1999 FIAT PUNTO oil type

2A«1
Chapter 2 Part A:
SOHC (8-valve) petrol
engine in-car repair procedures
Contents
Auxiliary drivebelts • removal and refitting See Chapter 1A Gamstaft cover - removal and refitting 6 Camshaft oil seal - renewal 7 Camshaft • removal and refitting See Chapter 20 Crankshaft oil seals - renewal 8 Cylinder compression test 3 Cylinder head - dismantling and overhaul See Chapter 20 Cylinder head - remove] and refitting 9 Engine mountings - Inspection and renewal 11 Engine oil and filter • renewal See Chapter 1A
Degrees of difficulty
Engine oil level check See Weekiy checks Flywheel/driveplate • removal, inspection and refitting 10 General Information 1 Location of TOC on No 1 cylinder 2 Oil pump and pick-up tube - removal, inspection and refitting 13 Sump • removal and refitting 12 Timing belt and covers • removal and refitting .. 4 Timing belt tensioner and sprockets - removal, inspection and refitting 5 Vafve clearance check and adjustment See Chapter 1A
Easy, suitable (or twics with little |g experience ^
Fairty easy, suitable jk for beginner with & some experience ^
Fatrty difficult, ^ suitable for competent ^ CKYmechanic ^
Difficult, suitable for ^ experienced DIY « mechanic ^
Veiy difficult, ^ aiitabte for expert DIY « or professional
Specifications
General Engine code:' 1108 cc engine (55 models): Up to May 1997 176.A6.000 May 1d97 onwards • . 176.B2.000 1242 cc engine (60 models): Up to May 1997 176.B1.000 May 1997 onward 176.B4.000 1242 cc engine (75 modete) 176.A8.000
•Note:
See Vehicle Identification for the location of code marking on the engine. 8cre: 11O0OC engine 70.0 mm 1242 cc engine 70.8 mm Stroke: 1108 cc engine 72.0 mm 1242 cc engine 78.86 mm Compression ratio: 1108 cc engine 9.6:1 1242 cc engine with single-point injection 9.6:1 1242 cc engine with multi-point injection 9.8:1 Rrlng order 1-3-4-2
No 1
cylinder location Timing belt end of engine
TnUng
belt tension See text
Lubrication system
Oil
pump type By-rotor driven from front of crankshaft Outer rotor-to-housing clearance 0.080to0.186mm
Axial
clearance 0.025 to 0.056 mm

2A*10 SOHC (8-valve) petrol engine in-car repair procedures
2.11 Unscrewing the crankshaft pulley bolts
6 Itae crankshaft sprocket Is also equipped •nth a timing mark - when this is aligned with 3relarence marking on the oil pump cover.
Hie
engine is set with cylinders No 1 and 4 at
TDC.
Note that it is the camshaft positioning that determines whether a cylinder is on its comcression or exhaust stroke.

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

2B»1
Chapter 2 Part B:
DOHC (16-valve) petrol
engine in-car repair procedures
Contents
Auxiliary drlvebelts - removal and refitting See Chapter 1A Camshaft oil seal - renewal 6 Camshafts and cam followers - removal, inspection and refitting .. 9 Crankshaft oil seals • renewal 7 Cylinder compression test 3 Cylinder head - dismantling and overhaul See Chapter 2D Cylinder head • removal and refitting 10 Cylinder head extension • removal and refitting 8 Engine assembly/Valve timing holes - general information and usage 2
Engine mountings - inspection and renewal 12 Engine oil and filter - renewal See Chapter 1A Engine oil level - check See Weekly checks Flywheel - removal, Inspection and refitting 11 General Information 1 Oil pump and pick-up tube - removal, inspection and refitting 14 Sump - removal and refitting 13 Timing belt and covers - removal and refitting 4 Timing belt tensioner and sprockets • removal and refitting 5
Degrees of difficulty

