Chapter 1 Routine maintenance and servicing
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Chapter 1 Routine maintenance and servicing

Chapter 1 Routine maintenance and servicing Chapter 1 Routine maintenance and servicing

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11.07.2015 Views

1595Ford Fiesta Remake2A•4 HCS engine in-car repair procedures4.6a Engage tags of rocker cover gasketinto the cut-outs in the coverRefitting5 Thoroughly clean the rocker cover, andscrape away any traces of old gasketremaining on the cover and cylinder headmating surfaces.6 Fit a new gasket to the rocker cover, thenrefit the rocker cover (see illustrations).Tighten the cover retaining bolts to thespecified torque wrench setting, in a diagonalsequence.7 Reconnect the HT leads, and refit the aircleaner as described in Chapter 4.5 Valve clearances -checking and adjustment2Note: The valve clearances must be checkedand adjusted only when the engine is cold.1 The importance of having the valveclearances correctly adjusted cannot beoverstressed, as they vitally affect theperformance of the engine. If the clearancesare too big, the engine will be noisy(characteristic rattling or tapping noises) andengine efficiency will be reduced, as thevalves open too late and close too early. Amore serious problem arises if the clearancesare too small, however. If this is the case, thevalves may not close fully when the engine ishot, resulting in serious damage to the engine(eg. burnt valve seats and/or cylinder headwarping/cracking). The clearances arechecked and adjusted as follows.2 Set the engine to TDC for No 1 piston, asdescribed in Section 3.3 Remove the rocker cover as described inSection 4.4 Starting from the thermostat end of thecylinder head, the valves are numbered asfollows:Valve NoCylinder No1 - Exhaust 12 - Inlet 13 - Exhaust 24 - Inlet 25 - Inlet 36 - Exhaust 37 - Inlet 48 - Exhaust 44.6b Refitting the rocker cover5 Adjust the valve clearances following thesequence given in the following table. Turnthe crankshaft pulley 180º (half a turn) afteradjusting each pair of valve clearances.Turning the engine will beeasier if the spark plugs areremoved first - see Chapter 1.Valves “rocking” Valves to adjust7 and 8 1 (exhaust), 2 (inlet)5 and 6 3 (exhaust), 4 (inlet)1 and 2 8 (exhaust), 7 (inlet)3 and 4 6 (exhaust), 5 (inlet)6 The clearances for the inlet and exhaustvalves differ (refer to the Specifications). Use afeeler gauge of the appropriate thickness tocheck each clearance between the end of thevalve stem and the rocker arm (seeillustration). The gauge should be a firmsliding fit between the valve and rocker arm.Where adjustment is necessary, turn theadjuster bolt as required with a ring spannerto set the clearance to that specified. Theadjuster bolts are of stiff-thread type, andrequire no locking nut.7 On completion, refit the rocker cover asdescribed in Section 4.6 Cylinder head rocker gear -removal, inspection and 2refittingRemoval1 Remove the rocker cover as described inSection 4.2 Unscrew the four retaining bolts, and lift therocker gear assembly from the cylinder head.As the assembly is withdrawn, ensure that thepushrods remain seated in their positions inthe engine.Inspection3 To dismantle the rocker shaft assembly,extract the split pin from one end of the shaft,then withdraw the spring and plain washersfrom the shaft.4 Slide off the rocker arms, the supportpedestals and coil springs from the shaft, but5.6 Adjusting the valve clearancesIf the pushrods are to be removed,keep them in the correct order of fittingby labelling them 1 to 8, starting fromthe thermostat end of the cylinderhead, or locate them in a card.take care to keep them in their original orderof fitting (see illustration).5 Clean the respective components, andinspect them for signs of excessive wear ordamage. Check that the oil lubrication holes inthe shaft are clear.6 Check the rocker shaft and arm pads whichbear on the valve stem end faces for wear andscoring, and check each rocker arm on theshaft for excessive wear. Renew anycomponents as necessary.Refitting7 Apply clean engine oil to the rocker shaftprior to reassembling.6.4 Rocker shaft partially dismantled forinspection

