1999 FIAT PUNTO cooling

2D*10 Engine removal and overhaul procedures
1 General information
Included In (his Part of Chapter 2 are details of removing the engine/transmission from the car and general overhaul procedures for tho cylinder head, cylinder block/crankca9e and all other engine internal components. The information given ranges from advice concerning preparation for an overhaul and the purchase of replacement parts, to detailed step-by-step procedures covering removal, inspection, renovation and refitting of engine Internal components. After Section 5, all instructions are based on the assumption that the engine has been removed from the car. For Information concerning in-car engine repair, as well as the removal and refitting of those external components necessary for full overhaul, refer to Part A, 8 or C of this Chapter (as applicable) and to Section 5. Ignore any preliminary dismantling operations described in Part A. B or C that are no longer relevant onca the engine has been removed from ihe car.
2 Engine overhaul -general information
1 It Is not always easy to determine when, or if, an engine should be completely overhauled, as a number of lectors must be considered. 2 High mileage Is not necessarily an Indication that an overhaul Is needed, while low mileage does not preclude the need for an overhaul. Frequency of servicing Is probably the most important consideration. An engine which has had regular and frequent oil and filter changes, as well as other required maintenance, should give many thousands of miles of reliable service. Conversely, a neglected engine may require an overhaul very early In its life. 3 Excessive oil consumption Is an Indication that piston rings, vaivo seals and/or valve guides are in need of attention. Make sure that oil leaks are not responsible before deciding that the rings and/or guides are worn Perform a compression test, as described In Parts A or B (petrol engines) or C (diesel engines) of this Chapter, to determine the likely cause of the problem. 4 Check the oil pressure with a gauge fitted In place of the oil pressure switch. If it Is extremely low. the main and big-end bearings, and/or the oil pump, are probably worn out. 5 Loss of power, rough running, knocking or metallic engine noises, excessive valve gear noise, and high fuel consumption may also point to Ihe need for an overhaul, especially if
they are all present at the same time. If a complete service does not remedy the situation, major mechanical work is the only solution. 6 An engine overhaul involves restoring ell Internal parts to the specification of a new engine. During an overhaul, the cylinders are rebored (where applicable), the pistons and the piston rings are renewed. New main and big-end bearings are generally fitted; If necessary, the crankshaft may be reground. to restore the journals. 7 The valves are also servrced as well, since they are usually In less-than-perfect condition at this point. While the engine is being overhauled, other components, such as the starter and alternator, can be overhauled as well. The end result should be an as-new engine that will give many trouble-free miles. Note: Critical cooling system components such as the hoses, thermostat and coolant pump should be renewed when an engine is overhauled. The radiator should be checked carefully, to ensure that it is not clogged or leaking. A/so. it Is a good Idea to renew the ofI pump whenever the engine i$ overhauled.
8 Before beginning the engine overhaul, read through tho entire procedure, to familiarise yourself with the scope and requirements of the job. Overhauling an engine is not difficult If you follow carefully all of the instructions, have the necessary tools and equipment, and pay close attention to all specifications. It can, however, be time-consuming. Plan on the car being off the road for a minimum of two weeks, especially If pans must be taken to an engineering wo'kd for repair or reconditioning.
