Fiat Uno Manual
Engine - 1372 cc ie and 1372 cc Turbo ieSupplement: Revisions and information on later models / Engine - 1372 cc ie and 1372 cc Turbo ie
PART A: GENERAL
1 The 1372 cc engine is similar in design to the OHC engine fitted to the FIAT Tipo variants. The engine is of four-cylinder, in-line, overhead camshaft type, mounted transversely at the front of the vehicle.
2 The crankshaft runs in five main bearings.
Thrustwashers are fitted to the rear (flywheel end) main bearing in order to control crankshaft endfloat.
3 The connecting rods are attached to the crankshaft by horizontally split shell-type big-end bearings. The pistons are attached to the connecting rods by fully-floating gudgeon pins which are secured by circlips. The aluminium alloy pistons are fitted with three piston rings: two compression rings and an oil control ring.
4 The camshaft is driven by a toothed belt and operates the valves via bucket and shim type cam followers. The camshaft is located in a separate housing on top of the cylinder head.
5 The inlet and exhaust valves are each closed by double valve springs, and operate in guides pressed into the cylinder head.
6 The auxiliary shaft, which is also driven by the toothed belt, drives the oil pump.
7 Lubrication is by means of a gear type pump which draws oil through a strainer located in the sump, and forces it through a full-flow filter into the engine oil galleries from where it is distributed to the crankshaft, camshaft and auxiliary shaft. The big-end bearings are supplied with oil via internal drillings in the crankshaft. The undersides of the pistons are cooled by oil spray nozzles located in each main bearing location in the crankcase.
8 A crankcase ventilation system is employed, whereby piston blow-by gases are drawn via an oil separator into the air cleaner, from where they are drawn into the inlet manifold and re-burnt with fresh air/fuel mixture.
9 The 1372 cc ie engine is fitted with a Bosch Mono-Jetronic single point fuel injection (SPi) system. Whilst the higher performance 1372 cc Turbo ie engine is fitted with a Bosch L3.1 (L3.2 from 1992) Jetronic multi-point injection (MPi) system and turbocharger with intercooler and oil cooling. The L3.2 system models are fitted with catalytic converters.
10 At the intervals specified in Section 3 or “Routine maintenance” at the beginning of this Manual, carry out the following tasks.
11 Check the engine oil level as follows. With the vehicle parked on level ground, and with the engine having been stopped for a few minutes, withdraw the oil level dipstick, wipe it on a clean rag, and re-insert it fully. Withdraw the dipstick again and read off the oil level relative to the MAX and MIN marks. The oil level should be between the marks. If the level is at or below the MIN mark, top up through the filler on the camshaft cover without delay (photo). The quantity of oil required to raise the level from MIN to MAX on the dipstick is approximately 1.0 litre (1.8 pints). Do not overfill.
7A.11 Topping up the engine oil level - 1372 cc engine
12 Renew the engine oil and filter as described in Section 2 of Chapter 1 (photos).
7A.12A Engine sump drain plug - 1372 cc engine
7A.12B Engine oil filter removal using a strap wrench - 1372 cc engine
13 Check and if necessary adjust the valve clearances as described in Part B of this Section.
14 Inspect the engine for signs of oil, coolant or fuel leaks and rectify as necessary.
15 Inspect the crankcase ventilation hose for blockage or damage. Clean or renew as necessary.
16 Check the condition and tension of the timing belt as described in Part B of this Section.
17 Renew the timing belt as described in Part B of this Section.
Fig. 13.15 Engine oil level dipstick location and level markings on the 1372 cc ie and Turbo ie engines (Sec 7A)
WITH ENGINE IN CAR
Valve clearances -
checking and adjustment
1 It is important to ensure that the valve clearances are set correctly, as incorrect clearances will result in incorrect valve timing thus affecting engine performance.
2 The clearances must be checked and adjusted with the engine cold.
3 On the ie engine, refer to Section 9 in this Chapter for details and remove the air cleaner unit.
4 On the ie engine disconnect the crankcase ventilation hose from the injector unit and position the hose out of the way.
5 On Turbo ie engines, loosen off the clips and remove the air hose to the inlet manifold (above the camshaft cover).
6 On Turbo ie engines, disconnect the accelerator cable from the throttle housing and the support bracket on the camshaft cover.
7 Unscrew the securing nuts and washers and remove the camshaft cover, noting that on later models two of the nuts also secure the hose clip assembly. Recover the gasket.
8 Numbering from the front (timing belt) end of the engine, the exhaust valves are 1, 4, 5 and 8, and the inlet valves are 2, 3, 6 and 7.
9 Turn the engine clockwise using a suitable socket on the crankshaft pulley bolt, until the exhaust valve of No 1 cylinder (valve No 1) is fully closed; ie the cam lobe is pointing directly upwards. Alternatively, the engine can be turned by jacking up one front corner of the vehicle and supporting it securely on an axle stand (apply the handbrake and chock the diagonally-opposite rear wheel before jacking), engaging top gear and turning the raised roadwheel in the forward direction of travel. In both cases, it will be easier to turn the engine if the spark plugs are removed, but if this is done, take care not to allow dirt or other foreign matter to enter the spark plug holes.
10 Insert a feeler gauge of the correct thickness between the cam follower shim and the heel of the No 1 cam lobe (photo). If necessary, increase or reduce the thickness of the feeler gauge until it is a firm sliding fit.
Record the thickness of the feeler gauge, which will represent the valve clearance for this particular valve.
7B.10 Measuring a valve clearance (No 2 valve shown)
11 Turn the crankshaft, and repeat the procedure for the remaining valves, recording their respective clearances. Note that the clearance for inlet and exhaust valves differs.
