Reference FIAT PUNTO 1998 176 / 1.G User Guide

ib-io Every 10 000 miles - diesel models
7 With the car standing on Its wheels, have an assistant turn the steering wheel back and forth about an eighth of a turn each way. There should be very hide. If any, lost movement between the steering wheel and roadwheels. If this is not the case, closely observe the joints and mountings previously described, but in addition, check the steering column universal joints for wear, and the rack-and-plnion steering gear itself.
Suspension strut/ shock absorber check 8 Check for any signs of fluid leakage around the suspension strut/shock absorber body, or from the rubber gaiter around the piston rod, Should any fluid be noticed, the suspension strut/shock absorber is defective Internally, and should be renewed. Note: Suspension struts/shock absorbers should always be renewed in pairs on the same axle.
9 The efficiency of the suspension strut/shock] absorber may be checked by bouncing 0*1 vehicle at each comer. Generally speaking. th»| body will return to its normal position and 8top| after being depressed. If It rises and returns cn| a rebound, the suspension strut/shocH absorber is probably suspect. Examine also* the suspension strut/shock absorber uppeij and lower mountings for any signs of wear.
Every 20 000 miles (30 000 km) or 2 years
18 Auxiliary drivebeltfs) % check and renewal
Note: Fiat specify the use of a spec/a/ toot to correctly set the drivebelt fens/on. if access to this equipment cannot be obtained, an approximate setting can be achieved using the method described beiow. If the method described Is used, the tension should be checked using the spec/a/ too! at the earliest possible opportunity. 1 Depending on equipment fitted, one, two or three auxiliary drivebeits may be fitted. The alternator, power steering pump and air conditioning compressor, as applicable, are each driven by an individual drivebelt. Checking 2 Disconnect the battery negative terminal (refer to Disconnecting the battery In the Reference Section of this manual). 3 Firmly apply the handbrake, then Jack up the Iront of the car and support it securely on exie stands (see Jacking and vehicle support). 4 Remove the right-hand wheel. 5 Remove the Inner cover(s) from under the right-hand wheelarch for access to the right-hand side of the engine. 6 Using a socket on the crankshaft sprocket bolt, rotate the crankshaft so that the full length of the auxiliary drivebelt(s) can be examined. Look for cracks, splitting and fraying on the surface of the belt: check also for signs of glazing (shiny patches) and
16.10a Loosening the alternator drivebelt adjustment bolt
separation of the belt plies. If damage or wear Is visible, the bell should be renewed, 7 If the condition of the belt Is satisfactory, check tho drivebelt tension as described below.
Renewal
Alternator drivebelt 8 On models with air conditioning, remove the compressor drivebelt as described below, 9 Unclip and remove the upper timing belt cover, then unbolt end remove the lower timing belt cover. 10 Loosen the pivot bolt and adjustment lockbolt then unscrew the adjustment bolt to move the alternator towards the engine so that the drivebelt may be slipped off the alternator, crankshaft, and, on models with air con-ditioning, the Idler pulley (see Illustrations), 11 When renewing a drivebelt. ensure that the correct type is used. Fit the belt around the pulleys then tighten the adjustment bolt to take up any slsck In the belt. Adjust the tension correctly as described below. Power steering pump drivebelt
12 Remove the alternator drivebelt as described previously. 13 Slacken the bolts securing the power steering pump to the mounting bracket. 14 Slacken the adjusting bolt locknut and turn the adjusting bolt until ail the tension Is removed from the dnvebelt. 15 Undo the bolts and remove the pulley guard from the power steering pump then slip the drivebelt off the pulleys,
16.10b Removing the drivebelt from the alternator pulley
18 Ensuring that the correct type of dnveberti^ used, fit the belt around the pulleys and turn
the
adjusting bolt to just take up the slack in thi j belt. Adjust the tension correctly as described! below. Air conditioning compressor drivebelt 17 Slacken the bolts securing the adjustment j pulley bracket to the engine. 18 Slacken the adjusting bolt locknut and] turn the adjusting bolt until ell the tension is | removed from the drivebelt. then slip the be& | off the pulleys. 19 Ensuring that the correct type of drivebeX; is used, fit ihe belt around the pulleys and turn | the adjusting bolt to just take up the slack
m
] the belt. Adjust the tension correctly as described below.
Tensioning 20 Correct tensioning of the belt will ensure that it has a long life. A belt which is too slack will slip and perhaps squeal. Beware, however, of overiightenlng. as this can cause wear in the alternator, power steering pump or air conditioning compressor bearings. Note: Flat recommend use of their spec's/ tensioning tool however the following procedure will set the tension correctly. 21 The belt(s) should be tensioned so that, under firm thumb pressure, there is approximately 5.0 mm of free movement at the mid-point between the pulleys. To adjust, tighten or loosen the relevant adjustment bolt until the tension is correct. Fully tighten the pivot and adjustment lockbotts. Repeat this procedure for any remaining drivebeits removed for access. 22 Refit the lower timing belt cover end tighten the mounting bolts. 23 Refit the upper timing belt cover and secure with the clips. 24 Refit the inner cover and wheel, lower the vehicle to the ground, then reconnect the battery negative terminal.
17 Clutch adjustment check
Refer lo Chapter 6, Section 2.

