Exhaust FIAT PUNTO 1998 176 / 1.G Owner's Manual
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Page 47 of 225

Every 20 000 miles - diesel models ib.h
18
Valve clearance check and
adjustment
1 The Importance of having the valve clearances correctly adjusted cannot be Distressed, as they vitally affect the performance of the engine. Adjustment should only be necessary when the valve gear nas become noisy, after engine overhaul, or when trying to trace the cause of power loss. The clearances are checked as follows. The engine must be cold for the check to be ttcurate. 2 Apply the handbrake then jack up the right-hand front of the vehicle and support on an axle stand (see Jacking and vehicle support). Engage 4th gear. The engine can now be rotated by turning the right-hand front roadwfteei. 3 Remove ail four glove plugs as described In Chapter 5C. 4 Remove the air cleaner cover and air duct
then
remove the camshaft cover as described
in
Chapter 2C. 6 Each valve clearance must be checked wnen the high point of the cam is pointing directly upward away from the cam follower. 6 Check the clearances in the firing order 1-3-4-2, No 1 cylinder being at the timing belt end of the engine. This will minimise the amount of crankshaft rotation required. 7 Insert the appropriate feeler blade between
the heel
of the cam and the cam follower shim of the First valve (see Illustration). If necessary alter the thickness of the feeler blade until it is a stiff, sliding fit. Record the thickness, which will, of course, represent the
vafve
clearance tor Ihis particular valve. 8 Turn the engine, check the second valve devance and record it. t Repeat the operations on all the remaining valves. recording their respective clearances. 10 Remember that the clearance for inlet and exhaust valves differs - see Specifications. Counting from the timing cover end of the
engine,
the valve sequence is: Wef 2-4-5-7 Etfiat/sf 7-3-6-8
11 Where clearances are incorrect the particular shim will have to be changed. To remove the shim, turn the crankshaft until the high point of the cam is pointing directly upward. The cam follower will now have to bo depressed so that the shim can be extracted. Special tools are available from your Fiat dealer to do the job. otherwise you will have to make up a forked lever to locate on the rim of ihe cam follower. This must allow room for the shim to be prised out by means of the cut-outs provided in the cam follower rim (see illustration). 12 Once Ihe shim is extracted, establish Its thickness and change it for a thicker or thinner one to bring the previously recorded clear-ance within specification, For example, if the measured valve clearance was 1.27 mm too great, a shim thicker by this amount will be required. Conversely, if the clearance was 1.27 mm too small, a shim thinner by this amount will be required. 13 Shims have their thickness (mm) engraved on ihem; although the engraved side should be fitted so as not to be visible, wear still occurs and often obliterates the number. In this case, measuring their thickness with a metric micrometer is the only method to establish their thickness (see illustration). 14 In practice, if several shims have to be changed, they can often be interchanged, so avoiding the necessity of having to buy more new shims than is necessary. 15 If more than two or three valve clearances are found to be incorrect, it will be more convenient to remove the camshaft lor easier removal of the shims. 16 Where no clearance can be measured, even with the Ihinnest available shim in position, the valve will have to be removed and the end of its stem ground off squarely. This will reduce its overall length by the minimum amount to provide a clearance. This job should be entrusted to your dealer as it is important to keep the end of the valve stem square. 17 On completion, refit the camshaft cover and gasket, air cleaner and duct, and glosvplugs. 18 Lower the vehicle to the ground.
19 Hinge and lock lubrication
I
1 Lubricate the hinges of the bonnet, doors and tailgate with a light general-purpose oil. Similarly, lubricate all latches, locks and lock stnkers. At the same time, check the security and operation of all the locks, adjusting them if necessary (see Chapter 11). 2 Lightly lubricate the bonnet release mechanism and cable with a suitable grease.
20 Headlight beam adjustment
I
1 Accurate adjustment of the headlight beam Is only possible using optical beam-setting equipment, and this work should therefore be carried out by a Fiat dealer or service station with the necessary facilities. In an emergency, however, the following procedure will provide an acceptable light pattern. 2 Position the car on a level surface with tyres correctly inflated, approximately 10 metres in front of, and at right-angles to, a wall or garage door. 3 Draw a horizontal tine on the wall or door at headlamp centre height. Draw a vertical line corresponding to the centre line of the car. then measure off a point either side of this, on the horizontal line, corresponding with the headlamp centres. 4 Switch on the main beam and check that the areas of maximum Illumination coincide with the headlamp centre marks on the wall. If not, turn the adjustment screw located on the upper Inside edge of the headlight unit to adjust the beam laterally, and the adjustment screw located on the upper outside edge of the headlight unit to adjust the beam vertically. On models with electric headlight adjustment, make sure that it Is set at its basic setting before making the adjustment,
Page 48 of 225

1B«12 Every 20 000 miles - diesel models
21 Road test
Instruments and electrical equipment 1 Check the operation of atl instruments and electrical equipment. 2 Make sure that all instruments read correctly, and switch on all electrical equipment rn turn, to check that It functions properly. Steering and suspension 3 Check for any abnormalities in the steering, suspension, handling or road feel. 4 Drive the vehicle, and check that there are no unusual vibrations or noises. 5 Check that the steering feete positive, with no excessive sloppiness, or roughness, and check for any suspension noises when cornering and driving over bumps. Drivetrain 6 Check (he performance of the engine, clutch, transmission and driveshafts.
7 Listen for any unusual noises from the engine, clutch and transmission. 8 Make sure that the engine runs smoothly when Idling, and that there is no hesitation when accelerating. 9 Check that the clutch action is smooth and progressive, that tho drive is taken up smoothly, and that the pedal travel Is not excessive. Also listen for any noises when the clutch pedal is depressed. 10 Check that all gears can be engaged smoothly without noise, and that the gear lever action Is not abnormally vague or notchy. 11 Listen for a metallic clicking sound from ihe front of the vehicle, as the vehicle « driven slowly In a circle with the steering on full-lock. Carry out this check In both directions, if a clicking noise is heard, this Indicates wear in a driveshaft |oinl, in which case renew the joint if necessary.
