2B*10 DOHC (16-valve) petrol engine in-car repair procedures
9.10 Extract the exhaust camshaft oil seal...
Inspection 12 Examine the camshaft bearing surfaces and cam lobes for signs of wear ridges and scoring. Renew ihe camshaft If any of these conditions are apparent. Examine the condition of the bearing surfaces, both on the camshaft journals and in the cylinder head extension. If the head extension beanng surfaces are worn excessively, the extension will need to be renewed. If suitable measuring equipment Is available, camshaft bearing journal wear can be checked by direct measurement. 13 Examine the cam follower bearing surfaces which contact the camshaft lobes for wear ridges and scoring. Renew any follower on which these conditions are apparent. If a follower bearing surface is badty scored, also examine the corresponding lobe on the camshaft for wear, as it is likely that both will be worn. Renew worn components as necessary.
9.11 ... then remove the exhaust camshaft from the cylinder head extension
Refitting 14 Liberally lubricate the camshaft journals and cylinder head extension bearings, then locate both camshafts in position Note that the exhaust camshaft is nearest to the front facing side of the engine. 15 With the camshafts In position, rotate them as necessary until the camshaft locking tools can be re-inserted (see illustration). 16 Lubricate the Hps of a new exhaust camshaft oil seal with clean engine oil, and drive It into position until it seats on its locating shoulder (see Illustration). Use a suitable tubular drifl, such as a socket, which bears only on the hard outer edge of the seaJ. Take care not to damage the seal lips during fitting. Noto that the seal lips should face inwards. 17 Refit the Inlet camshaft drive gear and retaining boll then tighten the bolt to the specified torque (see illustration).
9.16 Fit a new exhaust camshaft oil seal M7 Tighten the Inlet camshaft drive gear retaining bolt to the specified torque
9.15 Refit the camshaft locking tools
18 Refit the exhaust camshaft drive gear to the exhaust camshaft. As the gear is being fitted, It will be necessary to align the anti» backlash inner gear teeth using a screwdriver to enable the teeih of both Ihe gears to mes-i (see Illustration). 19 At this stage it is advisable lo check tie camshaft endfloat using a dial gauge mounted on the cylinder head extension, with its probe in contact with Ihe camshaft being checked Move the camshaft one way. zero the gauge, then move the camshaft as far as it will go ihe other way. Record the reading on the dial gauge and compare the figure with that given in the Specifications. Repeat on the other camshaft. If either of the readings exceeds the tolerance given, a new cylinder head extension will be required. 20 Locate a new gasket on the cylinder head extension end cover, then wrap round the protruding tangs on Ihe gasket to retain it in position (see Illustrations). 21 Locate the end cover on the cylinder heed extension and secure with the retaining nuts securely tightened. 22 Locate a new O-ring on the inlet camshaft cover plate, then apply RTV gasket sealant lo the cover plate contact face (see Illustrations), Fit tho cover plate and secure with the nut and bolt. 23 Refit the camshaft sprocket and secure with the retaining bolt tightened finger tight only at this stage. 24 Liberally lubricate the cam followers and piece them in position in their respective cylinder head extension bores (see illustration),
9.18 Refit the exhaust camshaft drive gear white aligning the anti-backlash Inner gear teeth 9.20a Locate a new gasket on the cylinder head extension end cover... 9.20b ... then wrap round the protruding tangs to retain the gaskel
2D*10 Engine removal and overhaul procedures
8.4 Using a dial gauge to check the crankshaft endfloat 2 Remove the pistons and connecting rods, as described in Section 7. However, If no work fs to be done on the pistons and connecting rods there is no need to remove the cylinder head, or to push the pistons out of the cylinder bores. The pistons should just be pushed far enough up the bores that they are positioned clear of the crankshaft Journals. 3 Unbolt the crankshaft rear oil seal housing from the cylinder block and recover the gasket where fitted. 4 Before removing the crankshaft, check the endfloat using a dial gauge. Push the crankshaft fully one way, and then zero Ihe gauge. Push the crankshaft fully the other way, and check tho endfloat (see Illustration). The result can be compared with the specified amount, and will give an indication as to whether new thrustwashers are required. 