12 If a clearance is incorrect, the relevant cam follower shim must be removed, and a thicker or thinner shim must be fitted to achieve the correct clearance. To remove a shim proceed as follows.
13 Turn the crankshaft until the relevant cam lobe is pointing directly upwards.
14 The cam follower must now be depressed in order to extract the shim. FIAT special tool No 1860642000 is available for this purpose, but alternatively a suitable tool can be improvised (photo). The tool should locate on the rim of the cam follower, leaving enough room for the shim to be prised out by means of the cut-outs provided in the cam follower rim. Depress the cam follower by turning the crankshaft as described previously until the relevant cam lobe is pointing directly downwards, then fit the tool between the camshaft and the edge of the cam follower to retain the cam follower in the depressed position.
7B.14 Special tool for retaining cam follower in depressed position
15 Ensure that the tool is securely located, as there is a risk of personal injury if the tool is dislodged whilst the cam follower is depressed, then turn the crankshaft until the relevant cam lobe is pointing directly upwards, leaving sufficient room to extract the shim (photo). A pair of angle-nosed pliers will greatly ease removal of the shim.
7B.15 Removing a shim from a cam follower
16 Once the shim has been extracted, establish its thickness. The thickness in mm should be stamped into the face of the shim, although it is possible for wear to obliterate the number, in which case the use of a metric micrometer is the only way to accurately establish the thickness.
17 Refer to the clearance recorded for the
valve concerned. If the clearance recorded
was larger than that specified, a thicker shim
must be fitted, and if the clearance recorded
was smaller than that specified, a thinner shim
must be fitted. The required thickness of shim
calculated as follows.
Sample calculation - clearance too large:
Desired clearance (A) 0.40 mm
Measured clearance (B) 0.45 mm
Difference (B - A) + 0.05 mm
Original shim thickness 3.40 mm
Required shim thickness 3.40 + 0.05 =
Sample calculation - clearance too small: Desired clearance (A) 0.50 mm Measured clearance (B) 0.35 mm Difference (B - A) 0.15 mm Original shim thickness 4.55 mm Required shim thickness 4.55 - 0.15 = 4.40 mm
18 Shims are available in thicknesses from 3.20 to 4.70 mm, in steps of 0.05 mm. Note that if several shims have to be changed, they can often be interchanged, thus avoiding the need by buy more new shims than are necessary.
19 The shims should be fitted to the cam followers with the stamped thickness marking against the face of the cam follower.
20 After fitting a shim, rotate the crankshaft as described previously until the relevant cam lobe is pointing directly downwards (resting on the shim), then carefully remove the tool used to retain the follower in the depressed position.
21 Re-check each relevant valve clearance after fitting the shim.
22 On completion, where applicable, lower the vehicle to the ground.
23 Refit the camshaft cover, using a new gasket.
24 On the ie engine, reconnect the hoses and refit the air cleaner unit.
25 On the Turbo ie engine, reconnect the air hose and the accelerator cable.
Timing belt tensioner
and sprockets -
removal and refitting
Note: The timing belt must be renewed after removal: never refit a used drivebelt. When fitting the new timing belt it will need to be correctly tensioned and to achieve this the manufacturers specify the use of special tools 1860745200 (18760745300 on Turbo model) and 1860745100. If these tools are not readily available, an approximate setting can be made, but in this instance it is strongly recommended that the car be taken to a FIAT dealer at the earliest opportunity to have the belt tension checked and correctly set using the recommended tools.
26 Loosen off the front right-hand side wheel bolts, then raise and support the car at the front end on axle stands. Remove the front right-hand roadwheel.
27 Remove the underwing shield from the right-hand wheel arch to allow access to the lower timing cover and alternator fixings (photo).
7B.27 Underwing shield (A) showing central compression pin (B) and retaining clip (C). Drive pin through clip to remove
28 Loosen off the retaining clips and detach the air intake pipe from the air filter.
29 Slide back the inspection cover from the upper end of the timing cover (photo).
7B.29 Slide back inspection cover in the timing case
30 Turn the engine over by hand to bring the TDC timing marks of the flywheelto- bellhousing and the camshaft sprocket -to-rear cover projection into alignment. The crankshaft pulley also has a TDC timing mark and this should be positioned as shown (photos).
7B.30A Camshaft sprocket timing notch aligned with timing (TDC) pointer in timing case
7B.30B Crankshaft pulley and timing cover timing marks
31 Loosen off the retaining and adjustment strap fixings, then pivot the alternator towards the engine.
32 Unscrew the upper retaining bolts securing the timing cover.
33 Loosen off the nut securing the alternator and its drivebelt relay, then detach and remove the alternator drivebelt.
34 Unscrew and remove the crankshaft pulley nut. Where the engine is in the car, prevent the crankshaft from turning by engaging top gear and having an assistant apply the brake pedal hard. Unscrew and remove the flywheel housing lower cover bolts and remove the cover. The flywheel ring gear can now be jammed with a suitable lever or implement to prevent the crankshaft from rotating. It should be noted that the pulley nut is tightened to a considerable torque and a strong socket, together with an L-bar and extension tube, will therefore be required to loosen and remove it (photo). Take care not to damage the gearbox/flywheel housing by jamming the flywheel at a weak point.
7B.34 Crankshaft pulley nut removal
35 Withdraw the crankshaft pulley (photo).
7B.35 Crankshaft pulley removal
36 Unscrew and remove the lower retaining bolts and remove the timing cover upwards from the vehicle.
37 Check that the previously mentioned timing marks are still in alignment. Loosen off the timing belt tensioner nut, then with the tension released, withdraw the timing belt from the sprockets.