Check the braking system 12 Make sure that the vehicle does not pull to one side when braking, and that the wheels do not lock prematurely when braking hard.
13 Check that there Is no vibration through the steering when braking. 14 Check that the handbrake operates correctiy without excessive movement of th« lever, end that it holds the vehicle stationery on a slope. 15 Test the operation of the brake servo unit as follows. With the engine off, depress the footbrake four or five times to exhaust the vacuum. Hold the brake pedal depressed, then start the engine. As the engine starts, there should be a noticeable give In the brake pedal as vacuum builds up. Allow the engine to run for at least two minutes, and then switch it off. If the brake pedal is depressed now, it should be possible to detect a hiss from the servo es the pedal is depressed. After about four or five applications, no fimher hissing should be heard, and the pedal should feel considerably harder. Note: The vacuum for the servo unit is provided by the vacuum pump mounted on the left-hand end of t/ie cylinder head.
Every 30 000 miles (45 000 km) or 3 years
22 Manual transmission oil level check ;5§
1 Park the vehicle on a level surface. If possible over an inspection pit or on a ramp as the filler/level plug is best reached from under Ihe engine compartment. The oil level must be checked before the car Is driven, or at least 5 minutes after the engine has been switched off. If the oil is checked Immediately after driving the car. some of the oil will remain distnbuted around the transmission compo-nents, resulting In an inaccurate level reading. 2 Wipe clean the area around the filler/level plug, which is situated on tho front of the
transmission (see illustration). Using an Allen key. unscrew the plug and clean it. 3 The oil level should reach the lower edge of the filler/level hole. A certain amount of oil will have gathered behind the filler/level plug, and will trickle out when it is removed; this does not necessarily Indicate that the level Is correct. To ensure that a true level Is established, wait until the Initial trickle has stopped, then add oil as necessary until a trickle of new oil can be seen emerging. The level will be correct when the flow ceases; use only good-quality oil of the specified type-Make sure that the vehicle Is completely level when checking the level and do not overfill. 4 When the level is correct refit and tighten the plug and wipe away any spilt oil.
22.2 Transmission filler/level plug location
Every 40 000 miles (60 000 km) or 4 years
23 Rear brake shoe check
1 Chock the front wheels then jack up the rear of the car and support It on axle stands (see Jacking and Vehicle Support), Remove the rear roadwhecla. 2 Using the inspection hole at the edge ot the brake drum, check that the linings are not worn below the minimum thickness given In the Spec ifi cat Ions (see Illustration). If necessary use a torch. 3 If the friction material on any shoe is worn down to the specified minimum thickness or iess. all four shoes must be renewed as a set, 4 At the same time check for signs of brake fluid leakage. 5 For a comprehensive check, the brake
drum should be removed and cleaned. This will allow the wheel cylinders to be checked, and the condition of the brake drum itself to be fully examined (see Chapter 9). 8 Refit the rubber plugs then lower the car to the ground.
24 Timing belt renewal
Refer to Chapter 2C. Note: Although the normal interval for timing belt
ranees/a!
is 70 000
mHes
(105 000
km),
it is strong recommended that the interval is reduced on vehicles which are subjected to intensive use, ie, mainly short journeys or a lot of stop-start driving. The actual belt renewal interval is therefore very much up to tho individual owner.
That being said, it is highly recommended to err on the side of safety, and renew (he belt at
this
earlier interval, bearing in mind the drastic consequences resulting from belt fetfure.
23.2 Check the thickness of the shoe friction material through the hole on the edge of the drum (arrowed)
Page 52 of 225

2A*10 SOHC (8-valve) petrol engine in-car repair procedures
Torque wrench settings Nm
IM
ft Camshaft cover 8 6 Camshaft sprocket 70 52 Cylinder head; Stage 1 30 22 Stage 2 Angle-lighten a further 90° Siege 3 Angle-tighten a further 90B Crankshaft sprocket centre bott 100 74 Engine mounting bolt: M10X1.25 69 44 MB 25 18 Engine mounting nut (M10x 1.25) 60 44 Flywheet/driveplate 44 32 Sump 10 7 Timing belt tensJoner 28 21
1 General information
Using this Chapter Chapter 2 is divided Into four Parts: A. 8. C and D. Repair operations that can be carried out with the engine in the vehicle are described in Part A. SOHC (8-valve) petrol engines, Part B. DOHC (18-valve) petrol engines and Part C, diesel engines. Part 0 covers the removal of the engine/transmission as a unit, and describes the engine dismantling and overhaul procedures. In Parts A, 9 and C, the assumption Is made lhat the engine is Installed in the vehicle, with sll ancillaries connected. If the engine has been removed for overhaul, the preliminary dismantling Information which precedes each operation may be ignored.
Engine description Throughout this Chapter, engines are identified by their capacities. A listing of all engines covered, together with their code letters, is given in the Specifications. The engines covered In this Part of Chapter 2 are water-cooled, single overhead camshaft, in-line four-cylinder units, with cast Iron cylinder Mocks and aluminium-alloy cylinder heads. All are mounted transversely at the front ot the vehicle, with the transmission bolted to the left-hand side of the engine, The cylinder head carries the camshaft which is driven by a toothed timing belt and runs In three bearings. It also houses the inlet and exhaust valves, which are closed by single coil springs, and which run in guides pressed Into the cylinder head. The camshaft actuates the vatves directly via cam followers mounted in the cylinder head. Adjustment of the valve clearances is by means of shims located on top of the followers. The cylinder head contains Integral oitways which supply and lubricate the tappets. The crankshafl Is supported by five main bearings, and endftoat is controlled by a thrust bearing fitted to the upper section of the centre main bearing.