HCS engine in-car repair procedures 2A•56.8 Flat on the rocker shaft (arrowed) tosame side as rocker arm adjusting screws8 Reassemble in the reverse order ofdismantling. Make sure that the “flat” on therear end of the rocker shaft is to the same sideas the rocker arm adjusting screws (closest tothe thermostat end of the cylinder head whenfitted) (see illustration). This is essential forthe correct lubrication of the cylinder headcomponents.9 Refit the rocker shaft assembly. As it isfitted, ensure that the rocker adjuster screwsengage with their corresponding pushrods.10 Refit the rocker shaft retaining bolts,hand-tighten them and then tighten them tothe specified torque wrench setting. As theyare tightened, some of the rocker arms willapply pressure to the ends of the valve stems,and some of the rocker pedestals will notinitially be in contact with the cylinder head -these should pull down as the bolts aretightened to their specified torque. If for anyreason they do not, avoid the temptation toovertighten in order to pull them into position;loosen off the bolts, and check the cause ofthe problem. It may be that the rocker adjusterscrews require loosening off in order to allowthe assembly to be tightened down asrequired.11 Adjust the valve clearances as describedin Section 5.7 Cylinder head -removal and refitting 3RemovalNote: The following procedure describesremoval and refitting of the cylinder headcomplete with inlet and exhaust manifolds. Ifwished, the manifolds may be removed first,as described in the relevant Part of Chapter 4,and the cylinder head then removed on itsown.1 On fuel injection engines, depressurise thefuel system as described in Chapter 4, Part B.2 Disconnect the battery negative (earth) lead(refer to Chapter 5A, Section 1).3 Refer to Chapter 4A or 4B as applicableand remove the air cleaner.4 Refer to Section 4 and remove the rockercover.5 Refer to Chapter 1 and drain the coolingsystem.6 Disconnect the hoses from the thermostathousing.7 Disconnect the heater (coolant) hoses fromthe inlet manifold and CFi unit, whereapplicable.Whenever you disconnectany vacuum lines, coolant oremissions hoses, wiringconnectors and fuel lines,always label them clearly, so that theycan be correctly reassembled. Maskingtape and/or a touch-up paint applicatorwork well for marking items. Takeinstant photos, or sketch the locationsof components and brackets.8 Disconnect the accelerator and chokecables as applicable (see Chapter 4A or 4B).9 Disconnect the vacuum and breather hosesfrom the carburettor/CFi unit, and inletmanifold as applicable.10 Disconnect the fuel feed and return linesat the carburettor, or at the quick-releasecouplings, then unclip the fuel hoses from theinlet manifold; use rag to soak up any spiltfuel.11 Disconnect the HT leads from the sparkplugs and the support bracket. Unscrew andremove the spark plugs.12 Disconnect the electrical leads from thetemperature gauge sender, radiator coolingfan, the engine coolant temperature sender,and the anti-run-on (anti-dieselling) valve atthe carburettor.13 Disconnect the remaining wiring multiplugsfrom the engine sensors at the inletmanifold and from the oxygen sensor (wherefitted) in the exhaust manifold or downpipe.14 On vehicles equipped with a pulse-airsystem, remove the pulse-air piping and filterassembly as described in Chapter 4E.15 Chock the rear wheels then jack up thefront of the car and support it on axle stands(see “Jacking and Vehicle Support”).16 Undo the retaining nuts and bolts, anddisconnect the exhaust downpipe from themanifold. Remove the flange gasket. (Notethat both the gasket and the joint self-lockingnuts must be renewed.) To prevent theexhaust system from being strained, tie thedownpipe up using strong wire or a length ofcord to support it. Lower the vehicle.17 Undo the four retaining bolts and lift clearthe rocker gear assembly from the cylinderhead.18 Lift out the pushrods. Keep them in orderof fitting by labelling them 1 to 8, starting fromthe thermostat end of the cylinder head.Alternatively, push them through a piece ofcard in their fitted sequence.19 Progressively unscrew and loosen off thecylinder head retaining bolts in the reversesequence to that shown for tightening (seeillustration 7.27a). When they are allloosened off, remove the bolts, then lift thecylinder head clear and remove the gasket. Ifit is stuck, tap it upwards using a hammer andblock of wood. Do not try to turn it, as it islocated by dowels; make no attemptwhatsoever to prise it free using a screwdriverinserted between the block and head faces.The gasket must always be renewed; it shouldbe noted that the cylinder head retaining boltsmay be re-used, but only once. They shouldbe marked accordingly with a punch or paintmark. If there is any doubt as to how manytimes the bolts have been used, they must berenewed.20 To dismantle/overhaul the cylinder head,refer to Part D of this Chapter. It is normal forthe cylinder head to be decarbonised and thevalves to be reground whenever the head isremoved.Preparation for refitting21 The mating faces of the cylinder head andcylinder block must be perfectly clean beforerefitting the head. Use a hard plastic or woodscraper to remove all traces of gasket andcarbon; also clean the piston crowns. Takeparticular care during the cleaning operations,as aluminium alloy is easily damaged. Also,make sure that the carbon is not allowed toenter the oil and water passages - this isparticularly important for the lubricationsystem, as carbon could block the oil supplyto the engine’s components. Using adhesivetape and paper, seal the water, oil and boltholes in the cylinder block.To prevent carbon enteringthe gap between the pistonsand bores, smear a littlegrease in the gap. Aftercleaning each piston, use a small brushto remove all traces of grease andcarbon from the gap, then wipe awaythe remainder with a clean rag.22 Check the mating surfaces of the cylinderblock and the cylinder head for nicks, deepscratches and other damage. If slight, theymay be removed carefully with a file, but ifexcessive, machining may be the onlyalternative to renewal.23 If warpage of the cylinder head gasketsurface is suspected, use a straight-edge tocheck it for distortion. Refer to Part D of thisChapter if necessary.24 Clean the threads of the cylinder headbolts or fit new ones (as applicable) and cleanout the bolt holes in the block. Screwing a boltinto an oil-filled hole can (in extreme cases)cause the block to fracture, due to thehydraulic pressure.Refitting25 Check that the new cylinder head gasketis the same type as the original, and that the“TOP” (or “OBEN”) marking is facingupwards. Locate the new cylinder head2A1595Ford Fiesta Remake