6 If a dial gauge is not available, feeler blades can be used. First push the crankshaft fully towards the flywheel end of the engine, then use feeler blades to measure the gap - on petrol engines measure between the centre main bearing thrust washer and the crankshaft web. and on diesel engines measure between the rear main bearing and tha crankshaft web. 6 Note the markings on the main bearing caps which vary according to type. On 8-valve petrol engines there is one line on Ihe cap nearest the timing belt end, two on the second cap, C on the centre cap, then three and four lines on the remaining caps (soo illustration). On 16-valve petrol engines, the caps are marked one to five with a series of lines (one line for the cap nearest the timing
8.6 Main bearing markings (petrol engine)
belt end, two for tho next cap and so on). On diesel engines the caps are marked one to live In the same way but with notches instead ol lines. Note also that on some diesel engines the cap nearest the timing belt end Is not marked and the notches therefore start with No 2 cap. 7 Loosen and remove the main bearing cop retaining bolts, and lift off each bearing cap. Recover the lower bearing shells, and tape them to their respective caps for safe-keeping. On some diesel engines note that the centre main bearing cap botts are longer than the other bolls. 8 Lift the crankshaft Irom the crankcase and remove the upper bearing shells from the crankcase. If the shells are 1o be used again, keep them identified for position. Also remove the thrustwashers from their position either side of the centre main bearing (petrol engines) or rear main bearing (diesel engines) (see illustrations)
Inspection 9 Wash the crankshaft in a suitable solvent and allow It to dry. Flush the oil holes thoroughly, to ensure that ihey are not blocked - use a pipe cleaner or a needle brush il necessary. Remove any sharp edges from the edge of the holes which may damage the new bearings when they are installed. 10 Inspect the main searing and crankpin journals carefully; if uneven wear, cracking, scoring or pitting are evident then the crankshaft should be reground by an engineering workshop, and refitted to the engine with underslze bearings.
11 Use a micrometer to measure the diameter of each main bearing journal. Taking a number of measurements on the surface of each journal will reveal if it Is worn unevenly. Differences in diameter measured at 90" intervals Indicate that the journal is out of round. Differences In diameter measured aiong the length of the journal, indicate that the journal is tapered. Again. If wear is detected, the crankshaft can be reground by an engineering workshop and refitted with undersize bearings. 12 Check the oil seal journals at either end of the crankshaft. If they appear excessively scored or damaged, they may cause the new seals to leak when the engine is reassembled. It may be possible to repair the |ournal; seek the advice of an engmeenng workshop. 13 Measure the crankshaft runoul by setting up a DTI gauge on the centre main bearing journal and rotating the shaft In V - blocks. The maximum deflection of the gauge will indicate Ihe runout. Take precautions to protect the bearing journals and oil seal mating surfaces from damage during this procedure. A maximum runout figure Is not quoted by the manufacturer, but use the figure of 0.05 mm
a»
a rough guido. If the runoul exceeds this figure, crankshaft renewal should be considered • consult your Flat dealer or an engine rebuilding specialist for advico. 14 Refer to Section 10 for details of main and big-end bearing inspection.
9 Cylinder block/crankcase - % cleaning and inspection Sk
Cleaning 1 Remove all external components, brackets and electrical switches/sensors from the block Including the rear engine plate, injection pump/oil filter bracket and gasket, Intermediate shaft bracket, oH vapour breather casing, and coolant pump. Also unboit and remove the ol return tube from the crankcase (see illustrations). For complete cleaning, the core plugs should Ideally be removed. Drill a small hole in the plugs, then insert a self-tapping screw into the hole. Pull out the plugs by
8.8a Removing the thrustwashers.. ... and upper bearing shells (diesel engine) 8.8o Thrustwashers located on the centre main bearing (petrol engine)