9 Check on the availability of parts and make sure that any necessary special tools and equipment are obtained in advance. Most work can be done with typical hand lools, although a number of precision measuring tools are required (or Inspecting parts to determine if they must be renewed. Often the engineering works will handle the inspection of parts and offer advice concerning reconditioning and renewal, Note: Always wait unt'l the engine has been completely dismantled, and until all components (especially the cylinder block/crankcase and the crankshaft) have been inspected, before deciding what service and repair operations must be performed by an engineering works. The condition of these components will be the major factor to consider when determining whether to overhaul the original engine, or to buy a reconditioned unit. Do not. fh ere tore, purchase parts or have overhaul work done on other components until they have been thoroughly Inspected. As a general rule, time is the primary cost of an overhaul, so it does not pay to fit worn or sub-standard parts.
10 As a final note, to ensure maximum life and minimum trouble from a reconditioned engine, everything must be assembled wilh care, in a spotlessly-clean environment.
3 Engine and transmission removal -methods
and
precautions
1 If you have decided that the engine must be removed for overhaul or major repair work, several preliminary steps should be taken. 2 Locating a suitable place to work is extremely important. Adequate work space, along with storage space for the car, will be needed. If a workshop or garage Is not available, at the very least, a flat, level, clean work surface Is required. 3 Cleaning the engine compartment and engine/transmission before beginning the removal procedure wilt help keep tools clean and organised. 4 An engine hoist or A-frame will also be necessary. Make sure the equipment is rated In excess of the combined weight of the engine and transmission, Safety Ib of primary Importance, considering the potential hazards involved in lifting the engine/transmission out of the car. 5 If this is Ihe first time you have removed
an
engine, an assistant Bhould Ideally be available. Advice and aid from someone more experienced would also be helpful. There are many instances when one person cannot simultaneously perform all of the operations required when lifting the engine out of Ihe vehicle. 6 Plan the operation ahead of time. Before starting work, arrange for the hire of or obtain all of the tools and equipment you will need. Some of the equipment necessary to perform engine/transmission removal and Installation safely and wilh relative ease On addition to an engine hoist) Is as follows: a heavy duly trolley jack, complete sets of spanners and sockets as described in the reference section of this manual, wooden blocks, and plenty of rags and cleaning solvent for mopping up spitted oil, coolant and fuel. If the hoist must be hired, make sure that you arrange for it In advance, and perform all of the operations possible without it beforehand. This will save you money and time.
7 Plan for the car to be out of use for quite a while. An engineering works will be required to perform some of the work which the do-it-yourselfer cannot accomplish without special equipment. These places often have a busy schedule, so it would be a good idea to consul! them before removing the engine, in order to accurately estimate the amount of time required to rebuild or repair components that may need work, 9 Always be extremely careful when removing and refitting the engine/transmission. Serious injury can result from careless actions. Plan ahead and take your time, and a job of this nature, although major, can be accomplished successfully.