38 To remove the drivebelt tensioner, undo the securing nut and withdraw the tensioner pulley unit noting that it is in three sections (photos).
7B.38A Timing belt tensioner removal
7B.38B The three sections of the timing belt tensioner
39 If desired, the sprockets and the rear timing belt cover can be removed as follows, otherwise proceed to paragraph 49.
40 To remove the camshaft sprocket, a suitable tool must be used to hold the camshaft stationary as the sprocket bolt is loosened. A suitable tool can be improvised as shown in photo 7B.48 using two pieces of steel bar joined together by a pivot bolt, with suitable bolts through the ends of the steel bars to engage with the holes in the sprocket.
41 Unscrew the sprocket bolt, then recover the plain washer, and the thrust washer which is bonded into a plastic sleeve (photo).
7B.41 Removing the crankshaft sprocket bolt, plain washer and thrust washer
42 The sprocket can now be withdrawn from the end of the camshaft. If the sprocket is tight, carefully lever it from the camshaft using two screwdrivers, but take care not to damage the rear timing belt cover.
43 The crankshaft sprocket can be removed by simply pulling it from the end of the crankshaft after the pulley securing nut has been removed. Recover the Woodruff key from the end of the crankshaft if it is loose (photo).
7B.43 Remove the crankshaft Woodruff key if it is loose
44 To remove the auxiliary shaft sprocket, a suitable tool must be used to hold the sprocket stationary as the securing bolt is loosened (the bolt is extremely tight). In the workshop, a “scissors” style tool was improvised, using two pieces of steel bar joined together by a pivot bolt, with their ends bent through a right-angle to engage securely between the teeth on the sprocket - see photo 7B.46.
45 Unscrew the sprocket bolt, and recover the washer, then withdraw the sprocket from the end of the auxiliary shaft (photo). If the sprocket is tight, carefully lever it from the shaft using two screwdrivers.
7B.45 Withdrawing the auxiliary shaft sprocket
46 Refit the auxiliary shaft sprocket, making sure that the lug on the end of the shaft engages with the hole in the sprocket, then tighten the securing bolt to the specified torque (ensure that the washer is in place under the bolt head). Prevent the sprocket from turning as during removal (photo).
7B.46 Tightening the auxiliary shaft sprocket bolt
47 Where applicable, refit the Woodruff key to the end of the crankshaft, then refit the crankshaft sprocket with the flanged side against the oil seal housing (photo).
7B.47 Refitting the crankshaft sprocket
48 Refit the camshaft sprocket to the end of the camshaft, making sure that the lug on the end of the shaft engages with the hole in the sprocket, then refit the thrust washer, plain washer, and bolt, and tighten the bolt to the specified torque. Prevent the camshaft from turning as during removal (photo).
7B.48 Tightening the crankshaft sprocket bolt
49 Refit the belt tensioner pulley assembly, ensuring that the washer is in place under the securing nut, but do not fully tighten the nut at this stage.
50 Before refitting the new timing belt into position, first ensure that the crankshaft and camshaft sprocket timing marks are still aligned as described in paragraph 30 (photo).
7B.50 Crankshaft at TDC with key and timing mark aligned (arrowed)
51 If the new timing belt has two timing marks on its outer face they must align with the corresponding marks on the crankshaft and camshaft sprockets. Do not distort or bend the belt any more than is necessary during its fitting or its structural fibres may be damaged.
52 Refit the belt around the sprockets and the tensioner pulley, starting at the crankshaft sprocket. One of the timing index marks must align with the scribed mark on the lower edge of the crankshaft sprocket (opposite the Woodruff key) whilst the second mark must align with the timing marks of the camshaft and rear timing belt cover (photos).
7B.52A Timing belt refitted over the sprockets and tensioner
7B.52B Timing belt mark aligned with scribed mark on crankshaft sprocket (arrowed)
53 With the belt fitted over the sprockets and correctly aligned, temporarily refit the crankshaft pulley nut (tightening it to its full torque wrench setting) and then adjust the timing belt tension.
54 The timing belt tension can be checked approximately by twisting it between the thumb and forefinger at the centre of the run between the auxiliary shaft sprocket and the camshaft sprocket. Using this method it should just be possible to twist the belt through 90º using moderate pressure.
55 To adjust the tension, loosen off the tensioner pulley nut then insert two rods (or screwdrivers) into position in the pulley holes and position a lever between them.
56 Gently lever the tensioner pulley in the required direction to set the tension as described, then initially tighten the pulley nut to lock the tensioner in the required position.
57 Remove the tools from the tensioner, recheck the tension and then tighten the tensioner pulley nut securely.
58 Rotate the crankshaft clockwise through two complete turns using a socket or spanner on the crankshaft pulley nut, then recheck the belt tension. To avoid the possibility of unscrewing the pulley nut, remove the spark plugs to enable the engine to be turned over easier.
59 If further adjustment is required, repeat the previously mentioned procedures. If in doubt, err on the slightly tight side when adjusting the tension. If the belt is set too loose, it may jump off the sprockets resulting in serious damage.
60 Remove the crankshaft pulley retaining nut, fit the timing belt cover, then refit and tighten the pulley nut to the specified torque setting.
61 Refit the remaining components in the reverse order of removal. Tighten the retaining nuts/bolts to the specified torque settings where given. Adjust the tension of the alternator drivebelt as described in Section 8.
Adjustment using FIAT special
62 Assemble the special tools and fit them to the belt tensioner pulley as shown in Fig. 13.16. When fitted, the tool rod must be as vertical as possible and it is important to note that no sliding weights must be attached to tool No. 1860745100.