2D*10 Engine removal and overhaul procedures
12.5 Lowering the crankshaft into the crankcase
12.9 Fit tho main bearing caps...
to allow lubricant to circulate. This clearance is impossible to check using feeler blades, however Plastlgauge can be used. This consists of a thin strip of soft plastic that is crushed between the bearing shells and journals when the beanng caps are tightened up. Its width then indicates the size of the clearance gap. 7 Cut off five pieces of Plastlgauge. just shorter than the length of the crankshaft journal. Lay a piece on each journal, in line with its axis (see Illustration). 8 Wipe off the rear surfaces of the new lower half main bearing shells and fit them to the main beanng caps, again ensuring that the locating lugs engage correctly (see illustration). 9 Fit the caps in their correct locations on the bearing saddles, using the manufacturers markings as a guide (see illustration). Ensure lhat Ihey are correctly orientated • the caps should be fitted such that the recesses (or the bearing shell locating lugs are on the same side as those in the bearing saddle. 10 Insert and tighten the bolls until they are
811
correctly torqued (see illustrations). Do not allow the crankshaft to rotate at all whilst ihe Plastlgauge is in place. Progressively unbolt the bearing caps and remove them, taking care not to dislodge the Plastlgauge. 11 The width of the crushed Plastigauge can now be measured, using the scale provided (see illustration). Use the correct scale, as both Imperial and metric are printed. This measurement Indicates the running clearance • compare it with that listed in the Specifications.
21 \ „ 12.7 Lay the Plastigauge on the main bearing journals
t
12.10a ... Insert the bolts...
If tho clearance is outside ihe tolerance, it may be due to dirt or debns trapped under the bearing surface; try cleaning them again and repeat the clearance check. If the results are still unacceptable, re-check Ihe journal diameters and the bearing sizes. Note that if the Plastigauge is thicker at one end. the loumals may be tapered and as such, will require regrinding. 12 When you are satisfied that the clearances are correct, carefully remove the remains of the Plastigauge from the journals and bearings faces. Use a soft, plastic or wooden scraper as anything metallic is likely to damage the surfaces.
Crankshaft • final refitting 13 Lift the crankshaft out of the crankcase. Wipe off the surfaces of the bearings in the crankcase and the bearing caps. Fit the thrust beanngs using grease to hold them in
12.11 Use the special scale card to determine the main bearing running clearance
shell In its cap
12.10b ... and torque-tighten them
position, Ensure they are seated correctly in the machined recesses, with tho oil grooves facing outwards 14 Liberally coat the bearing shells in the crankcase with dean engine oil (see Illustration). 15 Lower the crankshaft into position in the crankcase. 16 Lubricate the lower bearing shells in the main bearing caps with clean engine oil. Make sure that the locating lugs on the shells are still engaged with the corresponding recesses in the caps. 17 Fit the main bearing caps in the correct order and orientation. Insert the bearing cap bolts and hand tighten them only. 18 Working from the centre bearing cap outwards, tighten the retaining bolts to their specified torque. On petrol engines, tighten all the bolts to the first stage, then angle-tighten them to the Stage 2 anglo (see illustration)
12.14 Lubricate the main bearing shells before final assembly
4C»1
Chapter 4 PartC:
Fuel system - diesel models
Contents
Accelerator cable • removal, refitting and adjustment 3 Air cleaner and inlet system • removal and refitting 2
AJr
cleaner filter element - renewal See Chapter IB Fuet filter renewal See Chapter 1B Fuel gauge sender unit • removal and refitting 10 Fuel injection pump • removal and refitting 5 Fuel injectors - testing, removal and refitting 9
Fuel
system • priming and bleeding 4
Fuel
tank - removal and refitting 11 General Information and precautions 1