Easy,
sitable
for
J; Fairly
easy,
suitable Fairtydifflcutt, ^
Difficult,
aitabtefcr Very
difficult,
^ nwice
wim
(ttls for beginner with £
suitable
for competent KYmechanic ^ experienced DIY > suitable
for
expert DIY« experience
some
experience £
suitable
for competent KYmechanic ^ mechanic > or professional ^
Specifications
General Engine code* 176.09.000 •Note: See Vehicle Identification for the location of code marking on the engine. Bore 70.8 mm Stroke 78.86 mm Capacity 1242 cc Compression ratio 10.2:1 Firing order 1-3-4-2 No
1
cylinder location Timing belt end of engine Timing belt tension See text
Camshaft Orlve Toothed belt
No
of bearings 3 Camshaft bearing journal diameters: Ho
1
bearing 35.000 to 35.015 mm
Mo
2 bearing 48.000 to 48.015 mm No 3 bearing 49.000 to 49.015 mm Camshaft bearing Journal running clearance 0.030 to 0.070 mm Camshaft endfloat 0.15 to 0.34 mm
Cylinder head extension Camshaft bearing diamelers: No
1
bearing 35.045 to 35.070 mm No 2 bearing 48,045 to 48.070 mm No 3 bearing 49.045 to 49.070 mm
Cam
follower (tappet) type Hydraulic
Cam
follower (tappet) diameter 28.353 to 28.370 mm
Cam
follower (tappet) bore diameter in cylinder head extension 28.400 to 28.421 mm
Cam
follower (tappet) running clearance 0.046 to
0.051
mm

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

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

2C«1
Chapter 2 PartC:
Diesel engine in-car repair procedures
Contents
Auxiliary drivebelts - removal and refitting See Chapter 1B Camshaft cover - removal and refitting 6 Camshaft oil seal - renewal 7 Camshaft - removal and refitting See Chapter 20 Crankshaft oil seats - renewal 8 Cylinder compression test « 3 Cylinder head - dismantling and overhaul See Chapter 20 Cylinder head - removal and refitting 9 Engine mountings - inspection and renewal 11 Engine oil and fitter - renewal See Chapter 18 Engine oil level check See Weekly checks
Degrees of difficulty
Flywheel * removal, inspection and refitting 10 General information 1 Location of TDC on No 1 cylinder 2 Oil cooler - removal and refitting 14 Oil pump and pick-up tube • removal, Inspection and refitting 13 Sump • removal and refitting 12 Timing belt and covers • removal and refitting 4 Timing belt tensioner and sprockets - removal, Inspection and refitting 5 Valve clearance check and adjustment See Chapter 1B

Easy,
suitable for novice
with Irttle
|| experience g^
FaMy
eesy,
suitable ^
forbeglnnerwilti
some experience ^
Falrtydfficult, ^ suitable
for
competent DIYmechanic ^

Difficult, suitable
for & experienced DIY mechanic ^
Very
difficult,
^ suitable
for
expert
DfY
jR or professional ^
Specifications
General Engine code:' 1698 cc non-turbo engine 176.B3.000 1698 cc turbo engine: Up to 1997 t76.A3.00aor176.A5.000 1997 onward 176.A3.000or176.B7.000 •Note: See Vehicle Identification for the location of the code marking on the engine. Bore 82.6 mm Stroke 79.2 mm Compression ratio: Non-turbo engine 20.5:1 Turbo engine 19:1 Firing order 1-3-4-2
No 1
cylinder location Timing belt end of engine Titling belt tension See text
Lubrication system Oi pump type By-rotor driven from front of crankshaft Outer rotor-to-houslng clearance 0.080 to 0.186 mm Axial clearance 0.025 to 0.056 mm
Torque wrench settings Nm ibf ft Camshaft cover 10 7 Camshaft sprocket 11B 87 Crankshaft sprocket centre bolt 190 140 Cylinder head: Stage 1 50 37 Stage 2 100 74 StageS Angle-tighten a furtfier 90" Stage 4 Angle-tighten a further 90° CySnder head front bolts 30 22 Flywheel 142 105
Fuel
injection pump sprocket 49 36 Inlet and exhaust manifolds 25 18 Sump 10 7 Timing belt tensioner and idler 44 32