Engine coolant is circulated by 8 pump, driven by the timing belt. For details of the cooling system, refer to Chapter 3. Lubricant is circulated under pressure by a pump, driven from ihe front of the crankshaft. Oil Is drawn from the sump through a strainer, and then forced through an externally-mounted, replaceable screw-on filter. From there, It is distributed to the cylinder head, where It lubricates the camshaft journals and tappets, and also to the crankcase, where il lubricates the main bearings, connecting rod big and smell-ends, gudgeon pins and cylinder bores. On 1242 cc engines, oil jets are fitted lo the base of each cylinder bore -these spray oil onto the underside of the pistons, to Improve cooling.
Repair operations possible with the engine in the car The following work can be carried out with the engine in the car a) Compression pressure - testing b) Auxiliary drivebelt - removal and refitting (refer to Chapter 1A) c) Vatve clearances - checking and adjustment (refer to Chapter I A) d) Camshaft cover - removal and refitting e) Timing belt and covens - removal and refitting f) Timing belt tensioner and sprockets -removal and refitting g) Cylinder head - removal and refitting' h) Camshaft and cam followers • removal and refitting' t) Camshaft oil seal - renews/ j) Crankshaft oil seals - renewal k) Flywheel/dnvepfate • removal, inspection and refitting l) Engine mountings - inspection and renewal m)Sump - removal and refitting n) Oil pump and pick-up tube assembly
•
removai. inspection and refitting *Cylinder head dismantling procedures are detailed In Chapter SO, with details of camshaft and cam follower removal. Note: It is possible to remove the pistons and connecting rods (after removing the cylinder head and sump) without removing the engine. However, this is not recommended. Work of
this nature is more easily and thoroughly completed with the engine on the bench, as described In Chapter 2D.
2 Location of
TDC
on % No
1
cylinder
General Information 1 The camshaft Is driven by the crankshaft, by means of sprockets and a timing belt. Both sprockets rotate In phase with each other and this provides the correct valve timing as the engine rotates. When (he liming belt is removed during servioing or repair, it Is possible for the camshaft and crankshaft to rotate Independently of each other and the correct valve timing Is then lost. 2 The design of the engines covered In this Chapter are such lhat potentially damaging piston-to-valve contact may occur if the camshaft is rotated when any of the pistons are stationary at, or near, the top of their stroke. 3 For this reason it is important lhat Ihe correct phasing between the camshaft and crankshaft is preserved whilst the timing belt Is off the engine. This is achieved by setting the engine In a reference position (known as Top Dead Centre or TDC) before the timing belt Is removed and then preventing the camshaft and crankshaft from rotating until the belt is refitted. Similarly, if ths engine has been dismantled for overhaul, the engine can be set to TOC during reassembly to ensure that Ihe correct shaft phasing is restored. 4 TDC is the highest point In the cylinder that each piston reaches as the crankshaft turns. Each piston reaches TDC at Ihe end of the compression stroke and again at the end of the exhaust stroke. However, for the purpose of timing the ongine. TDC refers to the position of No 1 piston at the end of Its compression stroke. On ail engines In this manual, No 1 piston (and cylinder) Is at the timing belt end of the engine. 5 The camshaft sprocket Is equipped with a marking which, when aligned with a reference marking on the cylinder head, indicates that the camshaft is correctly positioned for cyl-inder No 1 al TDC on its compression stroke.
Page 53 of 225

2A*10 SOHC (8-valve) petrol engine in-car repair procedures
2.11 Unscrewing the crankshaft pulley bolts
6 Itae crankshaft sprocket Is also equipped •nth a timing mark - when this is aligned with 3relarence marking on the oil pump cover.
Hie
engine is set with cylinders No 1 and 4 at
TDC.
Note that it is the camshaft positioning that determines whether a cylinder is on its comcression or exhaust stroke.
Location
of TDC on cylinder No 1 7 Remove the air cleaner and ducting as descnbed in Chapter 4A or 4B. Remove the
spark
plug from No 1 cylinder as described in Chapter 1A. 8 Firmly apply the handbrake, then |ack up
the
front of the car and support it securely on iiia stands (see Jacking end vehicle support). 9 Remove the auxiliary drivebelt(s) as described in Chapter 1A. 10 Unbolt and remove the timing belt cover. Mole the bolt located at the bottom of the
coven
this can be easily overlooked. 11 Undo the three bolts and remove the crankshaft pulley from the sprocket (see {lustration). 12 Turn Ihe engine in its normal direction of rotation (using a socket or spanner on Ihe crankshaft sprocket centre bolt) until pressure an be felt at No
1
cylinder spark plug hole.
1 flfliyflg^ Remove all four spark plugs; "••"•1 this will make the engine HlNTl easier to turn; refer to Chapter 1A for details.
13 Continue turning the engine until the crahaft sprocket TDC timing mark is aligned with the mark on the cylinder head and the crankshaft sprocket timing mark is aligned with the mark on the oil pump cover (see ilustrations). 14 The engine is now set at TDC for No 1 cylinder on compression.