Idle speed - checking and adjustment See Chapter 1B Injection timing • checking methods 6 injection timing {Bosch fuel Injection pump) • checking and adjustment 7 Injection timing (Lucas fuel Injection pump) - checking and adjustment 8 Inlet manifold - removal and refitting 12 Turbocharger - description and precautions 13 Turbocharger - examination and renovation 15 Turbocharger - removal and refitting 14
Degrees of difficulty
Easy,
suitable for novice
with Ittle
p experience sS^
Fairly easy, suitable (or beginner with some experience
Fairly tfifficuit, suitable
for
competent ^
DIY
mechanic
Difficult, suitable
for ^ experienced DIY jR mechanic ^
Very difficult, ^ sutable for expert
DIY
S or professional ^
Specifications
General System type
Firing order
Injection pump (Bosch VE) Direction of rotation Static timing: Engine position Pump timing measurement Maximum engine speed
Injection pump (Lucas/CAV FT08) Direction of rotation Static timing: Engine position Pump timing measurement Maximum engine speed
injectors Type Opening pressure: Bosch Lucas: New After running in
RPM sensor Sensor-to-flywheel ring gear teeth gap — Winding resistance
Rear-mounted fuel tank, distributor fuel injection pump with integral transfer pump. Indirect Injection, Turbocharger on TDS, TD and TDSX models 1-3-4-2 (No
1
at timing belt end of engine)
Clockwise, viewed from sprocket end
No
1
piston at TDC 0.93 ± 0.05 mm 5200 to 5300 rpm
Clockwise, viewed from sprocket end
No 1 piston at TDC 0° ± 1° TDC (Note: Value shown on pump - see text} 5150150 rpm
Pintle
150 to 158 bar
124 to
131
bar 116lo123 bar
0.25 to 1.3 mm 680* 100 ohms
Fuel system - diesel models
4C*3
7.4 Unscrew the access screw from the 7.5 Dial gauge and adapter (Bosch) rear of the Injection pump (Bosch)
7 Injection timing ^ (Bosch fuel injection pump) -checking and adjustment ^
Caution: Some of the Injection pump uttlngs and access plugs may be sealed ty the manufacturers at the factory, using
paint
or locking wire and lead seals. Do not
disturb
the seals If the vehicle is still within the warranty period, otherwise the warranty will be invalidated. Also do not attempt the timing procedure unless
accurate
Instrumentation Is available. Note: To check the injection pump timing a special
timing
probe and mounting bracket is required. Without access to this piece of
tquipment.
injection pump timing should be intrusted to a Fiat dealer or other suitably
eqwpped
specialist. 1
H
the Injection timing is being checked with ffie pump in position on the engine, rather rian as part ot the pump refitting procedure, disconnect the battery negative terminal (refer to
Disconnecting
the battery in the Reference S«ction of this manual), and remove the air rtel ducting from the front of the engine. 2 Unscrew the union nuts and disconnect the injector pipes from the Injection pump and injectors. Counterhold the unions on the pump, while unscrewing the pipe-to-pump irion
nuts.
Remove the pipes as a set. Cover open unions to keep dirt out, using small plastic bags, or fingers cut from discarded
ibut clean!)
rubber gloves. 3 Referring to Chapter 2C, set the engine at
TDC on
cylinder No 1. 4 Unscrew the access screw, situated In the centre of the four injector pipe unions, from the rear of the Injection pump (see illustration). As the screw Is removed, position a suitable container beneath the
pump
to catch any escaping fuel, Mop up any tpilt fuel with a clean cloth. 5 Screw the adapter into the rear of the pump
and
mount the dial gauge in ihe adapter (see •ustration). If access to the special Fiat *Japter cannot be gained, they can be purchased from most good motor factors. Position the dial gauge so that its plunger is at
Ifce
mid-point of its travel and securely tighten Ite adapter locknut. 6 Slowly rotate the crankshaft first back then towards whilst observing the dial gauge, to ctotermlne when the Injection pump piston is
a',
the bottom of Its travel (BDC), When the pston Is correctly positioned, zero the dial
7 Rotate the crankshaft slowly in the correct direction until the TDC timing marks are tfjned on both the crankshaft, camshaft and rjecbon pump sprockets.