ib.14 Every 2 years - diesel models
Radiator flushing 7 To flush the radiator disconnect the top and bottom hoses and any other relevant hoses from the radiator, with reference to Chapter 3. 8 Insert a garden hose into the radiator top inlet. Direct a flow of dean water through the radiator, and continue Hushing until clean water emerges from the radiator bottom outlet. 9 II after a reasonable period, the water still does not run clear, the radiator can be flushed with a good proprietary cooling system cleaning agent. It is important that their manufacturer's instructions are followed carefully. If Ihe contamination is particularly bad, insert the hose in the radiator bottom outlet, and reverse-flush the radiator.
Engine flushing 10 To flush tho engine, remove the thermostat as described in Chapter 3. 11 With the bottom hose disconnected, direct a clean flow of water through the engine, and continue Hushing until clean water emerges from the radiator bottom hose. 12 On completion of flushing, refit the thermostat and reconnect the hose with reference to Chapter 3.
Cooling system filling 13 Before attempting to fill the cooling system, make sure that all hoses and clips are in good condition, and that the clips are tight. Note that an antifreeze mixture must be used all year round, to prevent corrosion of the engine components (see following sub* Section). 14 Remove the expansion tank filler cap. and fill the system by slowly pouring the coolant Into Ihe expansion tank to prevent airlocks from forming. Ensure that all bleed plugs/screws are open. 15 If the coolant is being renewed, begin by pouring in a couple of litres of water, followed by the correct quantity of antifreeze, then top* up with more water. 18 Once ihe level in the expansion tank starts to rise, squeeze the radiator top and bottom hoses to help expel any trapped air in
the system. Once all the air is expelled, top-up the coolant level to the MAX mark and refit the expansion tank cap. Close all bleed plugs. 17 Start Ihe engine and run il until it reaches normal operating temperature, then stop the engine and allow It to cool. 18 Check for leaks, particularly around disturbed components. Check the coolant level In the expansion tank, and top-up if necessary. Note that the system must be cold before an accurate level Is indicated In the expansion tank. If the expansion tank cap Is removed while the engine is still warm, cover the cap with a thick cloth, and unscrew the cap slowly to gradually relieve the system pressure (a hissing sound will normally be heard). Wait until any pressure remaining in the system Is released, then continue to turn the cap untH it can be removed.
Antifreeze mixture 19 The antifreeze should always be renewed at the specified intervals. This is necessary not only to maintain the antifreeze properties, but also to prevent corrosion which would otherwise occur as the corrosion Inhibitors become progressively less effective. 20 Always use an ethylene-glycol based antifreeze which is suitable for use in mixed-metal cooling systems. The quantity of antifreeze and levels of protection are indicated in the Specifications. 21 Before adding antifreeze, the cooling system should be complelely drained, preferably flushed, and all hoses checked for condition and security. 22 After filling with antifreeze, a label should be attached to the expansion tank, stating the type and concentration of antifreeze used, and the dale installed. Any subsequent topping-up should bs made with the same type and concentration of antifreeze. 23 Do not use engine antifreeze In the windscreen/tailgate washer system, as it will cause damage to the vehicle paintwork. A screenwash additive should be added to the washer system in the quantities stated on the bottle.
28 Brake fluid renewal