63 Slacken the tensioner pulley nut, if not already done. Rotate the crankshaft clockwise through two complete turns using a socket or spanner on the crankshaft pulley nut. The special tool rod may move from the vertical as the engine is turned over, in which case the joint will need to be re-adjusted to return the rod to the vertical and the operation repeated.
64 With the two revolutions of the crankshaft completed, tighten the belt tensioner pulley nut securely and remove the special tools.
65 Remove the crankshaft pulley retaining nut, fit the timing belt cover, then refit and tighten the pulley nut to its specified torque setting.
66 Refit the remaining components in the reverse order of removal. Tighten the retaining nuts/bolts to the specified torque settings where given. Adjust the tension of the alternator drivebelt as described in Section 8.
Camshaft front oil seal -
67 The camshaft front oil seal may be renewed with the engine in the vehicle, and the camshaft in situ, as follows.
68 Remove the timing belt and the camshaft sprocket as described previously in this Section.
69 Punch or drill a small hole in the centre of the exposed oil seal. Screw in a self-tapping screw, and pull on the screw with pliers to extract the seal.
70 Clean the oil seal seat with a wooden or plastic scraper.
71 Lubricate the lips of the new seal with clean engine oil, and drive it into position until it is flush with the housing, using a suitable socket or tube. Take care not to damage the seal lips during fitting. Note that the seal lips should face inwards.
72 Refit the camshaft sprocket and the timing belt as described previously in this Section.
Camshaft, housing and
removal and refitting
Note: The engine must be cold when removing the camshaft housing. Do not remove the camshaft housing from a hot engine. New camshaft housing and camshaft cover gaskets must be used on refitting.
73 If the engine is still in the vehicle, disconnect the battery negative lead.
74 Refer to paragraphs 3 to 7 in this part of this Section for details and remove the camshaft cover.
75 Remove the camshaft sprocket and timing belt as described previously in this Section.
76 Remove the three securing nuts and the single securing bolt, and withdraw the upper section of the rear timing belt cover.
77 Unscrew the camshaft housing securing bolts. There are seven bolts which are accessible from outside the camshaft housing, and five shorter bolts which are accessible from inside the housing (these bolts are normally covered by the camshaft cover). Note that each bolt is fitted with two washers (photo).
7B.77 Removing one of the camshaft housing shorter securing bolts
78 Carefully lift the camshaft housing from the cylinder head. Be prepared for the cam followers to drop from their bores in the camshaft housing as the camshaft housing is lifted, and ensure that the cam followers are identified for position so that they can be refitted in their original positions (this can be achieved by placing each cam follower over its relevant valve in the cylinder head).
79 Recover the gasket.
80 Removal of the camshaft from the housing, and inspection of the components is described in the following sub-Section.
81 Commence refitting by cleaning the gasket mating surfaces of the camshaft housing and cylinder head.
82 Locate a new gasket on the cylinder head, making sure that it is correctly positioned over the dowels (photo).
7B.82 Locating a new camshaft housing gasket on the cylinder head
83 Ensure that the cam followers are correctly located over their relevant valves.
84 Liberally oil the cam follower bores in the camshaft housing, then carefully lower the housing over the cam followers, and onto the cylinder head (photo). Some manipulation will be required to engage the cam followers with their relevant bores in the camshaft housing.
7B.84 Lowering the camshaft housing on to the cylinder head
85 Loosely refit all the camshaft housing securing bolts, ensuring that the washers are in place under their heads, then tighten them progressively to the specified torque, starting at the centre of the housing and working outwards in a spiral pattern (photo).
7B.85 Tightening a camshaft housing securing bolt
86 Refit the upper section of the rear timing belt cover.
87 Refit the camshaft sprocket and the timing belt as described previously in this Section.
88 Check the valve clearances as described earlier in this Section.
89 Refit the camshaft cover using a new gasket, and tighten the securing nuts, ensuring that the washers are in place (photos). Where applicable, ensure that the hose clip is in place before refitting the relevant camshaft cover securing nuts.
7B.89A Locate a new gasket on the camshaft housing . . .
7B.89B . . . and refit the camshaft cover
90 The remainder of the refitting procedure is a reversal of that given for removal.
Camshaft, housing and followers
- dismantling, inspection
91 With the camshaft housing removed from the cylinder head as previously described proceed as follows.
92 Unscrew the three securing bolts, and withdraw the blanking plate from the end of the camshaft housing. Recover the gasket.
93 The camshaft can now be carefully withdrawn from the blanking plate/distributor end of the camshaft housing, taking care not to damage the bearing journals (photo).
7B.93 Withdrawing the camshaft from its housing
94 With the camshaft removed, examine the bearings in the camshaft housing, and the cam follower bores for signs of obvious wear or pitting. If evident, a new camshaft housing will probably be required.
95 The camshaft itself should show no signs of marks or scoring on the journal or cam lobe surfaces. If evident, renew the camshaft.
96 Examine the cam followers for signs of obvious wear, and for ovality, and renew if necessary.
97 It is advisable to renew the camshaft front oil seal as a matter of course if the camshaft has been removed. Prise out the old seal using a screwdriver, and drive in the new seal until it is flush with the housing, using a suitable socket or tube (photos).
7B.97A Prising out the camshaft front oil seal
7B.97B Inserting the new camshaft front oil seal
98 Commence reassembly by liberally oiling the bearings in the housing, and the oil seal lip.
99 Carefully insert the camshaft into the housing from the blanking plate/distributor end, taking care to avoid damage to the bearings.