2D*10 Engine removal and overhaul procedures
Engine and transmission -removal, separation, connection and refitting
Note: The engine Is lowered from the engine compartment as a complete unit with the transmission; tho two are then separated for overhaul.
Removal 1 Remove the bonnet and disconnect the washer tubing as described in Chapter 11 (see illustrations). 2 Apply the handbrake, then jack up the front of the vehicle and support on axle stands (see Jacking and vehicle support). Remove both front wheels. In order to remove tne engine/transmission assembly in an upright position from under the vehicle, there must be a minimum clearance of 660 mm between the floor and the front crossmember. Additional height Is necessary if the assembly is to be lowered onto a trolley. 3 Where fitted, unbolt and remove the engine compartment lower cover. 4 Remove the auxiliary drivebelt(s) with reference to Chapter 1A or 1B. 5 Dram the engine oil. transmission oil/fluid and coolant with reference to Chapter 1A or 1B. 6 Remove the battery (see Chapter 5A). 7 On manual transmission models with a cable dutch, disconnect the clutch cable from the transmission (refer to Chapter 6). On manual transmission models with a hydraulic clutch unbolt the clutch slave cylinder from the top of the transmission then fit a cable-tie around it to prevent the piston coming out (see Illustration). Position the cylinder to one side. 8 Unscrew the nut and disconnect the earth lead from the transmission (see illustration). Petrol engines 9 Unbolt and remove the battery tray. 10 Disconnect the wiring from the reversing light switch. 11 On manual transmission models disconnect the reverse Inhibition cable from the transmission then disconnect the gear selector rod from the lever on the transmission. 12 Remove the air cleaner and ducting as descnbed In Chapter 4A or 4B. 13 On automatic transmission models disconnect the kickdown cable and gear selector cable as described in Chapter 7B. Also disconnect the wiring for the electro-magnetic clutch. 14 Unbolt and remove the cover from the bulkhead then disconnect the oxygen sensor wiring. 15 Disconnect the remaining wiring at the bulkhead and release the fuse holders at the mounting. 16 Disconnect the vacuum pipe from the inlet manifold, and also disconnect the wiring connector located next to it.
4.1a Unscrewing the bonnet hinge bolts
17 Unscrewthenutsandseparatetheengine wiring harness lead from the battery positive cable terminal. 18 Disconnect the accelerator cable from the engine as described in Chapter 4A or 4B, 19 Loosen the clip and disconnect the radiator top hose from the elbow on the left-hand end of the cylinder head. Similarly disconnect the bottom hose. On 16-valve models, remove the radiator electric cooling fan as described in Chapter 3. 20 Identify the hoses connected to the throttle housing, then disconnect them. 21 Identify the coolant heater hoses on the bulkhead for position, then loosen the clips and disconnect the hoses. 22 Loosen the clip and disconnect the brake servo vacuum hose from the Inlet manifold. Where applicable, disconnect the remaining emission control system vacuum hoses from the Inlet manifold after Identifying their locations to aid refitting. 23 Disconnect tho fuel supply and return hoses from the throttle housing. 24 Release the connector from the ignition/fuel ECU located on the right-hand side of the engine compartment. 25 Unscrew the nut and detach the earth cable from its location near the ECU. 26 Disconnect the diagnostic connector located near the ECU. 27 On models fitted with power steering, refer to Chapter 10 and unbolt the power steering pump from the front of the engine without disconnecting the hydraulic fluid lines then tie It to one side so that it will not obstruct the removal of the engine. On
4.1b Disconnecting the washer tubing
models with air conditioning, similarly unbolt the air conditioning compressor and position it clear of the engine. Do not disconnect the air conditioning refngerant pipes/hoses. 26 On manual transmission models pull out the retaining plate and disconnect the gear selector cable from the lever on the transmission. 29 Unscrew the nuts retaining the track rod ends on the swivel hubs and use a balljoint separator tool to disconnect them. 30 Release the flexible brake fluid hoses and ABS system sensor wrring from the front suspension struts. 31 On manual transmission models, unscrew the nuts from the outer ends of each driveshaft. To prevent the hubs from turning either have an assistant depress the brake pedal, or temporarily Insert two wheel bolts and use a lever to hold the hub. 32 On automatic transmission models use a suitable drift to drive out Ihe roll pins securing 2D the inner ends of the drlveshafts to tho trans-mission output stubs. Turn the driveshalts as necossary to access the roll pins . 33 Unscrew the two bolts securing the right-hand swivel hub assembly to the front suspension strut, then move the hub assembly outwards. On manual transmission models release the outer end of the driveshaft from the hub assembly - on automatic transmission models slide the inner end of the driveshaft off the final drive output stub. Take care not to strain the flexible brake hose while doing this. Move the driveshaft to one side thon temporanly refit the hub assembly to the strut. On manual transmission models, make
^ - / //
4.7 Fit a cable tie around the dutch slave cylinder to prevent the piston coming out 4.8 Disconnecting the earth lead from the transmission