A


Warning: Brake hydraulic fluid can harm your eyas and damage painted surfaces, so use extreme caution when handling and pouring It. Do not use fluid that has been standing open for some time, as It absorbs moisture from the air. Excess moisture can causa a dangerous loss of braking effectiveness. 1 The procedure is similar to that for the bleeding of the hydraulic system as described In Chapter 9. except that the brake fluid reservoir should be emptied by siphoning, using a clean poultry baster or similar before starting, and allowance should be made for the old fluid to be expelled when bleeding a section of the circuit. 2 Working as described in Chapter 9, open Ihe first bleed screw in the sequence, and pump the brake pedal gently until nearly all the old fluid has been emptied from the master cylinder reservoir.
ffffTOgf Old hydraulic fluid Is
lifcjllitt*
Invariably much darker In [HINT] colour than the new, making /{easy to distinguish the two.
3 Top-up to the MAX level with new fluid, and continue pumping until only the new fluid remains in the reservoir, and new fluid can be seen emerging from (he bleed screw. Tighten the screw, and top the reservoir level up to Ihe MAX level line. 4 Work through all the remaining bleed screws In the sequence until new fluid can be seen al all of them. Be careful to keep the master cylinder reservoir topped-up 10 above the MIN level al all limes, or air may enter the system and greatly increase the length of the task. 5 When the operation is complete, check thai all bleed screws are securely tightened, and that their dust caps are refitted. Wash off ail traces of split fluid, and recheck the master cylinder reservoir fluid level. 6 Check the operation of the brakes before taking the car on the road,

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.

2A*10 SOHC (8-valve) petrol engine in-car repair procedures
I To make o camshaft sprocket holding ; tool, obtain two lengths of steel strip I about 6 mm thick by 30 mm wide or ; similar, one €00 mm long, the other 200 mm long (all dimensions approximate). Bolt the two strips together to form a forked end, leaving the bolt slack so that the shorter strip can pivot freely. At the end of each 'prong' of the fork, secure a bolt with a nut and a locknut, to act as the fulcrums; these will engage with the cut-outs In the sprocket, and should protrude by about 30 mm
11 Check and adjust the tension of the timing tel with reference to Section 4. 12 Relit Ihe timing belt cover and tighten the bolts. 13 Relit the crankshaft pulley. 14 Refit and tension the auxiliary drivebelt(s)
as
described in Chapter 1. 15 Refil the air cleaner and air ducting as described in Chapter 4A or 48. 16 Refil the roadwheel and lower the vehicle
to the
ground.

Camshaft
sprocket
Removal 17 Remove the timing bell as described in Section 4. 16 The camshaft sprocket must now be held stationary while the retaining bolt is loosened. To
cto this,
make up a tool as follows and engage it
with the
holes
in
the sprocket (see Tool Tip). 19 Alternatively pass a rod through one of the holes in the camshaft sprocket to prevent it rotating. Position a pad of rag or a piece of
integral key
securing bolt and washer...
wood under the rod to avoid damaging the cylinder head. 20 Unscrew the bolt and slide the sprocket from the end of tho camshaft. Note the integral location key on the inner face of the sprocket (see illustrations). Inspection 21 With the sprocket removed, examine the camshaft oil seal for signs of leaking. If necessary, refer to Section 7 and renew it. 22 Check the sprocket teeth for damage. 23 Wipe clean the sprocket and camshaft mating surfaces. Refitting 24 Locate the sprocket on the end of the camshaft, then refit the bolt and washer and tighten to the specified torque while holding the camshaft stationary using the method described previously. 25 Refit the timing belt as described in Section 4.
Crankshaft sprocket
Removal 26 Remove the timing belt as described in Section 4. 27 Working beneath the engine, unbolt and remove the flywheel lower cover, then hold the flywheel stationary preferably using a toot which engages the flywheel starter ring gear (see Section 10). Alternatively have an assistant engage a wide-bladed screwdriver with the stader ring gear. 26 Unscrew the crankshaft sprocket retaining bolt and slide the sprocket off the end of the
^P
5.32 Tighten the crankshaft sprocket bolt to the specified torque
end of the camshaft Integral location key (arrowed)
crankshaft. The sprocket may have an integral location key on its inner face (see illustration), or a separate key which locates in a groove in the crankshaft nose may be fitted. Inspection 29 With the sprocket removed, examine the crankshaft oil seal for signs of leaking. If necessary, refer to Section 8 and renew it. 30 Check the sprocket teeth for damage. 31 Wipe clean the sprocket and crankshaft mating surfaces. Refitting 32 Slide the sprocket onto the crankshaft making sure it engages the integral key or separate key, then refit the bolt and washer and tighten the bolt to the specified torque while holding the crankshaft stationary using the method described in paragraph 27 (see illustration). 33 Refit the timing belt as described in Section 4.
6 Camshaft cover -removal and refitting
Removal 1 Remove the air cleaner assembly and inlet duct as described in Chapter 4A or 4B. 2 Progressively unscrew the mounting bolts from the top of the camshaft cover and lift off the cover • note the location of any supports on the bolts (see illustration). If it sticks, do
6.2 Removing the camshaft cover