2C*2 Diesel engine in-car repair procedures
5.11 Special Fiat tool necessary to accurately position the camshaft before fitting the sprocket
Camshaft sprocket Removal 11 Remove the timing belt as descnbed in Section 4. A special Rat tool (see illustration) is necessary to position the camshaft before refitting the sprocket, however il the original camshafl Is being re-used, use of the special tool can be ovoided by accurately marking the camshaft position before removing the sprocket. Caution: On later 1996 models the camshaft sprocket can be moved In either direction on tho camshaft location dowel. 12 The camshaft sprocket must now oe held stationary whilst the retaining bolt is loosened. This is no problem on later models where the sprocket incorporates holes, however some early models have a sprocket without holes • on this type Fiat technicians use a special tool
V*— r^r
To make a camshaft sprocket holding tool, obtain two lengths of steel strip about 6 mm thick by 30 mm wide or simllar, one 600 mm long, the other 200 mm long (all dimensions approximate). Bolt the two strips together to form a forked end, leaving tho 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 futcrums; theso will engage with the cut'Outs In the sprocket, and should protrude by about 30 mm
which clamps on the sprockot teeth. If this tool is not available, it may be possible to make up a similar tool. On later models a sprocket holding tool can easily be made (see Toot Tip). 13 On 1996-on models mark the position of the camshaft in relation to the cylinder head.
5.14a Unscrew and remove the bolt and washer...
This is best achieved by removing tho vacuum pump from the flywheel end of the head and marking the head in relation to Ihe drive slot in ihe end of the camshaft. Note the location of the hose and bracket when removing tha vacuum pump (seo illustration). 14 Unscrew and remove tho boll and v/ashof and withdraw the sprocket from the end of tha camshaft (see Illustrations). Note tha location peg on the camshafl. Inspection 15 With the sprocket removed, examine the camshaft oil seal for signs of leaking. If necessary, rater to Section 7 and renew it 16 Check the sprocket teeth for damage. 17 Wipe clean the sprocket and camshaft mating surfaces-Refitting 18 Locate the sprocket on the end of the camshaft. On J996-on models chock that the camshaft is positioned accurately to tho previously made marks and also make sura thai the TOC mark on Ihe sprocket Is aligned with the mark on the Inner timing cover. If avoiiablo use the special Fiat toot to locate the camshaft correctly. Rofil the bolt and washer and tighten lo the specified torque while holding the camshalt sprocket stationary using the method descnbed previously. Recheck all alignment marks. 19 Refit the timing belt as described in Section 4.
Crankshaft sprocket Caution: The crankshaft sprockot retaining bolt has a left-hand thread. Removal 20 Remove the timing belt as described in Section 4. 21 Working beneath the engine unbolt and remove the flywheel lower cover, than hold the flywheel stationary preferably using a tool which engages the flywheel starter ring gear (see Section 10). Alternatively have an assistant engage a wide-bladed screwdriver with the starter ring gear 22 Unscrew and remove (he crankshaft sprocket retaining bolt (left-hand thread), washer and spacer and slide the sprocket off the end of the crankshaft (see illustrations). It is quite tight and il will be necessary to use a
5.14b ... and remove the sprocket from tho end of the camshaft 5.22a Unscrew and remove the bolt, washer and spacer... 5.22b ... and remove the crankshaft sprocket