2D*10 Engine removal and overhaul procedures
4.50b ... and expansion tank 4.S2 Disconnecting the radiator coolant temperature sensor wiring plug
4.53b One of tho wheel arch liner retaining screws is hidden in a recess 52 On the radiator cooling fan housing, disconnect the wiring plug for tho coolant temperature sensor (see illustration). 53 Unscrew the four front screws on each side retaining the wheel arch liners in order to
4.53c Bolt securing the front bumper to the valance access the front bumper mounting bolts • one of lite screws is hidden in a recess. Pull back the liners and use an extension and socket to unscrew the bolts securing the front bumper to tho valance (see illustrations).
4.55 Releasing the retaining clips from the rear of tho indicator lights 4.56a Side bumper retaining screw
4.56b Centre bumper retaining screw 4.57a Radiator lower mounting bracket bolt
4.54 One of the front bumper lower retaining screws 54 Unscrew and remove the front bumper lower retaining screws (see Illustration). 55 From inside the engine compartment, disconnect the wiring from the rear of the Indicator lights and release the retaining clips (see illustration). 56 Unscrew the upper retaining screws and withdraw the front bumper from the body (see Illustrations). 57 Unscrew the bolts socunng the radiator lower mounting bracket to the body then prise the bracket from the rubbers on the bottom ol the radiator (see Illustrations). 58 Unscrew the upper mounting bolt securing the engine oil cooler then lower the cooler and support on an axle stand (see illustrotion). Take care not to damage the hoses. 59 Support the radiator then unscrew the radiator upper mounting bolts, and remove the radiator from the vehicle (see illustrations).
4.57b Removing the bracket from the rubbers on the bottom of the radiator