6
The reading obtained on the dial gauge should be equal to the specified pump timing measurement given in the Specifications at ew start of this Chapter, If adjustment is necessary, slacken the fronl and rear pump mounting nuts/bolts and slowly rotate the
pump body until the point is found where the specified reading Is obtained. When the pump is correctly posilioned, tighten both its front and rear mounting nuts and bolts securely. 9 Rotate the crankshaft through one and three quarter rotations in the normal direction of rotation. Find the injection pump piston BDC as described in paragraph 6 and zero the dial gauge. 10 Rotate the crankshaft slowly in the correct direction of rotation until the TDC marks are aligned. Recheck the timing measurement. 11 If adjustment is necessary, slacken the pump mounting nuts and bolts and repeat the operations In paragraphs 8 to 10. 12 When the pump timing Is correctly set, unscrew the adapter and remove the dial gauge. 13 Refit the screw and sealing washer to the pump and tighten it securely. 14 If the procedure is being carried out as part of the pump refitting sequence, proceed as described in Section 5, 15 If the procedure is being carried out with the pump fitted to the engine, refit the injector pipes tightening their union nuts to the specified torque setting. Reconnect the battery and refit the air inlet ducting. 16 Start the engine, and check for any leakage at the luel unions. To enable the engine to start it may be necessary to loosen the injector union nuts while turning tho engine on the starter motor in order to purge trapped air. 17 Check and if necessary adjust the idle speed as described in Chapter 1B.
8.4 Removing the injection pump timing inspection plug (Lucas)
8 injection timing ^ (Lucas fuel injection pump) - ^ checking
and
adjustment ^
Caution: Some of the injection pump settings and access plugs may be sealed by the manufacturers at the factory, using paint or locking wire and lead seo/s. Do not disturb the seals if the vehicle Is still within the warranty period, otherwise tho warranty will be Invalidated. Also do not affempf the timing procedure unless accurate instrumentation is available.
Note: To check the Injection pump timing a speciai timing probe and mounting bracket Is required. Without access to this piece of equipment, injection pump timing should be entrusted to a Fiat dealer or other suitably equipped specialist. 1 If the injection timing is being checked with the pump tn position on the engine, rather than as part of the pump refitting procedure, disconnect the battery negative terminal (refer to Disconnecting the battery in the Reference Section of this manual), and remove the air inlet ducting from the front of the engine. 2 Unscrew the union nuts and disconnect the injector pipes from the Injection pump and In-jectors. Counterhold the unions on the pump, while unscrewing the pipe-to-pump union nuts. Remove the pipes as a set. Cover open unions to keep dirt out. using smalt plastic bags, or fingers cut from discarded (but clean!) rubber gloves. 3 Referring to Chapter 2C, set the engine at TDC on cylinder No 1, then turn the crank-shaft backwards (anti-clockwise) approx-imately a quarter of a turn. 4 Unscrew the access plug from the guide on the top of the pump body and recover the sealing washer (soe Illustration). Insert the special liming probe Into the guide, making sure it Ib correctly seated against the guide seating washer surface. Note: The timing probe must be seated against the guide sealing washer surface and not the upper lip of the guide for the measurement to be accurate. 5 Mount the bracket on the pump guide (using adapter tool) and securely mount the dial gauge {dial test indicator) In the bracket
expert22 fl/i* http://rutracker.org
Fuel system - diesel models 4C*3
8.5 Dial gauge (1), mounting bracket (2) and setting rod (3) In position on the injection pump (Lucas)
so that Its tip Is In contact with the bracket linkage (see Illustration). Position the dial gauge so that its plunger is at the mid-point of its travel and zero the gauge. 6 Rotate the crankshaft slowly in the correct direction of rotation (clockwise) until the crankshaft is positioned at TDC on No 1 piston with ell the sprocket timing marks aligned. 7 Check the reading on the dial gauge which should correspond to the value marked on the pump (there is a tolerance of * 0.04 mm). The timing value may be marked on a plastic disc attached to the front of the pump, or alternatively on a tag attached to Ihe pump control lever (see illustrations). 8 If adjustment is necessary, slacken the front pump mounting nuts/bolt and the raar mounting bolt, then slowly rotate tne pump body until the point is found where the specified reading is obtained on the dial gauge (access to the lower front bolt is gained through the hole in the injection pump sprocket). When the pump Is correctly positioned, tighten both its front mounting nuta/bolt and the rear bolt to their specified torque settings. 9 Withdraw the timing probe slightly, so that it
positioned clear of the pump rotor dowel. Rotato the crankshaft ihrough one and three quarter rotations in the normal direction of rotation. 10 Slide the timing probe back Into position ensuring that it Is correctly seated against the guide sealing washer surface, not (he upper Hp, then zero the dial gauge. 11 Rotate the crankshaft slowly in the correct direction ol rotation to the TDC position and recheck the timing measurement 12 If adjustment Is necessary, slacken the pump mounting nuts and bolt and repeat the operations in paragraphs 6 to 11. 13 When the pump timing is correctly set. remove the dial gauge and mounting bracket and withdraw the timing probe. 14 Refit the screw and sealing washer to the guide and tighten it securely.
