock - removal and refitting 10 Manual steering gear assembly - removal, overhaul and refitting ... 12 Power steering fluid level check See Weekly checks Power steering gear assembly - removal and refitting 13 Power steering hydraulic system - bleeding 15
Degrees of difficulty
Power steering pump • removal and refitting 16 Rear hub bearings - renewal 7 Rear suspension components- removal, overhaul and refitting 8 Steering and suspension check See Chapter 1A or 1B Steering column - removal, overhaul and refitting 11 Steering gear rubber gaiters - renewal 14 Steering wheel - removal and refitting 9 Track-rod end - removal and refitting 17 Wheel alignment and steering angles • general information 18 Wheel and tyre maintenance and tyre pressure checks See Weekly checks

Easy, suitable for nowoe with little
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Fakty easy,
suitable for beginner
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some experience
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FaMy difficult,
% suitable for competent ^
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Difficult,
suitable for & experienced DIY « mechsmc ^

Very difficult,
^ suitable for expert
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Specifications
Front suspension Type
Rear suspension Type
Steering Type Turns lock-to-lock: Manual Power assisted Toe setting (front)
Roadwheeis and tyres See Weekly checks
Torque wrench settings Front suspension Anti-roll bar bush bracket bolts Driveshaft nut:' All models except turbo diesel (M22 plain) Turbo diesel (M24 with staking and captive washer) Lower arm balljoint to hub carrier Lower arm front bush securing bolt Lower arm rear bush securing bolt Suspension strut damper nut Suspension strut to hub carrier Suspension strut to inner wing
Independent, incorporating transverse lower wishbones and coil spring-over-teiescopic damper strut units. Anti-roll bar fitted to all models.
Independent, incorporating trailing arms with telescopic dampers and coil springs.
Rack-and-pinlon, manual or power assisted, depending on model
4.4 approx. 2.9 approx. 0° (parallel) ± 1a
Nm ibfft
30 22
240 177 280 207 30 22 95 70 70 52 60 44 70 52 50 37

Suspension and steering 10*3
2.10 Using a slide hammer to extract the hub 2.11 Wheel bearing components / Hub carrier 2 Wheel bearing 3 Circlip
Owners wishing to attempt the work them-
selves
should proceed as follows. 10 Mount tho hub carrier firmly In a bench vice. Attach a slide hammer to the hub flange and extract the hub. together with the inner bearing race, If it has remained attached to the hub. Unbolt and remove the heat shield
(see
Illustration). 11 Mount the hub carrier horizontally in the rice, then remove tho bearing retaining circlip. Using a suitable length of tubing as a drift, drive Ihe bearing outer race from the carrier (see Illustration). Note that a flange on the outboard side of the carrier means that the bearing can only be driven out in one direction. 12 Support the inner bearing race, if it has remained attached to the hub, then press or drive the hub from the race. Alternatively, pull trie bearing race from the hub using a suitable Iw or three-legged puller. 13 Before Installing the new bearing, thoroughly clean the bearing location in the tub carrier. U Fit the new bearing from the Inboard side the hub: press or drive the bearing into position, applying pressure only to the bearing oiler race. Oo not lubricate the mating surface
ol the
bearing In an attempt to ease installation. 15 Fit the bearing retaining circlip to its 700ve in the hub carrier, then refit the heat
shield and tighten the retaining screw securely. 16 Support the outer face of the hub carrier across the jaws of a bench vice. 17 Carefully press or draw the hub into the bearing, noting that the bearing inner race must be supported during Ihis operation, to prevent It from being separated from the outer race. This can be achieved using a suitable socket, threaded rod, washers and a length of bar (see Illustration). 18 On completion, check that the hub rotates freely in the hub carrier without resistance or roughness.
2.17 Typical method of drawing the hub into the wheel bearing using improvised tools
Refitting 19 Reconnect the outboard end of the drive-shaft to the hub as described In Chapter 8. Ensure that the driveshaft nut is tightened to the correct torque and adequately staked. Ideally, for safety reasons due to the very high torque of the driveshaft nut, carry out final tightening and staking of the nut after refitting the roadwheel and lowering the car to the ground. 20 Reconnect the hub carrier to the lower arm balljoint, then fit a new clamp bolt nut. Tighten tho nut to the specified torque. 21 Engage the hub carrier with the suspension strut, then refit the securing bolts and nuts, tightening them to the specified torque. 22 Reconnect the steering track-rod balljoint to the hub carrier steering arm. Use a new nut and tighten it to the specified torque. 23 Refer to Chapter 9 and refit the brake disc and caliper. 24 Where applicable, fit the ABS wheel sensor into its mounting hole and tighten the securing screw. 25 Refit the roadwheel, and tower the vehicle to the ground. 26 Have the front wheel alignment checked by a Fiat dealer or a tyre specialist at the earliest opportunity.

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.
10