1998 FIAT PUNTO rain

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

2A*10 SOHC (8-valve) petrol engine in-car repair procedures
require cutting with a sharp Knife to release
the sump.
Clean away all old gasket material. Refitting
5
Wwn refitting, a bead of RTV silicone nsiant gasket 3 mm in diameter should be applied lo the sump flange. Fit the sump, screw in tha fixing screws and tighten to the spscabed torque. Note the flange end fixing
nuts
(see illustrations).
6
'//ait one hour for the gasket compound to henjai before filling with engine oil. 7 Refit the flywheel housing cover plate and tohaust system front pipe.
8
lower the vehicle to the ground and fill the eng'rewith oil (see Chapter 1A). Check the oil
fevai
alter running the engine for a few minutes.

13 Oil
pump and pick-up tube - >>>
removal,
inspection and ^ refitting ^
Removal 1 Drain tho engine oil and remove the sump adsswibed in Section 12.
%
Unscrew and remove the oil filter cartridge .
(see
Chapter 1A|. 3 Remove the timing belt as described In
Section A.
4
Lock
the crankshaft against rotat>on either by tfacng a block of wood between a crankshaft wb and the inside of the crankcase, or by jjmning the flywheel starter ring gear with a
lutabfe
tool.
I3v8a Removing the oil pump pressure relief valve
12.5a Tightening a sump fixing screw
5 Unscrew and remove the crankshaft sprocket boll and take off the sprocket. If it is tight, use two screwdrivers to lever it off, or use a two or three-legged puller. 6 Unbolt and remove the oil pick-up/filter screen assembly. Note the sealing washer. 7 Extract the oil pump fixing bolts and withdraw the pump. Remove the gasket.
Inspection 8 The oil pump incorporates a pressure relief valve, which can be removed for examination by depressing the spring plunger and pulling out the keeper plate (see illustrations). 9 If pump wear Is suspected, check the gears in the following way. Extract the fixing screws and remove the rear cover plate. The screws are very tight, and will probably require the use of an impact screwdriver (see illustration).
pressure relief valve
12.5b Sump fixing screw and flange end fixing nut
10 Check the clearance between the outer gear and the pump housing using feeler blades. Check the gear endtloat by placing a straightedge across the pump body, and checking the gap between the straight-edge and gear face (see illustrations). If the clearances are outside the specified tolerance, renew the oil pump complete. 11 If the pump is unworn, refit the rear cover plate and tighten the screws fully. 12 Apply air pressure from a tyre pump to the oil pump oil ducts, to clear any sludge or other material. Prime the pump by pouhng clean engine oil into its inlet duct, at the same time turning the oil pump inner gear with the fingers. 13 Lever out the oil seal and drive a new one squarely into the oil pump casing (see illustrations). Lubricate the oil seal lips.
13.9 Using an impact screwdriver to remove the oil pump rear cover pfate screws
13,19s Measuring oil pump outer gear-to- 13.10b Measuring oil pump gear endtloat pump housing clearance

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

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 ...

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
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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