2D*10 Engine removal and overhaul procedures
7.13 Positioning of piston rings (petrol engine) 11 Scrape away all traces of carbon from the top of the piston. A hand-held wire brush (or a piece of fine emery cloth) can be used, once the majority ot the deposits have been scraped away. 12 Remove the carbon from the ring grooves In the piston, using an old ring. Break the ring in half to do this (be careful not to cut your fingers - piston rings are sharp). Be careful to remove only the carbon deposits • do not remove any metal, end do not nick or scratch the sides of the ring grooves. 13 Once the deposits have been removed, clean the piston/connecting rod assembly with paraffin or o suitable solvent, and dry thoroughly. Make sure that the oil return holes In the ring grooves are clear. Fit the rings to their respective grooves meking sure they are positioned the correct way round where applicable (see illustration). 14 If the pistons and cylinder bores are not
7.22 Prising out the gudgeon pin retaining circilps damagea or worn excessively, and if the cylinder block does not need to be rebored. the original pistons can be refitted. Normal piston wear shows up as even vertical wear on the piston thrust surfaces, and slight looseness of the top ring In its groove. New piston rings should always be used when the engine is reassembled. 15 Carefully inspect each piston for cracks around the skirt, around the gudgeon pin holes, and at the piston nng lands (between the ring grooves). 16 Look for scoring and scuffing on the ptston skirt, holes in the piston crown, and burned areas at the edge of the crown. If the skirt is scored or scuffed, the engine may have been suffering from overheating, end/or abnormal combustion which caused excessively high operating temperatures. The cooling and lubrication systems should be checked thoroughly. Scorch marks on the sides of the pistons show that blow-by has occurred. A hole in the piston crown, or burned areas at the edge of the piston crown, Indicates that abnormal combustion has been occurring. If any of the above problems exist, the causes must be investigated and corrected, or the
7.26a Piston to connecting rod assembly (petrol engine) 1 Piston grade (A) end directional arrow on piston crown (towards timing belt end) 2 Connecting rod/cap matching numbers 3 Gudgeon pin offset in piston (0.9 to 1.1 mm) Arrow indicates direction of crankshaft rotation
7.26b Piston to connecting rod assembly (diesel engine) 1 Piston crown
damage will occur again. The causes may Include Incorrect Ignition/injection pump timing, or a faulty injector (as applicable). 17 Corrosion of the piston, in the form ol pitting, indicates that coolant has been leaking into the combustion chamber and/or the crankcase. Again, the cause must be corrected, or the problem may persist In the rebuilt engine. 16 Examine each connecting rod carefully for signs of damage, such as cracks around the big-end and small-end bearings. Check that the rod is not bent or distorted, Damage is highly unlikely, unless the engine has been seized or badly overheated. Detailed checking of the connecting rod assembly can only be earned out by an engine repair specialist with the necessary equipment. 19 Although not essential. It is highly recommended that the big-end cap bolts are renewed as a complete set prior lo refitting. 20 On petrol engines piston and/or con-necting rod renewal should be entrusted to an engine repair specialist, who will have the necessary tooling to remove and install the interference fit gudgeon pins. 21 On diesel engines, the gudgeon pins are of the floating type, secured in position by two circlips. On these engines, the pistons and connecting rods can be separated as follows. 22 Using a small fiat-bladed screwdriver, prise out ihe circlips, and push out the gudgeon pin (see illustration). Identify the piston and rod to ensure correct reassembly. Discard the circlips - new ones must be used on refitting. 23 Examine the gudgeon pin and connecting rod small-end bearing bush for signs of wear or damage. Bush renewal should be entrusted to an engine overhaul specialist. 24 The connecting rods themselves should not be In need of renewal, unless seizure or some other major mechanical failure has occurred. Check the alignment of the connecting rods visually, and if the rods are not straight, take ihem to an engine overhaul specialist for a more detailed check. 25 Examine all components, and obtain any new parts as necessary. If new pistons are purchased, they will be supplied complete with gudgeon pins and circlips. 26 On reassembly position the piston on the connecting rod as shown (see Illustrations),
Injection pump location Connecting rod/cap matching numbers 7.28c Piston crown on diesel engines