3 Cylinder compression test t ^
1 When engine performance Is down, or if misfiring occurs which cannot be attributed to tne ignition or fuei systems, a compression isst can provide diagnostic clues as to the
2.13a Camshaft sprocket and cylinder head TDC timing marks (arrowed) aligned -shown with timing belt removed engine's condition. II the test is performed regularly, it can give warning of trouble any other symptoms become apparent. 2 The engine must be fully warmed-up to normal operating temperature, the battery must be fufly charged, and all the spark plugs must be removed (Chapter 1A). The aid of an assistant will also be required. 3 Disable the ignition system by dis-connecting the LT wiring plug to the ignition coils. 4 Fit a compression tester to the No 1 cyl-inder spark plug hole - the type of tester which screws into the plug thread is to be preferred, 5 Have the assistant hold the throttle wide open, and crank the engine on the starter motor; after one or two revolutions, the compression pressure should build up to a maximum figure, and then stabilise. Record the highest reading obtained. 6 Repeat the lest on the remaining cylinders, recording the pressure in each. 7 All cylinders should produce very similar pressures; any excessive difference indicates the existence of a fault. Note that the compression should build up quickly in a healthy engine; low compression on the first stroke, followed by gradually increasing pressure on successive strokes, indicates worn piston rings. A low compression reading on the first stroke, which does not build up during successive strokes, indicates leaking valves or a blown head gasket (a cracked head could also be the cause). 8 If the pressure in any cylinder is very low. carry out the following test to isolate the cause. Introduce a teaspoonful of clean oil into that cylinder through its spark plug hole and repeat the test. 9 If the addition of oil temporarily improves the compression pressure, this indicates that bore or piston wear Is responsible for the pressure loss. No improvement suggests that leaking or burnt valves, or a biown head gasket, may be to blame. 10 A low reading from two adjacent cylinders is almost certainly due to the head gasket having blown between them; the presence of coolant in the engine oil will confirm this. 11 If one cylinder is about 20 percent lower
2.13b Crankshaft sprocket and oil pump cover TDC timing marks (arrowed) aligned
than the others and Ihe engine has a slightly rough idle, a worn camshaft lobe could be the cause. 12 On completion of the test, refit the spark plugs and reconnect the ignition LT wiring plug.
4 Timing belt and covers -removal and refitting ^
Note: Fiat specify the use of a special timing belt fens/on measuring toot to correctly set tho timing belt tension. If access to this equipment cannot be obtained, an approximate setting can be achieved using the method described below. It the method described is used, the tension must be checked using the special tool at the earliest possible opportunity. Do not drive the vehicle over large distances, or use high engine speeds, until the belt tension is known fo be correct. Refer to a Fiat dealer foradvSce.
General information 1 The function of the timing belt is to drive Ihe camshaft and coolant pump. Should the belt slip or break In service, the valve timing will be disturbed and piston-to-valvo contact will occur, resulting in serious engine damage, 2 The timing belt should be renewed ai the specified intervals (see Chapter 1A), or earlier if it is contaminated with oil. or if it is at all noisy in operation (a scraping noise due to uneven wear). 3 If the timing belt is being removed, it Is a wise precaution to check the condition of the coolant pump at the same time (check for signs of coolant leakage). This may avoid the need to remove the timing belt again at a later stage, should the coolant pump fall.
Removal 4 Firmly apply the handbrake, then jack up the front of the car and support it securely on axle stands (see Jacking and vehicle support). Remove the right-hand front road wheel. 5 Remove the air cleaner and air ducting as described in Chapter 4A or 46. 6 Remove the auxiliary drivebelt(s) and the spark plugs as described in Chapter 1A.
2A
Page 56 of 225

2A*10 SOHC (8-valve) petrol engine in-car repair procedures
6.3 Camshaft cover gasket
not attempt to lover it ofl • instead free >t by working around the cover and lapping it lightly with a soft-faced mallet, 3 Recover the camshaft covor gasket {see Illustration). Inspect the gasket carefully. And renew It If damage or deterioration is evident. 4 Clean the mating surfaces of the cylinder head and camshaft cover thoroughly, removing all traces of oil and old gasket - take care to avoid damaging the surfaces as you do this.
Refitting 5 Locate a new gasket on the cylinder head and make sure it Is correctly seated. 6 Lower the cover onto the gasket making sure the gasket is not displaced. 7 Insert Ihe mounting bolts and tighten them progressively to the specified torque. 8 Refit the air cleaner assembly and inlet duct with reference to Chapter 4A or 48.
7 Camshaft oil seal • renewal I
1 Remove the timing beft and camshaft sprocket as described in Sections 4 and 5, 2 Using a suitable hooked Instrument, remove the oil seal from the cylinder head taking care not to damage the surface of (he camshaft. 3 Clean the seating in the cylinder head and the end of the camshaft. To prevent damage to the new olf seal as it is being fitted, wrap some adhesive tape around the end of the camshaft and lightly oil it.
4 Dip the new oil seal In oil then locate it over the camshaft making sure that the sealing lips are facing inwards, 5 Using a suitable tubular drift, drive the oil seal squarely Into the cylinder head. Remove the adhesive tape. 8 Refit the camshaft sprocket and liming belt wtth reference to Sections 5 and 4.
8 Crankshaft oil seals - ^ renewal S
Front (right-hand side) oil seal 1 The fronl oil seal is located in tho oil pump on the front of the crankshaft. Remove the timing belt as described in Section 4 and the crankshaft sprocket as described in Section 5. 2 Using a hooked instrument, remove the oil seal from the oil pump casing taking care not to damage the surface of the crankshaft. 3 Clean Ihe seating in the housing and the surface of the crankshaft. To prevent damage to the new oil seal as it is being fitted, wrap some adhesive tape around the end of the crankshaft and lightly oil it. 4 Dtp the new oil seal In oil then offer It up 1o the oil pump casing making sure that tho sealing lips are facing Inwards. G Using a suitable tubular drift, drive the oil seal squarely into the casing. Remove the adhesive tape. 6 Refit the crankshaft sprocket and timing belt with reference to Sections S and 4.