2D*10 Engine removal and overhaul procedures
05 Remove the brush holder assembly from the automatic transmission as described in Chapter 7B, Section 4. The brushes bear on the slip rings at the rear of the electro-magnetic clutch housing and they may be damaged when the transmission is removed. 86 Unscrew and remove the transmission-to-engine bolts then carefully draw the transmission away from the engine, resting It securely on wooden blocks. Collect the locating dowels If they are loose enough to be extracted, 87 If the oil pump driveshaft remains engaged with the crankshaft, remove it and reert Into the transmission to protect It from damage.
Connection 86 If the engine and transmission have not been separated, go to paragraph 104. Manual transmission models 89 Smear a little high-melting-point grease
on
the splines of the transmission input shaft. Do not use an excessive amount as there Is the risk of contaminating the clutch friction plate. 90 Carefully offer up the transmission to the engine cylinder block, guiding the input shaft through the clutch friction plate. 91 Refit the transmission-to-engine bolts and
the
single nut. hand^jghtenlng 1hem to secure the transmission in position. Note: Do not hghten them to force the engine and transmission together. Ensure that the beilhousing and cylinder block mating faces will butt together evenly without obstruction, before finally tightening the bolts and nut securely. Automatic transmission models 92 Check that the oil pump driveshaft is correctly engaged with the oil pump in the transmission. 93 Carefully offer up the transmission to Ihe rear of the engine and insert the oil pump driveshaft In the centre of the electro-magnetic clutch housing. Locate the transmission on the locating dowels then Insert the bolts and tighten them securely. 94 Refit the brush holder assembly to the automatic transmission with reference to Chapter 7B, Section 4. Petrol engines 96 Refit the transmission lower cover and tighten the bolts. 96 Locate the support bracket on the lower cover, then insert the bolts hand-tight. Also Insert the bolts securing the bracket lo the rear of Ihe cylinder block. With all the bolts Inserted, tighten them securely. 97 Refit the earth leads and tighten the bolts. Diesel engines 98 Refit the rpm sensor and tighten the bolts. 99 Insert the Intermediate shaft through the bracket then locate the dust boot on it and insert the Inner end in the transmission.
100 Refit and tighten the bolts securing the Intermediate shaft to the bracket on the rear of the cylinder block. 101 Refit the transmission lower cover and tighten the bolts. Ail models 102 Refit the starter motor (see Chapter 5A). 103 Refit the wiring harness to the components on the engine/transmission assembly making sure it is routed correctly.
Refitting 104 Locate the engine/transmission assembly beneath the engine compartment and attach the hoist to the lifting eyes. 105 Carefully lift the assembly up into the engine compartment taking care not to damage the surrounding components. 106 Reconnect the left-hand engine/trans-mission mounting to the body and tighten the bolts. 107 Reconnect Ihe right-hand engine mounting to the body and tighten the bolts. 108 Working beneath the vehicle, refit the rear engine mounting and tighten the bolts. 109 Disconnect the hoist from the engine and transmission lifting eyes and remove the hoist from under the vehicle. 110 The remainder of the refitting procedure is the direct reverse of the removal procedure, noting the following points:
a) Ensure that alf sections of the wiring harness follow their original routing; use new cable-ties to secure the harness In position, keeping it away from sources
of
heat and abrasion. b) On vehicles with manual transmission check and if necessary adjust the gearchenge cable and rod with reference to Chapter 7A. c) On vehicles with automatic transmission use new ro//p/ns fo secure the driveshafts to the transmission output stubs. Also check and if necessary adjust the kickdown end selector cables with reference to Chapter 78. d) Ensure that afi hoses are correctly routed and are secured with the correct hose clips, where applicable. If the hose clips cannot be used again; proprietary worm drive clips should be fitted
In
their place. e) Refill the cooling system as described in Chapter 1A or 18. f) Refill the engine with appropriate grades and quantities of oil (Chapter
1A
or 1B). g) Refit and adjust the auxiliary drivebelt(s) wfth reference fo Chapter 1A or 1B. h) Check and If necessary adjust the accelerator cable with reference to Chapter
AA,
48 or
AC.
i) When the engine is started for the first time, check for
air,
coolant, lubricant and fuel leaks from manifolds, hoses etc. If
the
engine has been overhauled, read
the
notes In Section 13 before attempting to starlit.
5 Engine overhaul • dismantling sequence
1 It is much easier to dismantle and work on the engine if it is mounted on a portable engine stand. These stands can often be hired from a tool hire shop. Before the engine is mounted on a stand, the flywheel should be removed, so that the stand bolts can be tightened Into the end of the cylinder block/crankcase. 2 If a stand Is not available, it Is possible to dismantle the engine with it blocked up on a sturdy workbench, or on the floor, Be very careful not to tip or drop the engine when working without a stand. 3 If you intend to obtain a reconditioned engine, all anclllarles must be removed first, to be transferred to the replacement engine (just as they will If you are doing a complete engine overhaul yourself). These components Include the following:
Petroi engines a) Power steering pump if removed with the engine (Chapter
10).
b) Alternator fmcluding mounting brackets) and starter motor (Chapter
SA).
c) The Ignition system and HT components including ail sensors, HT leads and
spark
plugs (Chapters 1A and
SB).
d) The fuel injection system components (Chapters A A and
AB).
e) All electrical switches, actuators and sensors, and the engine wiring harness (Chapters 4A, AB, SB). f) Inlet and exhaust manifolds (Chapters 4A, AB end
AD).
g) Engine oil dipstick and tube. h) Engine mountings (Chapter
2A).
i) Flywheef/driveptate (Chapter
2A).
j) Clutch components (Chapter
6)
- manual transmission. k) Electro-magnetic clutch components (Chapter 7B) - automatic transmission. I) Cooling system components (Chapter
3).