1595Ford Fiesta Remake2A•4 HCS engine in-car repair procedures4.6a Engage tags of rocker cover gasketinto the cut-outs in the coverRefitting5 Thoroughly clean the rocker cover, <strong>and</strong>scrape away any traces of old gasketremaining on the cover <strong>and</strong> cylinder headmating surfaces.6 Fit a new gasket to the rocker cover, thenrefit the rocker cover (see illustrations).Tighten the cover retaining bolts to thespecified torque wrench setting, in a diagonalsequence.7 Reconnect the HT leads, <strong>and</strong> refit the aircleaner as described in <strong>Chapter</strong> 4.5 Valve clearances -checking <strong>and</strong> adjustment2Note: The valve clearances must be checked<strong>and</strong> adjusted only when the engine is cold.1 The importance of having the valveclearances correctly adjusted cannot beoverstressed, as they vitally affect theperformance of the engine. If the clearancesare too big, the engine will be noisy(characteristic rattling or tapping noises) <strong>and</strong>engine efficiency will be reduced, as thevalves open too late <strong>and</strong> close too early. Amore serious problem arises if the clearancesare too small, however. If this is the case, thevalves may not close fully when the engine ishot, resulting in serious damage to the engine(eg. burnt valve seats <strong>and</strong>/or cylinder headwarping/cracking). The clearances arechecked <strong>and</strong> adjusted as follows.2 Set the engine to TDC for No 1 piston, asdescribed in Section 3.3 Remove the rocker cover as described inSection 4.4 Starting from the thermostat end of thecylinder head, the valves are numbered asfollows:Valve NoCylinder No1 - Exhaust 12 - Inlet 13 - Exhaust 24 - Inlet 25 - Inlet 36 - Exhaust 37 - Inlet 48 - Exhaust 44.6b Refitting the rocker cover5 Adjust the valve clearances following thesequence given in the following table. Turnthe crankshaft pulley 180º (half a turn) afteradjusting each pair of valve clearances.Turning the engine will beeasier if the spark plugs areremoved first - see <strong>Chapter</strong> 1.Valves “rocking” Valves to adjust7 <strong>and</strong> 8 1 (exhaust), 2 (inlet)5 <strong>and</strong> 6 3 (exhaust), 4 (inlet)1 <strong>and</strong> 2 8 (exhaust), 7 (inlet)3 <strong>and</strong> 4 6 (exhaust), 5 (inlet)6 The clearances for the inlet <strong>and</strong> exhaustvalves differ (refer to the Specifications). Use afeeler gauge of the appropriate thickness tocheck each clearance between the end of thevalve stem <strong>and</strong> the rocker arm (seeillustration). The gauge should be a firmsliding fit between the valve <strong>and</strong> rocker arm.Where adjustment is necessary, turn theadjuster bolt as required with a ring spannerto set the clearance to that specified. Theadjuster bolts are of stiff-thread type, <strong>and</strong>require no locking nut.7 On completion, refit the rocker cover asdescribed in Section 4.6 Cylinder head rocker gear -removal, inspection <strong>and</strong> 2refittingRemoval1 Remove the rocker cover as described inSection 4.2 Unscrew the four retaining bolts, <strong>and</strong> lift therocker gear assembly from the cylinder head.As the assembly is withdrawn, ensure that thepushrods remain seated in their positions inthe engine.Inspection3 To dismantle the rocker shaft assembly,extract the split pin from one end of the shaft,then withdraw the spring <strong>and</strong> plain washersfrom the shaft.4 Slide off the rocker arms, the supportpedestals <strong>and</strong> coil springs from the shaft, but5.6 Adjusting the valve clearancesIf the pushrods are to be removed,keep them in the correct order of fittingby labelling them 1 to 8, starting fromthe thermostat end of the cylinderhead, or locate them in a card.take care to keep them in their original orderof fitting (see illustration).5 Clean the respective components, <strong>and</strong>inspect them for signs of excessive wear ordamage. Check that the oil lubrication holes inthe shaft are clear.6 Check the rocker shaft <strong>and</strong> arm pads whichbear on the valve stem end faces for wear <strong>and</strong>scoring, <strong>and</strong> check each rocker arm on theshaft for excessive wear. Renew anycomponents as necessary.Refitting7 Apply clean engine oil to the rocker shaftprior to reassembling.6.4 Rocker shaft partially dismantled forinspection

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