Rear {left-hand side) oil seal Note: The following paragraphs describe renewal of the rear oil seal leaving the housing in position. Refer to Chapter 2D for details of removing the housing. 7 Remove the fiywheel/drlveplate as described in Section 10. 8 Using a suitable hooked instrument, remove the oil seal from the rear oil seat housing taking care not to damage the surface of Ihe crankshaft. 9 Clean the seating In the nousing and the surface of the crankshaft. Check the crankshaft for burrs which may damage the sealing lip of the new seal, and If necessary use a fine file to remove them,
10 Dip the new seal In clean engine oil and carefully locate it over the crankshaft rear flange making sure that It is the correct way round. 11 Progressively tap the oil seal Into the housing keeping It square to prevent distortion. A block of wood is useful for this purpose. 12 Refit the fiywheet/drlvepiate with refer-ence to Section 10.
9 Cylinder head -removal and refitting I
i Removing the timing belt inner covers 9.12 Removing the cylinder head
Removal 1 Disconnect the battery negative termine! (refer to Disconnecting the battery In the Reference Section of this manual). 2 Drain the cooling system as described In Chapter 1A. then remove the air cleaner and ducting as described in Chapter 4A or 48. 3 Disconnect the accelerator cable and controls from the throttle housing. 4 Disconnect the fuel hoses. 5 Disconnect the coolant and vacuum hoses from the cylinder head and inlet manifold. 6 Disconnect all electrical leads noting their location. 7 Remove the Ignition colls with reference to Chapter 58. 8 Remove the timing belt as described in Section 4, then unbolt end remove the timing belt inner covers (see Illustration). 9 Unbolt and remove the Inlet manifold, complete with throttle housing. On MPI models unbolt the fuel rail. 10 Unbolt the exhaust manifold from th» cylinder head, and tie it to the front of tto engine compartment. If preferred remove the manifold completely by unbolting Ihe downpipe. Also disconnect iha downpipe bracket. 11 Unscrew the cylinder head bolts hall a turn at a time in the reverse order to thai shown In illustration 9.24b. When the bolts in free, remove them wtth their washers. 12 Lift the cylinder head from Ihe block (see Illustration), if It is stuck tight Insert pieces
of
wood Into the exhaust or Inlet ports, and use them as levers to rock the head off the block. On no account drive levers into the gasket joint, nor attempt to tap the head sideways,
as
It Is located on positioning dowels. 13 Remove and discard the cylinder heed gasket and the manifold gaskets. 14 The cylinder head can be dismantled after removing the camshaft and cam followers as described in Chapter 2D. 15 If the valves have been ground-in, the valve clearances will require adjusting, as described In Chapter 1A. This should be dons before the cylinder head is refitted to the engine.
Page 57 of 225

2A*10 SOHC (8-valve) petrol engine in-car repair procedures
Preparation for refitting 16 The mating faces of the cylinder head and cylinder block must be perfectly clean before
refitting
the head. Use a hard plastic or wooden scraper to remove all traces of gasket and carbon; also clean the piston crowns. Take padicular care when cleaning the piston crowns as the soft aluminium alloy is easily damaged. Make sure that the carbon is not afowed to enter the oil and water passages -Ihs is particularly important for the lubrication
system, as
carbon could block the oil supply to
Ihe
engine's components. Using adhesive tape
and
paper, seal the water, oil and bolt holes in tf« cylinder block. To prevent carbon entering twgap between the pistons and bores, smear
a
iittte grease in the gap. After cleaning each piston, use a small brush to remove all traces of grease and carbon from the gap, then wipe away the remainder with a clean rag. Clean all
ttie pistons
in the same way. 17 Check the mating surfaces of the cylinder block and the cylinder head for nicks, deep scratches and other damage. If slight, they may be removed carefully with a file, but if (xcassive, machining may be the only alternative to renewal. If warpage of the Cytodar head gasket surface is suspected, use a straight-edge to check it for distortion.
Refer
to Part 0 of this Chapter if necessary. 18 Check the condition of the cylinder head
MRS.
and particularly their threads, whenever
they are
removed. Wash the bolts In a suitable solvent, and wipe them dry. Check each bolt for any sign of visible wear or damage, renewing them if necessary.
Refitting 18 Before refitting Ihe assembled cylinder head, make sure that the head and block mating surfaces are perfectly clean, and that
the
bolt holes in the cylinder block have been
mopped
out to clear any oil. 20 Check that the camshaft and crankshaft sprocket timing marks are still aligned with tteir respective cylinder head and oil pump covtr marks as described in Section 2. 21 The new gasket should not be removed from its nylon cover until required for use. Fit
the
gasket dry, and make sure that the mating surfaces on the head and block are perfectly dean.
9.22a Place the cylinder head gasket on the cylinder block ... 22 Place the gasket on the cylinder block so that the word ALTO can be read from above (see illustrations). 23 Lower the cylinder head onto the block so that It locates on the positioning dowel. 24 The cylinder head bolt threads must be clean. Dip the bolts In engine oil. and allow them to drain for thirty minutes. Screw the bolls in finger-tight then working progressively and in the sequence shown, tighten all the cylinder head bolts to the Stage 1 torque setting given In the Specifications, using a torque wrench and a suitable socket. With all the bolts tightened to their Stage 1 setting, working again in the specified sequence, first angle-tighten the bolts through ihe specified Stage 2 angle, then again through the Stage 3 angle, using a socket and extension bar. It is recommended that an angle-measuring gauge is used dunng this stage of tightening, to ensure accuracy (see Illustrations). 25 Refit the inlet manifold and throttle body using a new gasket (refer to Chapter 4A or 4B). 28 Refit the exhaust manifold using a new gasket. Tighten all nuts. Reconnect the exhaust downplpe bracket. 27 Refit the timing belt inner covers and tighten the bolls. 28 Refit the timing belt, and tension It as described in Section 4. Refit the timing belt outer cover. 29 Refit the ignition colls and camshaft cover. 30 Reconnect all hoses, electrical leads and controls referring the relevant Chapters of this manual. 31 Fit the air cleaner and ducting.