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.

2B*4 DOHC (16-valve) petrol engine in-car repair procedures
4.8 Undo three bolts and romove tho crankshaft pulley from the sprocket
Crankshaft setting toot fabrication 7 To make Ihe crankshafl setting tools, four old spark plugs will be required, together with four lengths of dowel rod. The length of each dowel rod is not critical, bul It must be long enough to protrude about 100 mm above the top of the cylinder head extension when resting on top of a piston located half way down its bore. What is critical, however, is that all four do wo I rods must be exactly the same length. 8 Break off the ceramic upper section of each plug and remove the centre electrode and earth tip. The easiest way to do this is to mount each spark plug in a vice (attar removing the ceramic uppor plug section) and drill a hole down through ihe centre of the plug. The diameter of Ihe drill bit should be the same as Ihe diameter of Ihe dowol rod to be used. When finished you should have four spark plug bodies and four equal length dowel rods which will slide through the centre of the spark plugs.
3 Cylinder compression test
1 When engine performance is down, or it misfiring occurs which cannot be attnbuted to the Ignition or fuel systems, a compression test can provide diagnostic clues as to the engine's condition. If the lest is performed regularly, it can give warning of trouble bofore any other symptoms become apparent.
4.10 Undo the upper timing cover upper retaining bolt, and the rear retaining boll
4.9 Undo the retaining bolt in the centre of the lower timing cover
2 The engine must be fully warmed-up to normal operxrtrfjg temperature, the battery must be fully charged, and all the spark plugs muse be removed (Chapter 1A>. The aid of an assistant wilt also be required. 3 Disable the ignition system by discon-necting the LT wiring plugs to the Ignition coils. 4 Fit a compression tester to the No t cylinder 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 h.ghest reading obtained 6 Repeat the test on the remaining cylinders, recording Ihe pressure in each. 7 All cylinders should produce very similar pressures; any excessive difference indicates Ihe existence of a fault. Note that the compression should build up quickly in a healthy engine; low compression on (he 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 tho cause). 6 If the pressure in any cylinder is very low, carry out the following test to isolate the cause. Introduce a teaspoonful of dean oil into that cylinder through its spark plug hole and repeal the lest. 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 blown 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 Ihem; the presence of coolant in the engine oil will confirm this. 11 If one cylinder is about 20 percent lower than the others and the 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 §
General information 1 The luncUon of the timing belt Is to drive the camshafts and coolant pump. Should the bell slip or creak in service, the valve timing will be disturbed and piston-to-valve contact wiu occur, resulting in serious engine damage. 2 The timing belt should be renewed at 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 coolam pump at the same time (oheck for signs of coolant leakage). This may avoid the need to remove the timing belt again at a later stage, should the coolant pump fail. 4 Before carrying out this procedure, it will be necessary to obtain or fabricate suitable camshaft locking tools and piston positioning tools as described in Section 2. The procedures contained In this Section depict the use of the home-made alternative tools described in Section 2. which were fabricated In the Haynes workshop. If the manufacturers tools are being used instead, the procedures are virtually identical. Oo not attempt to remove the timing bell unless the special totfs or their alternatives are available.
Removal 5 Disconnect the battery negative terminal (refer to Disconnecting the battery in the Reference Section of Ihis manual). 6 Remove the auxiliary drivebelt(s) as described In Chapter 1A. 7 Remove the air cleaner, Inlet air duct and resonator as desenbed In Chapter 4B. 8 Undo the three bolts and remove the crankshaft pulley from the sprocket (see illustration). 9 Undo the retaining bolt In the centre of the lower liming cover (see illustration). 10 Undo tho uppor timing cover upper retaining bolt, and the rear retaining bolt located above the alternator (see illustration). 11 Release the crankshaft TDC sensor wiring from the clip on the upper timing cover, then withdraw the cover slightly and slide Ihe wiring plug and socket from the liming cover slot (see illustrations). 12 Release the TDC sensor wiring from the periphery ol the upper and fower timing covers and remove both covers (see Illustrations). 13 Free the accelerator inner cable from the throttle cam, remove the outer cable spring dip, then pull the outer cable out from its mounting bracket rubber grommet. 14 From the side of the throttle body, disconnect the wiring connectors from the