100 Refit the blanking plate using a new gasket.
101 Refit the camshaft housing as described previously in this Section.
(1372 cc ie engine) -
removal and refitting
Note: The following instructions describe cylinder head removal and refitting leaving the camshaft, manifolds and associated items in situ In the head. If required, these items can be removed separately. When removing the cylinder head the engine must be cold - do not remove the head from a hot engine. A new cylinder head gasket and any associated gaskets must be used during reassembly. FIAT specify that the main cylinder head bolts should be renewed after they have been used (ie tightened) four times. If in any doubt as to the number of times that they have been used renew them as a precaution against possible failure.
Warning: Refer to the beginning of Section 9 before starting any work.
102 Depressurise the fuel supply system as described in Section 9 of this Chapter.
103 Disconnect the battery negative lead.
104 Drain the engine coolant as described in Section 8.
105 Remove the air cleaner unit as described in Section 9.
106 Remove the timing belt as described previously in this Section.
107 Disconnect the crankcase ventilation hose from the cylinder head and the SPi injector unit.
108 Disconnect the accelerator cable at the engine end.
109 Detach the engine idle speed check actuator lead, the inlet manifold vacuum sensor lead, the coolant temperature sensor lead, the injector supply lead, the throttle position switch lead and the distributor cap (with HT leads). Position them out of the way.
110 Disconnect the brake servo hose from the manifold.
111 Disconnect the coolant hoses from the thermostat and the inlet manifold.
112 Slowly release the fuel supply and return hose retaining clips and detach the hoses from the injector unit housing and connections. Catch any fuel spillage in a clean cloth and plug the hoses to prevent the ingress of dirt and further fuel loss.
113 Unbolt and detach the exhaust downpipe from the manifold.
114 Loosen off the cylinder head retaining bolts in a progressive manner, reversing the sequence shown in Fig. 13.17. When all of the bolts are loosened off, extract them and collect the washers.
115 Check that all fittings and associated attachments are clear of the cylinder head, then carefully lift the head from the cylinder block. If necessary tap the head lightly with a soft-faced mallet to free it from the block, but do not lever it free between the joint faces.
Note that the cylinder head is located on dowels.
116 Recover the old cylinder head gasket and discard it.
117 Clean the cylinder head and block mating surfaces by careful scraping. Take care not to damage the cylinder head - it is manufactured in light alloy and is easily scored. Cover the coolant passages and other openings to prevent dirt and carbon from falling into them. Mop out all the oil from the cylinder head bolt holes - if oil is left in them, hydraulic pressure, caused when the bolts are refitted, could cause the block to crack.
118 If required the cylinder head can be dismantled and overhauled as described in paragraphs 129 to 131 of this Section.
119 The new gasket must be removed from its protective packing just before it is fitted.
Do not allow any oil or grease to come into contact with the gasket. Commence refitting the cylinder head by locating the new gasket on the cylinder block so that the word “ALTO” is facing up (photo).
7B.119 Locating a new cylinder head gasket on the cylinder block (engine shown on dismantling stand)
120 With the mating faces scrupulously clean, refit the cylinder head into position and engage it over the dowels. Refer to the note at the beginning of this part of the Section, then refit the ten main cylinder head bolts and washers. Screw each bolt in as far as possible by hand to start with. Do not fit the smaller (M8 x 1.25) bolts at this stage (photos).
7B.120A Lower the cylinder head onto the block . . .
7B.120B . . . and engage the positioning dowels in their holes
121 The bolts must now be tightened in stages and in the sequence shown in Fig. 13.17. Refer to the specified torque wrench settings and tighten all bolts to the Stage 1 torque, then using a suitable angle gauge, tighten them to the second stage, then the third stage (photos).
7B.121A Tighten main cylinder head bolts to specified torque . . .
7B.121B . . . and then through the specified angle
122 With the main cylinder head bolts fully tightened, refit the five smaller (M8 x 1.25) bolts adjacent to the line of the spark plug holes and tighten them to their specified torque wrench setting (photo).
7B.122 Tighten the smaller cylinder head bolts to their specified torque setting
123 Reconnect the associated fittings to the cylinder head in the reverse order of removal.
Ensure that the mating faces of the exhaust manifold-to-downpipe are clean and fit a new gasket when reconnecting.
124 Ensure that all wiring connections are cleanly and securely made.
125 Top up the engine oil and coolant levels as required on completion.
(1372 cc Turbo ie engine) - removal and refitting
126 Proceed as described in paragraphs 102 to 125 above for the non-Turbo model, but note the following differences.
127 The cylinder head cannot be removed and refitted with the manifolds and turbocharger fitted. It is therefore first necessary to detach and remove the inlet manifold, then the turbocharger and the exhaust manifold as described in Section 9.
128 The ignition distributor is mounted on the side of the engine, not the rear end of the cylinder head as on the “ie” engine. It is therefore only necessary to disconnect the HT leads from the spark plugs.
Cylinder head - inspection
Note: Refer to a dealer for advice before attempting to carry out valve grinding or seat recutting operations. These operations may not be possible for the DIY mechanic due to the fitment of hardened valve seats for use with unleaded petrol.
129 Use a straight-edge to check the cylinder head gasket surface for distortion. If it exceeds the specified tolerance, it must be resurfaced by a FIAT dealer or automotive engineer.
130 Refer to Section 39 in Chapter 1 for the general details on dismantling and renovating operations on the cylinder head but note that there is a spring seat and a flat washer fitted between the cylinder head and the valve springs (photos).
7B.130A Inlet (A) and exhaust (B) valves and associate components - 1372 cc engine
7B.130B Valve assembly - 1372 cc engine; insert valve into guide . . .
7B.130C . . . locate stem oil seal . . .
7B.130D . . . and drive it into position
7B.130E Refit the flat washer . . .
7B130F . . . locate the spring seat . . .
7B.130G . . . the inner spring . . .
7B.130H . . . the outer spring . . .