Diesei engines a) Power steering pump //removed with the engine (Chapter
10).
b) Alternator (Including mounting brackets) and starter motor (Chapter 5A). c) The glow plugfpre-heatlng system components (Chapter
SC).
d) Ait fuel system components, including the fuel injection pump, all sensors and actuators (Chapter
AC).
e) The vacuum pump. f) Ail electrical switches, actuators and sensors, and the engine wiring harness (Chapter 4C and 5C). g) Inlet and exhaust manifolds and, where applicable, the turbocharger (Chapter
AC
and 4D). h) The engine oil level dipstick and its tube. i) Engine mountings (Chapter
2C).

2D*10 Engine removal and overhaul procedures
6.5s Prising out the feed stub of the camshaft lubricating pipe J) Flywheel (Chapter 2C). k) Clutch components (Chapter
6).
I) Cooling system components (Chapter
3).
Note: When removing trie external components from the engine, pay close attention to details that may be helpful or important during refitting. Note the fitted position of gaskets, seals, spacers, pins, washers, bolts, and other small components. 4 If you are obtaining a short engine (the engine cylinder block/crankcase, crankshaft, pistons and connecting rods, all fully assembled), then the cylinder head, sump, oil pump, timing belt (together with its tensloner and covers), coolant pump, thermostat housing, coolant outlet elbows, oil filter housing and where applicable oil cooler will also have to be removed. 5 If you are planning a full overhaul, the engine can be dismantled in the order given below: $) Ftywhaoi/drivoplate.
6.5d When removing the camshaft bearing caps, note the position of the (ong and short locating dowels
bearing/banjo union bolt b) Timing belt, sprockets, and tensioner. c) Inlet and exhaust manifolds. d) Cylinder head. e) Sump. f) Oil pump. g) Pistons and crankshaft.
6 Cylinder head - % dismantling, cleaning, inspection and reassembly ^
Note: Now and reconditioned cylinder heads are available from the manufacturer or engine overhaul specialists. Be aware that some specialist tools are required for the dismantling and inspection procedures, and new com-ponents may not be readily available. It may therefore be mors practical and economical for the home mechanic to purchase a reconditioned head, rather than dismantle, inspect and recondition the original head.
Dismantling Note: On 8-valve petrol engines and diesel engines, the camshaft and cam followers are /oca fed In the cylinder head assembly and the relevant dismantling and reassembly procedures are contained in this Section. On 1$-valve petrol engines, the camshafts and cam followers are /oca fed In a separate housing (cylinder head extension) which is bo/fed fo the top of the cylinder head. All procedures relating to the camshafts and cam followers on 16-valve engines are therefore contained in Chapter 2B. Proceed fo paragraph 15 for cylinder head dismantling
6.8a Unscrew and remove the bolts from the thermostat housing, noting the location of the bracket
6.5c Removing the camshaft lubricating pipe procedures on /6-vafve engines, and ignore any references to camshafts, cam followers and oil seals in the paragraphs that follow. 1 Remove the cylinder head as described in Part A. B or C of this Chapter (as applicable). 2 If not already done, remove the inlet and exhaust manifolds with reference to the relevant Part of Chapter 4. Also remove the spark plugs, glow plugs and injectors as applicable. 3 Remove the camshaft sprocket with reference to Chapter 2A or 2C. Petrol engines 4 Mark the positions of the camshaft bearing caps, numbering them from the timing end. 5 Unbolt and remove the lubrication pipe (prise the oil feed stub out with a screwdriver). Unscrew the remaining bolts and take off the bearing caps (see illustrations). 6 Lift the camshaft carefully from the cylinder head, checking lhat the valve clearance shims and cam followers are not withdrawn by the adhesion of the oil (see Illustration). 7 Remove the shims and cam followers, but keep them In their originally fitted order. Diesel engines 8 Unbolt the thermostat housing and gasket, and vacuum pump from the left-hand end of the cylinder head. Also if necessary unbolt the coolant cover and gasket from the right-hand end of the head. Note the location of brackets (see illustrations) 9 Using a soft metal drift, carefully lap out the left-hand side mount and recover the gasket (soe illustrations). 10 At tho timing bait end of the cylinder head.
6.8b Removing the thermostat housing ... 6.6 Removing the camshaft

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

3*1
Chapter 3
Cooling, heating and ventilation systems
Contents
Air conditioning system - general Information and precautions .... 9 Mr conditioning system components * removal and refitting 10 Antifreeze mixture See Chapter 1A or 1B Auxiliary drivebell(s) check and renewal See Chapter 1A or IB Coolant level check See Weekly checks Coolant pump - removal, Inspection and refitting 7 Coolant renewal See Chapter 1A or 1B
Degrees of difficulty
Cooling fan switch - testing, removal and refitting 6 Cooling system hoses • disconnection and renewal 2 Electric cooling fan(s) - testing, removal and refitting 5 General information and precautions 1 Heater/ventilation components • removal and refitting 8 Radiator - removal, inspection and refitting 3 Thermostat - removal, testing and refitting 4