2B*7 DOHC (16-valve) petrol engine in-car repair procedures
35 Slacken the tensioner pulley retaining nut and reposition the tensioner to align the
mobile
indicator with the fixed reference mark
on the
pulley face (see illustration). Hold the
pdley in
this position and tighten the retaining
nut to the
specified torque. 36 Turn the crankshaft through a further two complete turns In the normal direction of rotation. Check that the timing is correct by alining Ihe piston positioning tools and
camshaft
locking tools as described previously. 37 When all is correct, remove the setting rri
locking
tools and refit the sealing plugs to 1ft© cylinder head extension, using new 0-
nr^s if
necessary. Tighten the plugs securely. 38 Refit the spark plugs as described in Chapter 1A. 39 Refit Ihe ECU and secure with Ihe mooning bolts. 40
Renew the
injector O-ring seals, smear them Kith
8 little
Vaseline then locate the injectors and tef rail onto the inlet manifold lower section.
Saute Ihe fuel rail
with the two retaining bolts. 41 Relit the inlet manifold upper section using new sealing O-rlngs If necessary and
sectre
with the two bolts. 42 Reconnect the wiring connectors for the tot injector harness and the intake air temp-erature/pressure sensor, then connect the fuel pressure regulator vacuum hose and tha
EVAP
purge valve hose. 43 Reconnect the wiring connectors for the ihrottls potentiometer, idle control stepper motor and coolant temperature sensor. Reconnect the brake servo vacuum hose. 44 Refit and adjust the accelerator cable as described in Chapter 4B. 46 Refit the upper and lower timing belt
covers
together with the TDC sensor wiring. 46 Refit the crankshaft pulley and tighten the
three
retaining bolts securely. 47 Refit the air cleaner. Inlet air duct and resonator as described in Chapter 4B. 48
Refit
tha auxiliary drivebelt(s) as described i/t Chapter 1A, then reconnect the battery
S Timing belt tensioner
and
sprockets -
removal
and refitting

Timing
belt tensioner
Removal I
Remove
the timing belt as described in
Section
4. 1 Completely unscrew the tensioner nut and Wiethe tensioner off the mounting stud-Inspection
3 Wipe
the tensioner clean but do not use Kfrents that may contaminate the bearings.
Spin
the tensioner pulley on its hub by hand.
Sfcfl
movement or excessive freeplay is an rcfceticn of severe wear: the tensioner is not 3 serviceable component, and should be nnewsd.
4.33 Holding the camshaft sprocket with the tool described previously while tightening the sprocket bolt Refitting 4 Slide the tensioner pulley over the mounting stud and fit the securing nut. 5 Refit the timing belt as described in Section 4. Camshaft sprocket Removal 6 Remove the timing belt as described in Section 4. 7 Unscrew the bolt and slide the sprocket from the end of the camshaft. Inspection 8 With the sprocket removed, examine the camshaft oil seal for signs of leaking. If necessary, refer to Section 6 and renew it. 9 Check the sprocket teeth for damage. 10 Wipe clean the sprocket and camshaft mating surfaces. Refitting 11 Locate the sprocket on the end of the camshaft, then refit the retaining boll finger tight only at this stage. 12 Refit the timing belt as described in Section 4.
Crankshaft sprocket Removal 13 Remove the timing bell as described In Section 4. 14 Working beneath the engine, unbolt and remove the flywheel lower cover, then hold the flywheel stationary preferably using a tool which engages the flywheel starter ring
<

