Peugeot 205 Manual
Cylinder head - removal and refittingXV, XW and XY engines in-car repair procedures / Cylinder head - removal and refitting
Note: If the crankshaft is to be rotated after removal of the cylinder head (for cleaning the pistons) it will be necessary to use the Peugeot special tool to hold the camshaft sprocket, or fabricate a suitable alternative. If it will not be necessary to rotate the crankshaft, the home-made tool described in the text will suffice.
1 Disconnect and remove the battery, as described in Chapter 5A.
2 Remove the air cleaner, complete with mounting brackets, hot air hose and inlet hose, with reference to Chapter 4A. Also remove the inlet cowl.
3 Drain the cooling system, as described in Chapter 1.
4 Remove the engine oil filler/crankcase ventilation cap and disconnect the hoses from the inlet cowl and carburettor.
5 Chock the rear wheels then jack up the front of the car and support it on axle stands (see “Jacking and vehicle support”).
6 Disconnect the gearchange selector and engagement rods with reference to Chapter 7A.
Unscrew the engagement rod nut. Make sure that the gears are in neutral.
7 Unscrew the bolt and nuts, and disconnect the exhaust downpipe from the exhaust manifold.
8 Loosen the left-hand engine mounting nuts beneath the battery tray so that the mounting is lowered by approximately 4.0 mm.
9 Disconnect the heater hoses from the bulkhead, water pump and cylinder head outlet.
10 Remove the fuel pump, as described in Chapter 4A.
11 Disconnect the top hose from the thermostat housing.
12 Disconnect the temperature sender wiring.
13 Remove the distributor, as described in Chapter 5B.
14 Disconnect the spark plug HT leads and remove them from the rocker cover.
15 Disconnect the throttle and choke cables, as described in Chapter 4A.
16 Disconnect the brake servo vacuum hose from the inlet manifold (if applicable) and place to one side.
17 Unscrew and remove the two bolts securing the right-hand rear engine mounting to the subframe (see illustration).
7.17 Right-hand rear engine mounting bolts
18 Using a suitable long bar inserted through the right-hand rear engine mounting bracket, lever up the rear of the engine as far as possible, without damaging the radiator, and support with a block of wood (see illustration).
7.18 Lever up the engine and support it on a wooden block
If necessary, loosen the left-hand engine mounting to gain extra height. Make sure that the right-hand front mounting is not damaged by excessive twisting.
19 Unbolt the rocker cover and remove the gasket.
20 Turn the engine on the crankshaft pulley nut until the key slot in the camshaft is facing upwards, then remove the ignition timing aperture cover and turn the engine as necessary until the mark on the flywheel is aligned with the TDC mark on the timing plate (refer to Chapter 5B if necessary).
Pistons No 2 and 3 will be at TDC.
21 Extract the fuel pump plunger from the timing cover (see illustration).
7.21 Removing the fuel pump plunger
22 Unbolt the access plate from the top of the timing cover.
23 Unscrew and remove the camshaft sprocket retaining bolt from the end of the camshaft using an Allen key (retain the sprocket with a suitable bar) (see illustration).
7.23 Unscrew and remove the camshaft sprocket bolt
24 Loosen the four bolts securing the timing cover to the cylinder head (see illustration).
7.24 Loosen the bolts securing the timing cover to the cylinder head
25 Progressively unscrew the cylinder head bolts in the order shown (see illustration), and recover the nuts from their channels in the crankcase.
7.25 Sequence for tightening or loosening the cylinder head bolts
26 Remove the head bolts and lift off the rocker shaft assembly (see illustration). It may be necessary to leave one or two bolts in the assembly if they foul the bulkhead due to insufficient engine height.
7.26 Removing the rocker shaft assembly
27 Loosen the camshaft thrust plate bolt, pull out the plate and temporarily retighten the bolt (see illustration).
7.27 Loosening the camshaft thrust plate bolt
28 The camshaft sprocket must now be supported in its normal position while the cylinder head is removed. If it is allowed to drop it will not be possible to lift it again without releasing the timing chain tensioner which will necessitate removal of the timing cover. Peugeot dealers use a special mandrel, tool number 70132, but as this is unlikely to be available to the home mechanic it is suggested that a plate and bolt are used, together with the access plate (see Tool Tip).
29 Slide the camshaft from the fuel pump eccentric and camshaft sprocket and let it rest in the cylinder head (see illustration).
7.29 Slide the camshaft from the fuel pump eccentric (arrowed)
30 Before removing the cylinder head the following must be noted. The cylinder head is positioned during assembly by means of two dowels. When removing the cylinder head it is most important not to lift it directly from the cylinder block; it must be twisted slightly. This action prevents the cylinder liners from sticking to the cylinder head face and being lifted with it, thus breaking their bottom seals.
Before the cylinder head can be twisted, the dowel at the flywheel end must be tapped down flush with the top of the cylinder block, using a drift (see illustration).
7.30 Driving the cylinder head dowel down flush with the block face
31 Remove the four timing cover-to-cylinder head bolts then move the flywheel end of the cylinder head sideways slightly to release the gasket.
32 Lift the cylinder head from the block and remove the gasket without disturbing the liners. Do not turn the engine over as this also will break the liner bottom seals. If further work is to be carried out on the engine, such as cleaning the tops of the cylinder liners, they should be clamped in position using two cylinder head bolts, metal tubing, and large washers (see illustration).