9.22b ... so that the ALTO marking can be read from above 32 Reconnect the battery then fill and bleed the cooling system as described in Chapter 1A.
10 Flywheel/driveplate • ^ removal, inspection
and
refitting ^
Removal 1 Remove the transmission as described in Chapter 7A or 7B. On manual transmission models also remove the clutch (Chapter 6). 2 Mark the position of the flywheel/driveplate with respect to the crankshaft using a dab of paint. Note thai on some models although there is only one location dowel on the flywheel/driveplate there are two holes in the eno of the crankshaft and it is therefore possible to locate Ihe flywheel 180n out. The flywheel/driveplate must now be held stationary while the bolts are loosened. A home-made locking tool may be fabricated from a piece of scrap metal and used to lock the ring gear. Bolt the tool to one of the transmission bellhousing mounting holes. 3 Unscrew then remove the mounting bolts then lift off the flywheel/driveplate. Recover the spacer plate on manual transmission models. Discard the fiywheet/drivepiate boils; new ones must be used on refitting.
Inspection
Manual transmission models 4 If the flywheel's clutch mating surface is deeply scored, cracked or otherwise damaged, the flywheel must be renewed.
JEaMKA. mar 9.24c Using an angle gauge to tighten the cylinder head bolts to their second and third stage torque settings
L
Page 58 of 225

2A*10 SOHC (8-valve) petrol engine in-car repair procedures
10.10 Tighten the flywheel bolt to the specified torque However, it may be possible lo have it surface*ground; seek (he advice of a Rat dealer or engine reconditioning specialist, 5 If Ihe ring gear is badly worn or has missing teeth, the flywheel must be renewed. Automatic transmission models 6 Check the driveplate for signs of damage and renew it if necessary. If the ring gear is badly worn or has missing teeth, the driveplate must be renewed.
Refitting 7 Clean the mating surfaces of the flywheel/ drivoplate and crankshoft. Remove any remaining locking compound from the threads of the crankshaft holes, using the correct-size tap. if available.
ft a suitable tap fs not . # | available, cut two slots down jHlNTI
toe
threads of ono of the old bolts with a hacksaw, and use the bolt to remove the locking compound from the throads.
8 If the new retaining bolts are not supplied with their threads already pre-coated, apply a suitable thread-locking compound to the threads of each bolt. 9 Offer up the fiywhee'/drlveplate lo the crankshaft, using the alignment marks made during removal, and fit the new retaining bolts (together with the spacer plate on manual transmission models), 10 Lock the flywheel/dnveplate using Ihe method employed on dismantling, and tighten
the retaining bolts to the specified torque (see illustration), 11 Refit the clutch on manual transmission models as described in Chapter 6. 12 Relit the transmission as described In Chapter 7A or 78.
11 Engine mountings • inspection and renewal
inspection 1 Firmly apply the handbrake, then jack up the front of the car and support it securely on axle stands (see Jacking and vehicle support). 2 Check Ihe mounting rubbers to see if they are cracked, hardened or separated from the metal at any point; renew the mounting if any such damage or deterioration is evident. 3 Check that all the mounting's fasteners are securely tightened; use a torque wrench to check II possible. 4 Using a large screwdriver or a crowbar, check for wear In the mounting by carefuliy levering against It to check for free play. Where this is not possible enlist the
aid
of
an
assistant to move the engina/transmission back
and
forth, or from s»de to side, while you watch the mounting. While some free play rs to bo expected even from new components, excessive wear
should
be obvious. If excessive free play is found, check first that the fasteners are correctly secured, then renew any worn components as described below.
Renewal Right-hand mounting 5 Firmly apply the handbrake, then jack up the front of the car and support it securely on axle stands (see Jacking and vehicle support). 8 Place a trolley jack beneath the right-hand side of Ihe engine, with a block of wood on the jack head. Raise the jack until it is supporting the weight of the engine. 7 Unscrew the nut securing the engine bracket to the mounting. 8 Lower the engine slightly then unboll the mounting from the body. 9 Locate the new mounting on the body, insert the bolts and tighten to the specified torque.
10 Raise tne engine and locate the bracket on the mounting. Refit tho nut and tighten lo the specified torque. 11 Remove the trolley jack and lower the vehicle to the ground. Left-hand mounting 12 Firmly apply the handbrake, then jack up the front of the car and support it securely on axle stands (see Jacking and vehicle support) 13 Place a trolley |sck beneath the transmission, with a block of wood on the jack head. Raise the jack until it is supporting tne weight of the engine/transmission. 14 Unscrew Ihe bolts securing the left-hand mounting to tho body. 15 Unscrew the nut securing ihe mounting to the transmission bracket and recover the washers. 16 Lower the transmission sufficiently to remove the mounting from the transmission bracket. 17 Locate the new mounting In the trans-mission bracket and refit the nut and washers. Tighten the nut to the specified torque. 18 Raise the engine and refit the mounting-to-body bolts. Tighten the bolts to the specified torque. 19 Remove the Irolloy jack and lower the vehicle lo the ground. Rear mounting 20 Firmly apply the handbrake, then Jack up the front of the car and support It securely on axle stands (see Jacking and vehicle support). 21 Working beneath Ihe vehicle, unscrew Ihe bolts secunng the rear engine mounting to the underbody. 22 Temporarily support the weight of the engine/transmission using a trolley jack. 23 Unbolt the rear mounting assembly from Ihe transmission and withdraw from under the vehicle. 24 Unscrew the bolt and separate Ihe bracket from tlve mounting. 28 Fitting the new mounting Is a reversal of the removal procedure.