7B.130I . . . and cap
7B.130J Compress spring and refit the split collets
Crankshaft front oil seal -
removal and renewal
131 Remove the timing belt as described earlier in this Section. Note that as mentioned previously, the timing belt will need to be renewed during reassembly.
132 Referring to Fig. 13.18, loosen off the bolt indicated from the timing belt rear cover.
133 Drain the engine oil from the sump into a suitable container. Disconnect the lead from the engine oil level sensor in the sump.
134 Where applicable, unscrew and remove the bolts retaining the gear linkage mounting bracket and the clutch housing lower cover bolts. Remove the cover from the clutch housing.
135 Unscrew the sump retaining nuts and bolts, then lower and remove the sump.
136 Unscrew the timing belt rear cover retaining bolts.
137 Move the timing belt rear cover towards the front of the car to gain access to the retaining bolt and then unscrew and remove the three oil seal housing retaining bolts.
Remove the crankshaft front oil seal housing.
138 Note the orientation of the seal in its housing prior to its removal. Support the underside of the housing and carefully drive the old oil seal from the housing using a punch or a tubular drift of suitable diameter.
An alternative method is to punch or drill a small hole in the face of the oil seal (but take care not to drill into the housing) and insert a self-tapping screw into the seal. Withdraw the seal by gripping the screw with pliers and pulling the seal from the housing. If necessary, fit a second screw into the seal on the opposite side to provide an even pull.
139 Clean the mating faces of the housing and the front of the crankcase using a suitable scraper.
140 Drive or press the new seal into position in the housing in the reverse order of removal, but ensure that it is correctly orientated as noted during removal (photo).
7B.140 Driving a new crankshaft front oil seal into its housing
141 Refit the oil seal housing with a new gasket and tighten the retaining bolts to the specified torque setting (photos).
7B.141A Refit the crankshaft front oil seal housing . . .
7B.141B . . . ensuring it is flush with the face of the cylinder block
142 Refit the sump as described later in this Section using a new gasket. Tighten its retaining nuts and bolts to the specified torque. Refit the clutch cover and the gear linkage mounting bracket.
143 Fit the new timing belt, adjust its tension and refit the crankshaft pulley as described earlier in this Section.
144 Reconnect the remaining components that were detached during removal in the reverse order and top up the engine oil level to complete.
Crankshaft rear oil seal -
removal and renewal
145 If the engine is still in the car, disconnect the battery negative lead.
146 Remove the flywheel as described in the next sub-Section.
147 Punch or drill a small hole in the rear face of the rear oil seal (but take care not to drill into the housing) and insert a self-tapping screw into the seal. Withdraw the seal by gripping the screw with pliers and pulling it from the housing. If necessary, fit a second screw into the seal on the opposite side to provide an even pull.
148 Clean the seal housing, then locate the new oil seal, ensuring that it is correctly orientated, and drive it squarely into position.
149 Refit all disturbed components.
Flywheel - removal,
inspection and refitting 150 If not already done, remove the clutch as described in Chapter 5.
151 Prevent the flywheel from turning by jamming the ring gear teeth, or by bolting a strap between the flywheel and the cylinder block.
152 Make alignment marks on the flywheel and the end of the crankshaft, so that the flywheel can be refitted in its original position.
153 Unscrew the securing bolts and remove the washer plate, then withdraw the flywheel.
Do not drop it, it is very heavy.
154 With the flywheel removed, the ring gear can be examined for wear and damage.
155 If the ring gear is badly worn or has missing teeth it should be renewed. The old ring gear can be removed from the flywheel by cutting a notch between two teeth with a hacksaw and then splitting it with a cold chisel. Wear eye protection when doing this.
156 Fitting of a new ring gear requires heating the ring to a temperature of 80ºC (176ºF). Do not overheat, or the hard-wearing properties will be lost. The gear has a chamfered inner edge which should fit against the shoulder on the flywheel. When hot enough, place the gear in position quickly, tapping it home if necessary, and let it cool naturally without quenching in any way.
157 Ensure that the mating faces are clean, then locate the flywheel on the rear of the crankshaft, aligning the previously made marks on the flywheel and crankshaft.
158 Fit the washer plate, and insert the securing bolts, then prevent the flywheel from turning as described in paragraph 151 whilst the bolts are tightened progressively to the specified torque setting in a diagonal sequence (photos).
7B.158A Locate the flywheel, washer plate and bolts . . .
7B.158B . . . tighten the bolts to the specified torque
159 If applicable, refit the clutch as described in Chapter 5.
removal and refitting
160 Drain the engine oil from the sump as described in Chapter 1.
161 Disconnect the lead from the engine oil level sensor in the sump.
162 Unscrew and remove the bolts retaining the gear linkage mounting bracket (where applicable) and the clutch housing lower cover bolts.
Remove the cover from the clutch housing.
163 Unscrew and remove the sump retaining bolts and nuts and lower the sump from the crankcase. Recover the gasket.
164 Clean all traces of old gasket from the sump, crankcase and both oil seal housing mating surfaces.
165 Commence reassembly by applying sealing compound (FIAT No. 5882442 or equivalent) to the joints between the crankshaft front and rear oil seal housings and the mating face of the crankcase (photo).
7B.165 Apply sealant to the front oil seal housing/cylinder block joint
166 Locate the new gasket in position on the crankcase then fit the sump. As it is fitted it will need to be twisted to avoid fouling the oil pump unit. Refit the retaining bolts and nuts and tighten them to the specified torque (photos).
7B.166A Locate the new gasket . . .
7B.166B . . . refit the sump . . .
7B.166C . . . and insert the retaining bolts
167 Check that the sump drain plug is refitted and fully tightened. If the engine is in the car, top up the engine oil level.