7.32 Using washers, tubing and the cylinder head bolts to clamp the liners in position
Preparation for refitting Note: As mentioned at the beginning of this Section, the camshaft sprocket must be supported in such a way that it will be allowed to rotate as the crankshaft is turned to clean the pistons. The Peugeot special tool locates through the sprocket retaining bolt hole and is bolted to the front of the timing cover. If this tool cannot be obtained, a suitable alternative can be easily fabricated.
33 With the camshaft sprocket supported so as to allow rotation, commence the cleaning operation as follows.
34 The mating faces of the cylinder head and cylinder block/crankcase must be perfectly clean before refitting the head. Use a hard plastic or wood scraper to remove all traces of gasket and carbon; also clean the piston crowns. Refer to paragraph 32 before turning the crankshaft. Take particular care during the cleaning operations, as aluminium alloy is easily damaged. Also, make sure that the carbon is not allowed to enter the oil and water passages - this is particularly important for the lubrication system, as carbon could block the oil supply to the engine’s components. Using adhesive tape and paper, seal the water, oil and bolt holes in the cylinder block/crankcase.
To prevent carbon entering the gap between the pistons and bores, smear a little grease in the gap. After cleaning each piston, use a small brush to remove all traces of grease and carbon from the gap, then wipe away the remainder with a clean rag. Clean all the pistons in the same way.
35 Check the mating surfaces of the cylinder block/crankcase and the cylinder head for nicks, deep scratches and other damage. If slight, they may be removed carefully with a file, but if excessive, machining may be the only alternative to renewal.
36 If warpage of the cylinder head gasket surface is suspected, use a straight-edge to check it for distortion. Refer to Part D of this Chapter if necessary.
37 Check the condition of the cylinder head bolts, and particularly their threads, whenever they are removed. Wash the bolts in suitable solvent, and wipe them dry. Check each for any sign of visible wear or damage, renewing any bolt if necessary. Measure the length of each bolt, to check for stretching (although this is not a conclusive test, in the event that all ten bolts have stretched by the same amount). Although Peugeot do not actually specify that the bolts must be renewed, it is strongly recommended that the bolts should be renewed as a complete set whenever they are disturbed.
38 Before refitting the head, the nuts must be retained in their channels. The use of rubber or plastic tubing is very effective, or wooden wedges may be used (see illustration).
7.38 Using rubber tubing to hold the cylinder head nuts in position
39 Commence refitting by lifting the location dowel (paragraph 30) and retaining it by inserting a short pin in the hole provided - leaving room for the bolt to pass through (see illustration).
7.39 Using a pop rivet to retain the cylinder head location dowel
40 Locate a new cylinder head gasket on the cylinder block, making sure that all the holes are aligned.
41 Apply a silicone sealing compound to the timing cover mating surface (see illustration).
7.41 Applying sealing compound to the timing cover
42 Lower the cylinder head into position over the dowels.
43 Fit the four timing cover-to-cylinder head bolts finger tight.
44 Slide the camshaft into the sprocket and fuel pump eccentric. Slight rotation of the eccentric may be necessary in order to align its key with the camshaft slot.
45 Push the thrust plate fully into the camshaft groove then tighten the bolt.
46 Unbolt and remove the sprocket retaining tool.
47 Insert the sprocket retaining bolt and tighten it with an Allen key while holding the sprocket with a bar through one of the holes resting on packing pieces.
48 Apply a silicone sealing compound to the access plate then refit it and tighten the bolts.
49 Refit the rocker shaft assembly with the two location pegs towards the front.
50 Insert the head bolts (threads and heads oiled) and tighten them in two stages to the specified torques and in the sequence shown (see illustration 7.25). Note that washers must be fitted beneath the bolt heads on XY7 and XY8 engines.
51 Remove the nut retainers from the cylinder block.
52 Tighten the four timing cover-to-cylinder head bolts.
53 Insert the fuel pump plunger in the timing cover.
54 Adjust the valve clearances (Section 2).
55 Refit the rocker cover with a new gasket.
56 Remove the block of wood and lower the engine to its normal position.
57 Insert and tighten the right-hand rear engine mounting bolts, also tighten the left-hand mounting bolts.
58 Reconnect the brake servo vacuum hose to the inlet manifold (if applicable).
59 Reconnect the throttle and choke cables (Chapter 4A).
60 Refit the distributor and spark plug HT leads (Chapter 5B).
61 Reconnect the temperature sender wiring.
62 Refit the top hose to the thermostat housing.
63 Refit the fuel pump (Chapter 4A).
64 Reconnect the heater hoses.
65 Refit the exhaust downpipe to the exhaust manifold.
66 Reconnect the gearchange rods (Chapter 7A).
67 Lower the car to the ground.
68 Refit the oil filler/crankcase ventilation cap and hoses.
69 Refill the cooling system (Chapter 1).
70 Refit the air cleaner, inlet cowl and inlet hoses.
71 Refit the battery.
72 After the engine has been started and run to full operating temperature, it should be switched off and allowed to cool for at least two hours. Remove the rocker cover.
73 Unscrew the first cylinder head bolt one half a turn and then retighten it to the Stage 2 torque. Repeat the operation on the remaining bolts, one at a time in the sequence specified (see illustration 7.25).
74 Check the valve clearances again and readjust if necessary.