Alternatively have an assistant engage a wide-bladed screwdriver with the starter ring gear. 15 Unscrew the crankshaft sprocket retaining bolt and slide the sprocket off the end of the crankshaft. The sprocket may have an integral location key on its inner face, or a separate key which locates In a groove in the crankshaft nose may be fitted. Inspection 16 With the sprocket removed, examine the crankshaft oil seal for signs of leaking. If necessary, refer to Section 7 and renew it. 17 Check the sprocket teeth for damage. 18 Wipe clean the sprocket and crankshaft mating surfaces. Refitting 19 Slide the sprocket onto the crankshaft making sure
11
engages the integral key or separate key, then refit the bolt and washer and tighten the bolt to the specified torque while holding the crankshaft stationary using the method described in paragraph 14. 20 Refit the timing belt as described in Section 4.
6 Camshaft
oil
seal -renewal
1 Remove the timing belt and camshaft sprocket as described in Sections 4 and 5. 2 Punch or drill a small hole in the oil seal. Screw a self-tapping screw into the hole, and pull on the screws with pliers to extract the seal. 3 Clean the seal housing, and polish off any burrs or raised edges, which may have caused the seal to fall in the first place. 4 Lubricate the lips of the new seal with clean engine oil, and drive it into position until It seats on its locating shoulder. Use a suitable tubular drift, such as a socket, which bears only on the hard outer edge of the seal. Take care nof to damage the seal lips during fitting. Note that the Seal lips should face inwards. 5 Refit the camshaft sprocket and timing belt as described in Sections 5 and 4.
7 Crankshaft oil seats -renewal I
4.35 Position the tensioner so that the mobile Indicator (1) is aligned with the fixed reference mark (2)
Front (right-hand side) oil seal 1 The front oil seal is located in the 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 the 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.

2B*8 DOHC (16-valve) petrol engine in-car repair procedures
8.3a Disconnect the LT wiring plugs from the two Ignition coils ... 4 Dip the new oil seal in oil then offer it up to the oil pump casing making sure that the sealing Hps are facing inwards. 5 Using a suitable tubular drift, drive the oil seal squarely into the casing. Remove the adhesive tape, 8 Reftl the crankshaft sprocket and timing belt wrth reference to Sections 5 and
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 20 for details of removing ihe housing. 7 Remove the flywheel as described In Section 11. 8 Using a suitable hooked Instrument, remove the oil seal from the rear oil seal
L •
~ 1 8.8a Lift the cylinder head extension slightly and insert the tools {shown with cylinder head removed for clarity)...
8.3b ... then unscrew the mounting bolts end romove the ignition colls housing taking care not to damage the surface of the crankshaft. 9 Clean the seating In the housing and the surface of Ihe crankshaft. Check the crankshaft for burrs which may damage the sealing lip ol Ihe new seal, and If necessary use a Tine file to remove them. 10 Dip the new seal In clean engine oil and carefully locate it over Ihe 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 flywheel with reference to Section 11,
8 Cylinder head extension -removal and refitting ^
Removal 1 Remove the timing bolt as described in Soction A. 2 Identify the two HT leads for position then disconnect them from the coil HT terminals. 3 Disconnect the LT wiring plugs from the two ignition coils, then unscrew the mounting bolts and remove the ignition coils from the and of the cylinder head extension {see illustrations). A Undo the bolt and remove the resonator support bracket from Ihe top of the cylinder head extension,
8.8b ... thon remove the cylinder head extension
8.G Unscrew tho protective caps covering the cylinder head extension retaining bolts
5 Unscrew the protective caps covering the cylinder head extension retaining bolts (see Illustration). 6 To retain the cam followers in place as the cylinder head extension Is removed. Flat special tool No 1860988000 will bo required. This tool consists of two strips ol suitably slotted thin metal angle which sDp between the cylinder head extension and cylinder head mating faces as the extension Is lifted off. The tool holds the cam followers in place in the extension allowing the assembly to be withdrawn without fouling the Inlet and exhausl valves, The tools are refetJvety inexpensive and readily available from Fiat dealers. Suitable alternatives can be fabneated, If desired, usrnj thin metal angle strip cut to the dimensions shown (see Tool tip). 7 Progressively slacken and remove the boll$ securing the cylinder head extension to the cylinder head. 8 Lilt tho cylinder head extension up very slightly, keeping it square to the cylindei head. Slip the toots in place to hold the cam followers, then lift the extension off the cylinder head (see illustrations). Recover the gasket between the two assemblies. 9 Dismantling and Inspection procedures lor the cylinder head extension and camshafts are given in Section 9. Refitting 10 Ensure thai Ihe mating faces of the cylinder head and extension aro thorough^ cleaned, with all traces of old gasket removed, then locate a new gasket on Ihe cylinder head (see Illustration).
8.10 Locate a new gasket on the cylinder head
To make a cam follower retaining tool, obtain two lengths of 1hln metal angle and cut both to the dimensions (In mm) shown