Oil pump - removal,
checking and refitting
168 Drain the engine oil and remove the sump as described in the previous sub-Section.
169 Unscrew the retaining bolts then withdraw the oil pump and intake pipe/filter from its location within the crankcase.
Remove the gasket.
170 If oil pump wear is suspected, first check the cost and availability of new parts and the cost of a new pump. Then examine the pump as described below and decide whether renewal or repair is the best course of action.
171 Unscrew the three securing bolts and remove the oil pump cover (photo). Note that as the cover is removed, the oil pressure relief valve components will be released.
7B.171 Undo the oil pump cover bolts
172 Recover the oil pressure relief valve, spring and spring seat.
173 Lift the intermediate plate from the oil pump body.
174 The gears can now be removed from the oil pump body. Inspect them for obvious signs of wear or damage, and renew if necessary.
175 Commence reassembly by lubricating the gears with clean engine oil, and refitting them to the casing. Note that the scribed marks on the top faces of the gears should face each other with the gears installed (photo).
7B.175 Correct alignment of scribed marks (arrowed) on gears
176 Using a feeler gauge, check that the clearance between the gears and the pump body is within the limits given in the Specifications (photo).
7B.176 Check gear-to-body clearance
177 Using a straight-edge placed across the top of the pump body and the gears, and a feeler gauge, check that the gear endfloat is within the limits given in the Specifications (photo).
7B.177 Checking the gear endfloat
178 If either the gear-to-body clearance, or the gear endfloat is outside the specified limits, both gears should be renewed.
179 Locate the intermediate plate on the pump body (photo).
7B.179 Refitting the intermediate plate
180 Place the pressure relief valve and spring over the pressure relief hole in the intermediate plate, and locate the spring seat over the boss in the pump cover, then refit the pump cover, ensuring that the pressure relief valve components seat correctly (photos).
7B.180A Locate pressure relief valve and spring on the intermediate plate
7B.180B Locate spring seat over boss within pump cover . . .
7B.180C . . . then fit the cover
181 Refit and tighten the pump cover securing bolts.
182 Thoroughly clean the mating faces of the pump and crankcase before refitting the pump. Prime the pump by injecting clean engine oil into it and turning it by hand.
183 Fit the pump using a new gasket, then insert the securing bolts and tighten them.
184 Refit the sump and top up the engine oil level.
Pistons/connecting rods -
removal and refitting
185 Remove the sump and the cylinder head as described previously in this Section.
186 The big-end caps and connecting rods normally have identification marks stamped into their sides, facing the coolant pump side of the cylinder block. If no marks are present, use a centre-punch to identify the bearing caps and the connecting rods for location.
187 Turn the crankshaft so that No. 1 crankpin is at its lowest point, then unscrew the nuts and tap off the bearing cap. Keep the bearing shells in the cap and the connecting rod if they are to be re-used, taping them in position if necessary to avoid loss.
188 Using the handle of a hammer, push the piston and connecting rod up the bore and withdraw it from the top of the cylinder block.
Loosely refit the cap to the connecting rod.
189 Repeat the procedure given in paragraphs 187 and 188 on No. 4 piston and connecting rod, then turn the crankshaft through half a turn and repeat the procedure on Nos 2 and 3 pistons and connecting rods.
190 The pistons and connecting rods and the big-end bearings can be examined and if necessary renovated as described later in this Section.
191 Commence refitting as follows.
192 Clean the backs of the bearing shells and the recesses in the connecting rods and big-end caps.
193 Lubricate the cylinder bores with engine oil.
194 Fit a ring compressor to No. 1 piston, then insert the piston and connecting rod into No. 1 cylinder. With No 1 crankpin at its lowest point, drive the piston carefully into the cylinder with the wooden handle of a hammer (photos).
Leave enough space between the connecting rod and the crankshaft to allow the bearing shell to be fitted. The piston must be fitted with the cut-out in the piston crown on the auxiliary shaft side of the engine, and the cylinder identification marking on the connecting rod and big-end cap on the coolant pump side of the engine - see Fig. 13.21.
7B.194A Fitting a ring compressor to a piston
7B.194B Tapping a piston into its bore
195 Slide the appropriate bearing shell into position in the connecting rod big-end, then pull the connecting rod firmly into position on the crankpin (photo).
7B.195 Assemble the shell bearing to the connecting rod . . .
196 Press the appropriate bearing shell into position in the big-end cap (photo).
7B.196 . . . and big-end bearing cap . . .
197 Oil the crankpin, then fit the big-end bearing cap with the cylinder identification marking on the coolant pump side of the engine, and tighten the nuts to the specified torque setting (photos).
7B.197A . . . then fit the cap . . .
7B.197B . . . and tighten the nuts to the specified torque
198 Check that the crankshaft turns freely.
199 Repeat the procedure in paragraphs 194 to 198 inclusive on the remaining pistons.
200 Refit the cylinder head and the sump.
Pistons/connecting rods -
201 The procedures for inspecting and renovating the pistons and connecting rod assemblies are in general the same as that described for the smaller engines in Section 18 of Chapter 1. However, the following additional points should be noted.
202 When renewing a gudgeon pin, first check the fit in the piston. It should be possible to fit the gudgeon pin using hand pressure, but the pin should be a tight enough fit that it does not drop out under its own weight. Oversize gudgeon pins are available as spares if necessary. Use new circlips when refitting the pistons to the connecting rods.
203 Before fitting the pistons to their connecting rods, weigh each piston and check that their weights are all within 2.5 g of each other. If not, the heavier pistons must be lightened by machining metal from the underside of the small-end bosses. This operation must be entrusted to a FIAT dealer or engine reconditioning specialist.