8.7a Pump timing value (x) marked on plastic diso (Lucas)
15 If the procedure is being carried out as part of the pump refilling sequence, proceed as described in Section 5. 16 If the procedure is being carried out with the pump fitted to the engine, refit the injector pipes tightening their union nuts to the specified torque setting. Reconnect the battery and refit the air inlet ducting. 17 Start the engine, and check for any leakage at the fuel unions. To enable the engine to start it may be necessary to loosen tho injector union nuts while turning the engine on the starter motor in order to purge trapped air. 18 Check and If necessary adjust the Idle speed as described In Chapter 1B.
9 Fuel Injectors -testing, removal and refitting Sk ^
A
Warning: Exercise extreme caution when working on the fuel injectors. Never expose the hands or any part of the body to Injector spray, as the high working pressure can cause the fuel to pen ot rate the skin, with possibly fatal results. You are strongly advised to have any work which involves testing the injectors under pressure carried out by a dealer or fuel Injection specie list.
Testing 1 Injectors do deteriorate with prolonged uso, and it is reasonable to expect them to need reconditioning or renewal after 60 000 miles
8.7b Pump timing values marked on label (1) and tag (2) (Lucas)
(100 000 km) or so. Accurate testing, overhaul and calibration of the Injectors must be left to a specialist. A defective injector which Is causing knocking or smoking can be located without dismantling as follows. 2 Run the engine at a fast idle. Slacken each Injector union In turn, placing rag around the union to catch spilt fuel, and being careful not to exposa the skin to any spray. When tho union on the defective Injector is slackened, the knocking or smoking will stop.
Removal 3 Remove ihe air Inlet ducting from tho front part of the onglne. 4 Carefully clean around the Injectors and injector pipe union nuts. 5 Pull the leak-off pipes from the injectors (see illustration). 6 Unscrow the union nuts securing Ihe injector pipes to the fuel Injection pump. Counterhold the unions on the pump when unscrewing the nuts. Cover open unions lo keep dirt out, using small plastic bags, or fingers cut from discarded (but clean!) rubber gloves. 7 Unscrew the union nuts and disconnect the pipes from the ln|ectors, If necessary, the Injector pipes may be completely removed-Note carefully the locations of the pipe clamps, for use when refitting. Cover tho onds ot (he injectors, to prevent dirt ingress. 8 Unscrew the injectors using a deep socket or box spanner, and remove Ihem from the cylinder head (see Illustration). 9 Recover the tire seal washers from the cy-linder head and discard them (see illustration).