Easy,
suitable foe JS^, novice
with
little experience ^
Fairly
easy,
sutable for beginner witti
some experience
^
Faiilydifltctit,
suitable
for competent
DIY mechanic
^

Difficult,
sutable for & experienced DIY « mechanic ^
VerydMlcult, ^
suitable
for
expert DIY
« or professional
Specifications
General Expansion tank relief valve opening pressure 0.96 bar Coolant pump Impeller-to-casing clearance: Diesel engine models 0.53 to 1.37 mm Petrol engine models 0.4 to 0.9 mm
Thermostat Diesel engine models: Opening temperature: Starts to open 78 to 82*0 Fully open 88°C Maximum valve travel (approximate) 7.5 mm Petrol engine models: Opening temperature: 1108 cc and 1242 cc (8-valve) engines: Starts to open 85 to 89°C Fully open 100°C 1242 cc (16-valve) engines: Starts to open 81 to 85°C Fully open 103°C Maximum valve lift (approximate) 7.5 mm
Electric cooling fan Petrol engine models with single speed fan: Cut-in temperature 90to94°C Cut-out temperature B5 to 89°C Diesel engine models with twin speed fan: Cut-In temperature: Primary fan 86 to 90® C Secondary fan 90 to 94°C Cut-out temperature: Primary fan 81to85°C Secondary fan 85 to 89°C
Torque wrench settings Nm tbfft Coolant pump pulley securing bolts (diesel engine models) 23 17 Coolant pump securing bolts: Diesel engine models 23 17 Petrol engine models 8 6 Coolant pump securing nuts (petrol engine models) 10 7

3*2 Cooling, heating and ventilation systems
1 General information and precautions
Genera/ Information The engine cooling/cabin heating system is ol pressurised type, comprising a coolant pump driven by the camshaft timing belt (petrol engine models) or auxiliary drlvebelt (diesel engine models), a crossllow radiator, a coolant expansion tank, an electric cooling fan, a thermostat, heater matrix, and all associated hoses and switches. The system functions as follows: Ihe coolant pump circulates cold water around the cylinder block and head passages, and through the Inlet manifold, heater matrix and throttle body to the thermostat housing. When the engine Is cold, the thermostat remains closed and prevents coolant from circulating through the radiator. When the coolant reaches a predetermined temperature, the thermostat opens, and the coolant passes through the top hose to the radiator. As the coolant circulates through the radiator, it is cooled by the in-rush of air when the car is in forward motion. The airllow is supplemented by the action of the electric cooling fan. when necessary, As the temperature of the coolant in the radiator drops, it flows to the bottom of the radiator by convection, and passes out through the bottom hose to the coolant pump - the cycle is then repeatod, When the engine is at normal operating temperature, the coolant expands, and some of It is displaced into the expansion tank. Coolant collects In the tank, and ts returned to Ihe radiator when the system cools. On petrol engine models, the expansion tank is integrated into the side of the radiator. On diesel engine models, and certain petrol engine models with air conditioning, the tank is a separate unit, mounted on the right hand side of the engine compartment. On turbo diesel engine models, the coolant is also passed through a supplementary engine oil cooler, to assist In controlling the engine lubricant temperature. Tho electric cooling fan mounted in front of the radiator is controlled by a thermostatic switch. At a predetermined coolant temperature, the swilch/sensor actuates the tan lo provide additional airflow through the radiator, The switch cuts the electrical supply to the Ion when the coolant temperature has dropped below a preset threshold (see Specifications).
Precautions

A


Warning: Do not attempt to remove the expansion tank pressure cap, or to disturb any part of the cooling system, whlio the engine is hot, as then is a high risk of scalding, tf the expansion tank pressure cap must be removed before the
engine and radiator have fulty cooled (even though this is not recommended?, the pressure in the cooling system must first be relieved. Cover the cap with a thick layer of cloth, to avoid scalding, and slowly unscrew the pressuro cap until a hissing sound Is heard. When the hissing stops, indicating that the pressure has reduced, slowly unscrew the pressure cap until it can be removed; If more hissing sounds are heard, wait until they have stopped before unscrewing the cap completely. At all times, keep your face well away from the pressure cap opening, and protect your hands.