204 The pistons should be fitted to the connecting rods so that the higher, flat side of the piston crown is on the side of the connecting rod with the stamped cylinder identification number, ie the gudgeon pin is offset towards the cylinder identification number see Fig. 13.21.
205 The piston rings should be fitted with the word “TOP” on each ring facing uppermost, or if no marks are visible, as noted during removal. If a stepped top compression ring is being fitted, fit the ring with the smaller diameter of the step uppermost. The ring end gaps should be offset 120º from each other.
Use two or three old feeler gauges to assist fitting, as during removal. Note that the compression rings are brittle, and will snap if expanded too far.
206 If new pistons are to be fitted, they must be selected from the grades available, after measuring the cylinder bores. Normally, the appropriate oversize pistons are supplied by the dealer when the block is rebored.
207 Whenever new piston rings are being installed, the glaze on the original cylinder bores should be removed using either abrasive paper or a glaze-removing tool in an electric drill. If abrasive paper is used, use strokes at 60º to the bore centre-line, to create a cross-hatching effect.
mountings - renewal
208 The engine/gearbox assembly is suspended in the engine compartment on three mountings, two of which are attached to the gearbox, and one to the engine.
209 Apply the handbrake, then jack up the front of the vehicle and support it securely on axle stands.
210 Suitable lifting tackle must now be attached to the engine in order to support it as the engine mounting is removed. No lifting brackets are provided, so care must be taken when deciding on an engine lifting point. In the workshop, a right-angled bracket was made up by bending a suitable piece of steel plate. The bracket was then bolted to the engine using the rear right-hand camshaft housing securing bolt with suitable packing washers.
211 Attach the lifting tackle to the bracket on the engine and just take the weight of the assembly.
212 Working under the vehicle, unbolt the engine mounting bracket from the cylinder block, and unbolt the mounting from the body, then withdraw the bracket/mounting assembly.
213 Unscrew the nut and through-bolt, counter holding the bolt with a second spanner or socket, and separate the mounting from the bracket.
214 Fit the new mounting to the bracket, and tighten the nut to the specified torque, while counterholding the through-bolt using a suitable spanner or socket.
215 Refit the mounting bracket to the cylinder block, and tighten the securing bolts to the specified torque.
216 Refit the mounting to the body and tighten the securing bolts to the specified torque.
217 Disconnect the lifting tackle from the engine, and remove the engine lifting bracket.
218 Lower the vehicle to the ground.
219 Apply the handbrake, then jack up the front of the vehicle and support it securely on axle stands.
220 Suitable lifting tackle must now be attached to the gearbox lifting bracket in order to support the weight of the assembly as the mounting is removed.
221 Attach the lifting tackle to the bracket on the gearbox, and just take the weight of the assembly.
222 Working under the vehicle, unbolt the mounting bracket from the gearbox, and unbolt the mounting from the body, then withdraw the bracket/mounting assembly.
223 Proceed as described in paragraphs 213 and 214.
224 Refit the mounting bracket to the gearbox, and tighten the securing bolts to the specified torque.
225 Refit the mounting to the body and tighten the mounting bolts to the specified torque.
226 Disconnect the lifting tackle from the engine.
227 Lower the vehicle to the ground.
Fig. 13.16 FIAT special tool No. 1860745100 (A) for timing belt adjustment shown fitted to the tensioner pulley - 1372 cc ie and Turbo ie engines (Sec 7B)
Use with adapter No. 1860745200 on 1372 cc ie engines and No. 1860745300 on 1372 cc Turbo ie engines
Fig. 13.17 Cylinder head bolt tightening sequence on the 1372 cc ie and Turbo ie engines (Sec 7B)
Fig. 13.18 Timing belt rear cover bolt (arrowed) - 1372 cc ie and Turbo ie engines (Sec 7B)
Fig. 13.19 Unscrew the bolts at the points indicated to release the gear linkage mounting bracket - 1372 cc ie and Turbo ie engines (Sec 7B)
Fig. 13.20 Removing the timing belt rear cover on the 1372 ie and Turbo ie engines (Sec 7B)
Fig. 13.21 Correct orientation of piston and connecting rod in engine - 1372 cc ie and Turbo ie engines (Sec 7B)
1 Auxiliary shaft
2 Cylinder identification markings on connecting rod and big-end cap Arrow denotes direction of engine rotation Note offset gudgeon pin
PART C: ENGINE REMOVAL
Method of removal - general 1 The engine (complete with transmission) is disconnected and lowered downwards through the engine compartment, then withdrawn from the front underside of the car.
1372 cc engine/
transmission - removal
Warning: Refer to the beginning of Section 9 before starting any work.
2 Depressurize the fuel system as described in Section 9 of this Chapter.
3 Disconnect the battery negative lead.
4 Mark the position of the hinges on the underside of the bonnet, then with the aid of an assistant, unscrew the hinge bolts and lift the bonnet clear of the car. Store the bonnet in a safe area.
5 Drain the engine coolant.
6 Drain the engine and transmission oils.
7 Disconnect and remove the air filter.
8 Disconnect the coolant hoses from the engine, including the hose to the inlet manifold.
9 Detach the ignition coil (HT) lead from the distributor.
10 Compress the retaining clip and detach the engine idle speed actuator lead from the SPi unit (photo).
7C.10 Engine idle speed actuator/SPi unit lead connection (arrowed)
11 Disconnect the brake servo vacuum pipe from its connector on the inlet manifold.
12 Disconnect the throttle cable from the SPi unit.
13 Disconnect the engine speed sensor lead.
14 Release and detach the reversing light lead from the switch on the transmission (photo).
7C.14 Reversing light switch and