1994 FIAT PUNTO check engine light

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.

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

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

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*6 DOHC (16-valve) petrol engine in-car repair procedures
4.24a Scrow in the camshaft locking tools into the timing holes in the cylinder head extension
locking tools Into the timing holes in the cylinder head extension. To provide the necessary degree of timing accuracy, the machined end of the locking tools are a very close fit in the slots machined in the camshafts. To allow the tools to be screwed
4.26 Slip the timing belt off the sprockets
To make a camshaft sprocket holding tool, obtain two lengths of steel strip about 6 mm thick by 30 mm wide or simitar, one 600 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 sfrfp 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 profrude by about 30 mm
4.24b The tools engage in tho camshaft slots when fitted (shown removed for clarity)
fully into engagement, it may be necessary to move the crankshaft In one direction or another very slightiy until the tools are felt to engage fully (see illustrations). 25 Release tho nut on the timing belt tensioner to release the tension on the belt (see illustration) 26 II the timing belt is to be re-used, use white paml or chalk to mark the direction of rotation on the belt (if markings do not already exist), then slip the belt off the sprockets (see illustration). Note that the crankshaft must not be rotated whilst the belt is removed. 27 Check the timing belt carefully for any signs of uneven wear, splitting, or oil contamination. Pay particular attention to the roots ol the teeth. Renew it If there is the slightest doubt about its condition. If the engine is undergoing an overhaul, renew the belt as a matter of course, regardless of its apparent condition. The cost ol a new bett is nothing compared with the cosi of repairs, should the belt break in service. If signs of oil contamination are found, trace the source of the oil leak 8nd rectify it. Wash down the engme timing belt area and all related components, to remove all traces of oil,
Refitting 28 Before refilling, thoroughly clean the liming bell sprockets. Check that Ihe tensioner pulley rotates freely, without any sign of roughness. If necessary, renew Ihe tensioner pulley as described in Section 5,
4.31 Fit the new belt around the sprockots observing the direction markings
4.25 Release the nut on the timing belt tensioner (arrowed)
29 The camshaft sprocket retaining bolt mutt; now be slackened to allow the sprocket Ic move as the timing bell Is refitted una tensioned. To hold the sprocket stationary^ while the retaining bolt is loosened, make upi. tool os follows and engage
>t
with the holes ^ i the sprocket (see Tool Tip). With the sprocket. held, slacken the retaining bolt. 30 Check that the pi6tons are still correct positioned at ihe mid-point of their stroke are that the camshafts are locked with the lockup: tools. 31 Ensuring that the direction markings on the timing belt point in the normal direction
cf
engine rotation, engage the Umlng belt vr* Ihe crankshaft sprocket first, then placed around the coolant pump sprocket and tte: camshaft sprocket (see Illustration). Rnaii>; slip the belt around the tensioner pulley. 32 Insert the jaws of a pair of right-angleo clrclip pliers (or similar) into Ihe two holes on; Ihe front face of the tensioner pulley (sec Illustration). Rotate the pulley to tension Ihj; belt until the belt Is quite taut. Maintain thr effort applied to the tensioner pulley. JM* tighten the pulley retaining nut. 33 Tighten the camshaft sprocket retains; bolt to the specified torque while holding th?; camshaft stationary using the method described previously (see Illustration). 34 Remove the piston positioning tools arc camshaft locking tools and turn In*; crankshaft through two complete turns In the normal direction of rotation,
4.32 Using right-angled clrclip pliers, turn the tensioner pulley to fully tension the bell

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

DOHC (16-valve) petrol engine in-car repair procedures 2B*11
camshaft cover plate... 25 Locate the cam follower retaining tools in position and refit the cylinder head extension
as
described In Section 8.

10
Cylinder head - &
removal and
refitting S
Removal Note; The cylinder head bolts are of special
sekned
design and a Fiat tool should be
obtained
to unscrew them. A Ton key will not
JSt however
in practise It was found that a dose-httlng Alien key could be used as an itemative. 1 Drain the cooling system as described in Chapter 1A. 2 Remove the cylinder head extension as oescAbed
m
Section 8. 3 Disconnect the radiator hose from the thermostat housing on the left-hand end of
Ihe
cylinder head. 4 Disconnect the heater hose from the outlet
at the
rear of the cylinder head. 5 Disconnect the coolant temperature sensor md temperature gauge sensor wiring plugs
torn
the left-hand end of the cylinder head. 9 Undo the engine oil dipstick tube bracket retaining bolt and the two bolts securing the wing harness support clips to the inlet marriold lower section. 7 Undo Ihe retaining nuts and separate the ixhaust system front pipe from the exhaust manifold flange.
8
Check that nothing remains attached to the cinder head likely to impede removal. It Is assumed that the head will be removed complete with exhaust manifold and inlet manifold lower section. 9 Unscrew the cylinder head bolts half a turn K
e
time in the reverse order to that shown in (lustration 10.20a. When the bolts are free. «mwe them from their locations.. Id Lift the cylinder head from the block. If it is stuck tight rock the head to break the joint by mans of the manifolds. On no account drive
levers
into the gasket Joint, nor attempt to tap tf« head sideways, as it is located on positioning dowels. 11 Remove and discard the cylinder head gasket.
JK'
l^. 9.22b ... then apply RTV gasket sealant to the cover plate contact face 12 Refer to Chapter 20 for cylinder head dismantling and inspection procedures. Preparation for refitting 13 The mating faces of the cylinder head and cylinder block must be perfectly dean 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 particular care when cleaning the piston crowns as the soft aluminium alloy is easily damaged. Make sure that the carbon is not allowed to enter the oil and water passages -this Is particularly important for the lubncahon system, as carbon could block the oil supply to the engine's components. Using adhesive tape and paper, seal the water, oil and bolt holes in the cylinder block. To prevent carbon entering the gap between the pistons and bores, smear a little 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 the pistons in the same way. 14 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 excessive, machining may be the only alternative to renewal. If warpage of the cylinder head gasket surface Is suspected, use a straight-edge to check it for distortion. Refer to Part 0 of this Chapter if necessary. 15 Check the condition of the cylinder head bolts, and particularly their threads, whenever they are removed. Wash the bolts In a suitable
sequence
9.24 Lubricate the cam followers and place them in position in their respective bores solvent, and wipe them dry. Check each bolt for any sign of visible wear or damage, renewing them if necessary.
Refitting 18 Before refitting the 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, 17 The now gasket should not be removed from its nylon cover until required for use. Fit Ihe gasket dry, and make sure that the mating surfaces on the head and block are perfectly clean. 18 Place the gasket on the cylinder block so that the word ALTO can be read from above. 19 Lower the cylinder head onto the block so that it locates on the positioning dowel. 20 The cylinder head bolt threads must be clean and lightly lubricated. Screw the bolts in finger-tight then working progressively and in the sequence shown, lighten all the cylinder head bolts to the Stage 1 torquo 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 the 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 during this stage ot tightening, to ensure accuracy (see Illustrations). 21 Reconnect the exhaust system front pipe to the manifold using a new flange gasket.
10.20b Tighten the cylinder head bolts to the Stago 1 torque setting ...