9.5 Disconnecting the Injector leak-off pipes 9.8 Removing an injector
6*1
Chapter 6
Clutch
Contents
Clutch - adjustment Clutch assembly - removal, inspection and refitting Clutch cable • removal and refitting Clutch hydraulic system - bleeding
Degrees of difficulty
2 Clutch master cylinder • removal and refitting 5 7 Clutch release mechanism - removal, Inspection and refitting 8 3 Clutch slave cylinder - removal and refitting 6 4 General information 1
Easy, suitable for
novice with little experience oi^
Faidy easy,
suitable for beginner
with
^
some
experience
Fairly difficult, suitable
for
competent ^
DIY
mechanic ^
Difficiit, suitable for ^ experienced DIY JR mechanic ^
V<*y difficult,
jk
suitable
for expert
DIY
« or professional ^
Specifications
General Type
Clutch pedal travel (cable-operated mechanism)
Friction plate diameter 8-valve petrol engines 16-valve petrol engines Diesel engines
Torque wrench setting Pressure plate retaining bolts
Single dry plate with diaphragm spring, cable- or hydraullcally-operated according to model 140.0 ± 5.0 mm
181.5 mm 190.0 mm 200.0 mm
Nm Ibf ft 16 12
1 General information
Vehicles with manual transmission are fitted with a pedal operated single dry plate clutch system. When the clutch pedal is depressed, effort is transmitted to the clutch release mechanism either mechanically by means of a cable, or hydraullcally by means of a master
2.5 Clutch cable adjustment
cylinder and slave cylinder. The release mechanism transfers effort to Ihe pressure plate diaphragm spring, which withdraws the pressure plate from the flywheel and releases the driven plate-Where applicable, the hydraulic fluid employed in the clutch system is the same as that used in the braking system, hence fluid is supplied to the master cylinder from a tapping on the brake fluid reservoir. The clutch hydraulic system must be sealed before work Is carried out on any of its components and then on completion, topped up and bled to remove any air bubbles.
2 Clutch - % adjustment §§ ^
Note: This procedure applies to models fitted with a cable-operated dutch
release
mechanism. No adjustment is possible on models with the hydrauHcaSy-operated system. 1 The clutch adjustment Is checked by measuring the clutch pedal travel. If a new cable has been fitted, settle it in position by depressing the clutch pedal at least thirty times. 2 Ensure that there are no obstructions
beneath the clutch pedal then measure the distance from the centre of the clutch pedal pad to the base of the steering wheel with the pedal In the at-rest position. Depress the clutch pedal fully to the floor, and measure the distance from the centre of the clutch pedal pad to the bata of the steering wheel. 3 Subtract the first measurement from the second to obtain the clutch pedal travel. If this is not with the range given in the Specifications at the start of this Chapter, adjust the clutch as follows. 4 The clutch cable Is adjusted by means of the adjuster nut on the transmission end of the cable. Access to the nut is from under the vehicle. Apply the handbrake then jack up the front of the vehicle and support on axle stands (see Jacking and vehicle support). 5 Working under the left-hand side of the engine compartment, slacken the locknut from the end of the clutch cable. Adjust the position of the adjuster nut. then depress the clutch pedal ten times and re-measure the dutch pedal travel. Repeat this procedure until the clutch pedal travel is as specified (see illustration). 6 Once the adjuster nut Is correctly positioned, and the pedal travel Is correctly set, securely tighten the cable locknut then lower the vehicle to the ground.