12 Sump -removal and refitting
12.2 Removing the flywheel housing cover plate 12.4 Removing the sump
Removal 1 Firmly apply the handbrake, then jack up the front of the car and support it securely on axle stands (see Jacking and vehicle support). Drain the engine oil as described in Chapter 1 A. 2 Unbolt and remove the cover plate from the lower pari of the llywheel housing (see illustration). 3 Refer to Chapter 4D and unbolt the exhaust Iront pipe from Ihe manifold. Undo Ihe support bracket fastenings and lower the front pipe clear of the sump. 4 Unscrew the sump securing screws and nuts and pull the sump downwards to remove it (see Illustration). The joint sealant will
Page 62 of 225

2A*10 SOHC (8-valve) petrol engine in-car repair procedures
Lubrication system Oil pump type By-rotor driven from front of crankshaft Outer rotor-io-houslng clearance 0.100 to 0.210 mm Axial clearance 0.025 to 0.070 mm
Torque wrench settings Nm itrf ft Camshaft driven gears 120 89 Camshaft sprocket 120 89 Crankshaft sprocket centre bolt: Stage
1
20 15 Stage 2 Angle-tighten a further 90® Cylinder head: Stage
1
30 22 Stage 2 Angle-tighten a further 90" Stage 3 Angle-tighten a further 90° Cylinder head extension to cylinder head 15 11 Engine mounting bolt: M10
x
1.25 59 44 M8 25 18 Engine mounting nut (MlOx 1.25) 60 44 Flywheel 44 32 Timing belt tensioner 25 18 Sump 10 7
1 General information
Using this Chapter Chapter 2 is divided into four Parts; A, B. C and O. Repair operations that can be carried out with the engine hi the vehicle are described in Part A. SOHC (8-valve) petrol engines. Part B, DOHC (16-valve) petrol engines and Pari C, dlesei engines. Part D covers the removal of the engine/transmission as a unit, and describes the engine dismantling and overhaul procedures. In Parts A, B and C, the assumption Is made that the engine is Installed In the vehicle, with all ancillaries connected. If the engine has been removed for overhaul, the preliminary dismantling information which precedes each operation may be ignored.
Engine description Throughout this Chapter, engines are identified by their capacities. A listing of all engines covered, together with their code letters, Is given in the Specifications. The engine covered in this Part of Chapter 2 is a water-cooled, double overhead camshaft, in-line four-cylinder unit, with cast iron cylinder block and aluminium-alloy cylinder head. The unit is mounted transversely at the front of the vehicle, with the transmission bolted to the left-hand side of the engine. The cylinder head houses the eight inlet and eight exhaust valves, which are closed by single coil springs, and which run in guides pressed Into the cylinder head. The two camshafts are housed in 8 cylinder head extension which is bolted to the top of the cylinder head. The exhaust camshaft is driven by a toothed timing belt and In turn drives the inlet camshaft via a pair of gears located at the left-hand end of the cylinder head extension.
The camshafts actuate the valves directly via self-adjusting hydraulic cam followers mounted in the cylinder head extension. The crankshaft is supported by five main bearings, and endfioat is controlled by a thrust bearing fitted to (he upper section of the centre main bearing. Engine coolanl is circulated by a pump, driven by the timing belt. For details of the cooling system, refer to Chapter 3. Lubricant is circulated under pressure by a pump, driven from the front of the crankshaft. Oil is drawn from Ihe sump through a strainer, and then forced through an externally-mounted, replaceable screw-on filter. From there, It is distributed to the cylinder head and cylinder head extension, where it lubricates the camshaft journals and cam followers, and also to the crankcase, where it lubricates the main bearings, connecting rod big and small-ends. gudgeon pins and cylinder bores. Oil Jets are fitted to the base of each cylinder bore - these spray oil onto the underside of the pistons, to improve cooling.
Repair operations possible with the engine in the car The following work can be carried out with the engine in the car: a) Auxiliary drivebett - removal and refitting (refer to Chapter 1A) b) Oil pump and pick-up tube assembly -removal, Inspection and refitting c) Timing belt and covers • removal and refitting d) Timing belt tensioner and sprockets -removal and refitting e) Cylinder head - removal and refitting' f) Cylinder hoad extension - removal and refitting g) Camshaft and cam followers - removal and refitting h) Camshaft oil seal - renewal i) Crankshaft oil seals • renewal
f) Flywheel - removal, inspection and
refitting
k) Engine mountings - Inspection and
renews'
f) Sump • removal and refitting 'Cylinder head dismantling procedures are detailed In Chapter 2D. Note 1: It is possible to remove the
pistons
and connecting rods (after removing (to cylinder head and sump) without removing
tt*»
engine. However, this Is not recommended. Work of this nature is more easily and thoroughly completed with the engine on fix bench, as described in Chapter 20. Note
2x
Many of the procedures in this Ctopfer entail the use of numerous special tools. Whet possible, suitable alternatives are descnbei with details of their fabrication. Before starring any operations on the engine, read through
tto
entire procedure first to familiarise yourself
wft
the work involved, tools to be obtained mi new parts that may be necessary.