2C*2 Diesel engine in-car repair procedures
1 General information
Using this Chapter Chapter 2 is divided Into four Parts; A. 8, C and 0. Repair operations that cart be carried out with the engine in the vehicle are described In Part A, SOHC (B-valve) petrol engines. Part B, DOHC (16-valve) petrol engines and Part C. diesel engines, Part D covers the removal of the engine/transmission as a unit, and describes the engine dismantling and overhaul procedures. In Parts A. 8 and C. the assumption Is made that the engine is installed in Ihe vehicle, with all anciliaries connected If the engine has been removed for overhaul, the preliminary dismantling information which precedes each operation may be ignored.
Engine description Both normally aspirated (non-turbo) and turbocharged diesel engines are fitted to the Punto range. The engines together with their codes are given in the Specifications at the start of lhis Chapter. The engines are water-cooled, single-overhead camshaft. In-line lour cylinder units with cast-iron cylinder blocks and aluminium-alloy cylinder heads. The engine is mounted transversely at the front of 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. It also houses the inlet and exhaust valves which are closed by single coll valve springs and run in valve guides pressed into the cylinder head. The valves are operated by cam followers fitted over each valve, and the clearances are adjusted by shims positioned between the followers and the camshaft lobes. The camshaft is supported by four bearings • the end bearings are machined in the cylinder head and the remaining bearings have caps bolted to the cylinder head. The cylinder head contains integral oiiways which supply and lubricate the camshaft and followers and it also Incorporates renewable swirl chambers. The crankshaft Is supported by five main bearings, and endfloat Is controlled by a thrust bearing fitted on the rear main bearing. All diesel engines are fitted with a brake servo vacuum pump dnven from the left-hBnd end of the camshaft. Engine coolant is circulated by a pump, driven by the auxiliary drivebeit. 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 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 il lubncates the camshaft journals and 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, lo Improve cooling. An oil cooler is also fitted to reduce the temp-erature of oil before it re-enters the engine.
Repair operations possible with the engine in the car The following work can be carried out with the engine in the can a) Compression pressure - testing b) Auxiliary drivebeit - removal and refitting (refer to Chapter rej c) Valve clearances • checking and adjustment (refer to Chapter 1B) d) Camshaft cover - removal and refitting e) Tim/ng belt and covers • removal and refitting 0 Timing belt tensioner and sprockets -removal and refitting g) Cylinder head - removal and refitting' h) Camshaft and cam followers - removal end refitting' I) Camshaft oil seal - renewal j) Crankshaft oil seals - renewal k) Flywheel • removal, inspection and refitting I) Engine mountings - inspection and renewal m)Sump • removal and refitting n) Oil pump and pick-up tube assembly -removal, inspection and refitting 'Cylinder head dismantling procedures are detalfed In Chapter 2D, with details of camshaft and cam follower removal. Note: It ts possible to remove the pistons and connecting rods (after removing the cylinder nead 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 tho bench as described in Chapter 2D.
2 Location of
TDC
on ^ No
1
cylinder ||
General information 1 The camshaft and fuel Injection pump are driven by the crankshaft, by means of sprockets and a timing belt. All three sprockets rotate in phase with each other and this provides the correct valve and injection pump timing as the engine rotates. When the timing bell is removed during servicing or repair, it is possible for the camshaft, injection pump and crankshaft to rotate independently of each other and the correct timing Is then lost.
2 It Location of TDC on cylinder No
1
6 Remove the air inlet ducting as described ft Chapter 4C, Section 2. 7 Remove the heater glow plugs with reference to Chapter 5C. Due to the high compression ratio of diesel engines this Is necessary to allow the engine to be turned by hand. 8 Unscrew the mounting bolts and move the coolant expansion tank to one side for access to the timing covers. Release the hose from the clips on Ihe camshaft cover. 9 Release the toggle clips and remove the upper timing cover (see illustration),
2.9 Removing the upper timing cover