Braking system 9®5
2 Rotate the brake disc by hand and examine the whole of the surface area swept by the brake pads, on both sides ot the disc. Note: /( will bo necessary to remove the front brake pads to allow an adequate inspection of the disc's rear surface; refer to Section 2 tor details. 3 Typically, the disc surface will have a polished appearance and should be free from heavy scoring. Smooth rippling is produced by normal operation and does not indicate excessive wear. Deep scoring and cracks, however, are indications of more serious damage in need of correction. 4 If deep scoring Is discovered, it may be possible to have the disc reground to restore the surface, depending on the extent of the damage. To determine whether this is a feasible course of action, it will be necessary to measure the thickness of the disc, as described later. 5 Check the whole surface of the disc for cracks, particularly around the roadwheel bolt holes. A cracked disc mutt be renewed. 6 A ridge of rust and brake dust at the inner and outer edges of the disc, beyond the pad contact area is normal - this can be scraped tway quite easily. 7 Raised ridges caused by the brake pads eroding the disc material, however, are an indication of excessive wear. If close examination reveals such ridges, the oiicknoss of the disc must be measured, to usess whether it is still fit for use. 8 To measure the thickness of the disc, take readings at several points on the surface using a micrometer. In the area swept by the brake pads (see Illustration). Include any points where the disc has been scored: align me Jaws of the micrometer with the deepest ares of scoring, to get a true indication of the extent of the wear. Compare these ineasurements with the limits listed in the Specifications. If the disc has worn below its minimum thickness, at any point, it must be renewed. 9 If the discs are suspected of causing brake luddor, check the disc runout, using one of
me
following methods: Runout measurement -
DTI
gauge method 10 Refit the four roadwheel bolts, together
w.1h
one M14 plain washer per stud • this will ensure adequate disc to hub contact. Tighten te studs to 5 Nm (4 Ibf ft). 11 Clamp the DTI gauge to a stand and attach the stand, preferably via a magnetic oase. to the strut mounting bracket. Align the jauge so that its pointer rests upon the area of the dtsc swept by the brake pads, on an arc i mm from the outer edge of tho disc (soe illustration). 12 Zero the gauge and slowly rotate the disc trough one revolution, observing tho pointer rcovement. Note the maximum deflection recorded and compare the figure with that >«ted In Specifications.
4.8 Measuring brake disc thickness with a micrometer
Runout measurement -feeler blade method 13 Use the feeler blades to measure the clearance between the disc and a convenient fixed point, such as the disc backplate. Rotate the disc and measure the variation in clearance at several points around the disc, Compare the maximum figure with that listed in Specifications. 14 If the disc runout Is outside of its specified tolerance, first check that the hub Is not worn (see Steering and suspension check in Chapter 1A or 1B). If the hub is In good condition, remove the disc (as described later in this Section), rotate it through 180° and refit it. This may improve the seating and eradicate Ihe excessive runout. 15 If the runout is still unacceptable, then It may be possible to restore the disc by regrinding; consult your Fiat dealer or a machine shop for a professional opinion - it may prove more economical to purchase a new disc. If the disc cannot be reground, then it must be renewed.
Removal 16 Mark the relationship between the disc and the hub with chalk or a marker pen, to allow correct refitting. 17 To allow the disc to be removed, undo the two bolts securing (he brake caliper mounting bracket to the hub carrier (see illustration 3.7). Withdraw the brake caliper and mounting bracket assembly, complete with brake pads, from the hub carrier, and hang it from a rigid point on the suspension, using v/lre or a
4.18a Slacken and remove the disc locating studs ...
4.11 Brake disc runout measurement - DTI gauge method
cable-tie. Oo not allow it to dangle freely as this will strain the brake hose. 18 Slacken and remove the disc locating stud(s). Support the disc as you do this and lift it off as it becomes free (see illustrations). 19 Remove the polished glaze from the surface of the disc with sand/emery paper. Use small, circular motions to avoid producing a directional finish on the surface.
Refitting 20 If a new disc Is being fitted, remove the protective coating from the surface U9ing an appropriate solvent. 21 Locate Ihe disc on ihe hub so that the roadwheel bolt and locating stud holes are all correctly lined up; use the alignment marks made during removal. If the disc is being removed in an attempt to improve seating and hence runout, turn the disc through 180° and then refit it. 22 Refit the locating stud and retaining screw, tightening them securely. 23 Re-check the disc runout, using one of the methods described earlier in this Section. 24 Refil the brake caliper and mounting bracket assembly to the hub carrier. Coat the threads of the mounting bolts with locking compound, then tighten them to the specified torque. 25 Depress the brake pedal several times to bnng the brake pads into contact with the disc. 26 Refit the roadwheel and lower the vehicle to the ground. Tighten the roadwheel bolts to the specified torque. 27 Check the hydraulic fluid level as described in Weekly checks.
4,18b ... and lift off the disc as It becomes free