2 Engine assembly/ valve timing holes -genera! information
and
usage
Note: Do not attempt to rotate the angint whilst the camshafts are locked In position,
il
the engine is to be left in this state foratofi$ period of time. It Is a good idea to plect suitable warning notices inside the vehicle, and in the engine compartment. This wfl reduce the possibility of the engine being accidentally cranked on the starter motor, which is likely to cause damage with the locking tools In place. 1 To accurately set the valve timing for ell operations requiring removal and refitting of
the
timing belt, liming holes are drilled in ihe camshafts and cylinder head extension. Ihe holes are used In conjunction with camshaft locking tools and crankshaft positioning
rods w
lock the camshafts when all the pistons me positioned at the mid-point of their stroke. Ths
Page 63 of 225

2B*3 DOHC (16-valve) petrol engine in-car repair procedures
2.2s Arrangement of Fiat special tools for setting the piston position and locking the camshafts
arrangement prevents the possibility of the vaivescontacting the pistons when refitting the cinder head or timing belt, and also ensures tet the correct valve timing can be obtained.
The design
of the engine is such that there are n> conventional timing marks on the crankshaft
er
camshaft sprockets to indicate the normal 70C position. Therefore, for any work on the lining belt, camshafls or cylinder head, the b&ng
and
positioning tools must be used.
2 The
special Fiat tools for setting the camshafts and pistons consist of two rods ttikh slide in sleeves that are screwed into
So
t and No 2 cylinder spark plug holes. The
rods are
pushed down to contact the pistons, ird the crankshaft is then turned until both tods protrude from their sleeves by the same enount. With the crankshaft correctly set,
ti»o
camshaft locking pins are used, one for tM inlet camshaft and one for the exhaust earretaft. The pins are screwed into holes on *ach »de of the cylinder head extension so M they engage with slots machined In (he
2.2b Fiat special tool for setting piston position...
camshafts. The arrangement of the Rat special tools are shown (see illustrations). The tool numbers are as follows: Camshaft locking toots Toot No 1860985000 Piston positioning tool Toot No 1860992000
2.2c ... and locking the camshafts
3 Although the special Fiat tools are relatively inexpensive and should be readily available from Flat dealers, it is possible to fabricate suitable alternatives, with the help of a local machine shop, as described below. Once the tools have been made up, their usage Is described In the relevant Sections of this Chapter where the tools are required. Camshaft locking tool fabrication 4 Remove the air cleaner, inlet air duct and resonator as descnbed in Chapter 4B. 5 Unscrew the sealing plug from the front face of the cylinder head extension. 6 Using the sealing plug as a pattern, obtain a length of threaded dowel rod or two suitable bolts to screw into the sealing plug hole. With the help of a machine shop or engineering works, make up the camshaft locking toots by having the dowel rod or bolts machined to the dimensions shown (see illustrations). Note that two will be needed, one for each camshaft.
Suitabt* roll pin (or titling /
ramoviitg
tool
-J 10 h -4 h
AT —
T
—
2,6a To make an alternative camshaft locking tool... 2.6b ... have suitable dowel rods or bolts machined to the dimensions shown
Page 65 of 225

2B*5 DOHC (16-valve) petrol engine in-car repair procedures
4.11a Release the crankshaft TDC sensor wiring from the clip on the upper timing cover... throttle potentiometer and the Idle control stepper motor. Disconnect the coolant temperature sensor wiring connector located
in
the inlet manifold below the throttle body,
end
disconnect the brake servo vacuum hose. 15 Disconnect the wiring connectors for the fuel injector harness and the intake air temperature/pressure sensor, then fcconnect the fuel pressure regulator vacuum hose and the EVAP purge valve hose. 18 Undo the two bolts securing the plastic mlet manifold upper section to the lower section. Release the spark plug HT lead from the location groove in the manifold upper wctton, then lift the upper section, complete
»ith
throttle body, off the engine. Recover the 0-rngs from the manifold ports. 17 Unscrew the two bolts securing the fuel
4£1a Screw the spark plug bodies of the homo-made piston positioning tools into each spark plug hole ...
4.21b ... place a suitable washer or similar into the recess to keep the dowel rod vertical...
4.11b ... then slide the wiring plug and socket from the timing cover slot
rail assembly to the inlet manifold lower section, then carefully pull the Injectors from the manifold. Lift the fuel rail and Injector assembly, with fuel hoses still connected, and position it to one side. 16 Undo the bolts securing the engine management ECU mounting brackets to the body and move the ECU to one side without disconnecting the wiring connector. 19 Remove the spark plugs as described in Chapter 1A. 20 Unscrew the two sealing plugs from the front and rear of the cylinder head extension to enable the camshaft locking tools to be inserted. 21 Screw the spark plug bodies of the home-made piston positioning tools into each spark plug hole and insert the dowel rods into each body. To keep the dowel rods vertical, locate a suitable washer or similar over Ihe rod and into the recess at the top of the spark plug hole. In the photos shown here, an old valve stem oil seal housing was used but anything similar will suffice (see illustrations). 22 Using a socket on the crankshaft sprocket centre bolt, turn the crankshaft in the normal direction of rotation until all four dowel rods are protruding from the top of the cylinder head extension by the same amount. As the engine is turned, two of the rods will move up and two will move down until the position is reached where they are all at the same hoight. The best way to check this is to place a straight edge along the top of the rods and turn the crankshafl very slowly until the
4.21c ... then insert the dowel rods
4.12b ... and lower timing covers
straight edge contacts all four rods (see illustration). 23 When all four rods are at the same height, all the pistons will be at the mid-point of their stroke. Using a screwdriver or similar inserted into the front timing hole in the cylinder head extension, check that the timing slot in the exhaust camshaft is approximately aligned with the liming hole. If the camshaft slot cannot be felt, turn the crankshaft through one complete revolution and realign the dowel rods using the straight edge. Check again for the camshaft slot. Note that although the pistons can be at the mid-point of their stroke twice for each cycle of the engine, the camshaft slots will only be positioned correctly once per cycle. 24 With the pistons correctly set, it should now be possible to screw in the camshaft
4.22 Place a straight edge along the top of the rods and turn the crankshaft until the straight edge contacts ail four rods