A


Warning: Do not allow antifreeze to come into contact with your skin, or with the painted surfaces of the vehicle. Rinse off spills immediately, with plenty of water. Never leave antifreeze lying around in an open container, or In a puddle In the driveway or on the garage floor. Children and pets are attracted by its sweet smell, but antifreeze can be fatal tf ingested.

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Warning: If the engine is hot, the electric cooling fan may start rotating even if the engine and ignition are switched off. Be careful to keep your hands, hair, and any loose clothing well clear when working In the engine compartment.
2 Cooling system hoses - f&> disconnection and renewal ^
1 The number, routing and pattern of hoses will vary according to model, but the same basic procedure applies. Before commencing work, make sure that the new hoses are to hand, along wilh new hose clips if needed, it is good practice to renew the hose clips at the same time as the hoses. 2 Drain the cooling system, as described in Chapter 1A or 18, saving the coolant if it is fit for re-use. Apply a little penetrating oil onto the hose clips if they are corroded. 3 Release the hose clips from the hose concerned. Three types of clip are used; worm-drive. spring and 'sardine-can'. The worm-drive clip is released by turning its screw anti-clockwise. The spring clip Is released by squeezing Its tags together with pliers, at the same time working the cbp away from the hose stub. The sardine-can clips are not re-usable, and are best cut off with snips or side cutters. 4 Unclip any wires, cables or other hoses which may be attached to the hose being removed. Make notes for reference when reassembling If necessary. 5 Release the hose from its stubs with a twisting motion. Be careful not to damage the stubs on deltcate components such as the radiator, or thermostat housings. If the hose Is stuck fast, the best course is often to cut it off using a sharp knife, but again be careful not to damage the stubs.
6 Before fitting the new hose, smear the stubs with washing-up liquid or a suitable rubber lubricant to aid fitting. Do not use oil or grease, which may attack the rubber. 7 Fit the hose clips over the ends of the hose, then fit the hose over its stubs. Work the hose Into position. When satisfied, locate and tighten the hose dips. 6 Refill the cooling system as described In Chapter 1A or 1B. Run the engine, and chock that there are no leaks. 9 Recheck the tightness of Ihe hose clips on any new hoses after a few hundred miles. 10 Top-up the coolant level if necessary.
3 Radiator -
removal,
inspection and refitting
Removal Note: If leakage is the reason for removing
the
radiator, bear In mind that minor leaks can often be cured using proprietary radiator sealing compound, with the radiator in situ. 1 Disconnect the battery negative terminal (refer to Disconnecting the battery In the Reference Section of this manual). On diesel engine models, unbolt the relay bracket from the side of the battery tray. 2 Drain the cooling system as described In Chapter 1A or 1B. 3 On 1242 cc (16-valve) petrol engine models, remove the air cleaner and Inlet ducts as desenbed In Chapter 4B, 4 Slacken the clips and disconnect Ihe (op and bottom coolant hoses from the radiator. In addition on diesel engine models, and petrol engine models with a remotely-sited expansion tank, disconnect the expansion tank coolant hose from the right hand side ol the radiator (see Illustrations), 5 Unscrew the fixings and lift the plastic trim panel from above the front bumper Unscrew the bolt(s) securing tho radiator to the upper body panel (see Illustration). Note that the radiator and cooling fan assembly share the same upper mounting bolt. 6 Unbolt the cooling fan(e) and shroud assembly from Ihe rear ot the radiator, as described in Section 5.
3.4a Slacken the clip and disconnect the radiator bottom hose