Elements of the drive of the distribution mechanism of a carburetor engine
1 - bolt, 9-12 Nm; 2 - chain guide; 3 - exhaust camshaft sprocket; 4 - intake camshaft sprocket; 5 - chain tensioner; 6 - bolt, 6-8.5 Nm; 7 - bolt, 6-12 Nm; 8 - chain tensioner; 9 - bolt, 100-130 Nm; 10 - upper chain; 11 - chain guide; 12 - circular section seal; 13 - bolt, 6-8.5 Nm; 14 - intermediate sprocket shaft; 15 - chain tensioner bar; 16 - support pin, 13-19 Nm; 17 - bolt, 45-60 Nm; 18 - intermediate sprocket; 19 - chain guide; 20 - bolt, 13-19 Nm; 21 - lower drive chain; 22 - crankshaft sprocket; 23 - oil pump remote element; 24 - timing gear drive cover; 25 - belt pulley; 26 - bolt, 135-155 Nm
Position of upper and lower chain marks
1 - 16 links between marks (2) and (3); 2 - chain mark (silver color); 3 - chain mark (silver color); 4 - 22 links between marks (3) and (6); 5 - 16 links between marks (2) and (6); 6 - chain mark (silver color); 7 - lower chain mark (silver color); 8 - lower drive chain; 9 - mark on the intermediate shaft sprocket; 10 - upper chain; 11 - lower chain mark (silver color)
1. Unscrew all panels installed under the front of the car.
2. Place the front section on supports, unscrew the right wheel and unscrew the shield in the front right wheel arch.
3. Drain the coolant as described in Chapter Cooling and heating systems.
4. Remove the alternator and power steering pump drive belts. Unscrew the pump and console from the engine. Do not disconnect the hoses.
5. Remove the exhaust pipe completely.
6. Attach the engine to the hoist with cables and remove the front engine mount. This is the bracket shown in illustrations.
7. Remove all spark plugs.
8. Remove the cylinder head cover. To avoid overtightening the cover when loosening, you must follow a certain sequence. It is shown in the illustration below.
Sequence of loosening the cylinder head cover bolts.
9. Turn the crankshaft (by placing a socket head on the crankshaft belt pulley bolt), until the mark on the belt pulley is aligned with the pointer on the timing gear drive cover (see illustration below). In this position of the crankshaft, the piston of the 1st cylinder is in the TDC position of the end of the compression stroke.
When the piston of the 1st cylinder is in the TDC position, the pointer (1) and the "0" mark on the belt pulley (2) must coincide.
10. Remove the distributor cap and inspect the distributor head. The rotor should be in the position shown in illustrations. To remember this installation position, draw a line on the edge of the distributor housing opposite the middle of the runner. Then remove the ignition distributor.
11. Unscrew the camshaft sprocket cover.
12. Remove the water pump belt pulley.
13. Remove the thermostat housing.
14. Remove the chain tensioner. It is secured with two bolts.
15. Referring to the illustration below, check that both timing marks of the camshaft sprockets are aligned with each other. Then remove the inner chain tensioner on the left side and the chain guide on the right side.
View of installed sprockets, tensioner and chain guide. Arrows indicate mounting bolts
1 - camshaft sprocket control marks; 2 - chain guide; 3 - chain tensioner; 4 - intermediate sprocket
16. Loosen and remove the camshaft sprocket bolts. Hold the shafts from turning while doing this. Remove both sprockets, removing the chain at the same time. Do not turn the camshafts any further, as this will cause the valves to hit the pistons. If you only need to remove the cylinder head, tighten the chain and tie it down.
17. Loosen the camshaft bearing cap bolts in several passes in the sequence shown in the illustration. Mark the position of the caps and remove them. Remove both camshafts.
Sequence of loosening camshaft bearing caps.
18. Loosen the cylinder head bolts starting from the edges to the middle in several passes in the sequence shown in the illustration and remove the cylinder head. The intake manifold and exhaust manifold remain on the cylinder head. If the head is stuck to the gasket, you can tap it with a rubber mallet. Never try to remove the head by inserting a screwdriver between the sealing surfaces. Carefully place the cylinder head on a workbench if it is to be disassembled or repaired.
Sequence of loosening cylinder head bolts.
19. Remove the intermediate sprocket shaft from the reverse side.
20. Remove the upper drive chain.
21. Check that the engine is securely suspended on the lift and remove the engine center beam.
22. Remove the oil pan and oil suction screen (Section Removal and installation the oil pan).
23. Holding the crankshaft from turning (put the gear on) loosen the crankshaft belt pulley bolt. Press the pulley with two tire irons.
24. Place a mobile lift under the engine and lift the engine. Place a wooden shim between the lift and the engine. Unscrew the front engine mount from the suspension.
25. Unscrew the timing cover. One bolt is inserted into the water pump.
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26. Remove the parts from the end of the engine shown in the illustration below.
View of the installed lower chain
1 - lower drive chain; 2 - chain guide; 3 - oil pump drive distance ring; 4 - intermediate sprocket; 5 - chain guide; 6 - crankshaft sprocket
27. Installation of the timing gear drive and cylinder head is carried out in the following sequence illustrations the individual elements of the distribution mechanism drive with tightening moments are shown.
28. Check that the piston of the 1st cylinder is in the TDC position. Both keys in the crankshaft should be vertical.
29. Install the chain guide.
30. Hammer in the crankshaft sprocket and apply the lower drive chain. The sprocket has a mark, and the silver link should fit on the tooth with the mark.
31. The sprocket should be installed with the mark facing out. The other silver link is symmetrical, so the chain can be applied in any way. Pull the chain tight and tie it at the top so that it cannot slip off.
32. Install the timing gear drive cover:
- Cover the surface of the lid with sealant.
- Check again that the marks on the chain and sprocket match.
- Align the oil pump drive spacer with the pump.
- Press the chain on one side of the guide so that it cannot touch the cover seal.
- Insert two new O-rings into the cover.
- When installing the cover, be careful not to damage the seal.
33. Install the front engine mount.
34. Install the oil suction screen and oil pan (Section Removal and installation the oil pan).
35. Install the crankshaft belt pulley and tighten the bolt.
36. Install the engine center beam (see illustration).
37. Align the large intermediate shaft sprocket so that the mark on the sprocket aligns with the silver chain link. Then, using the illustration, place the top chain so that the mark on the small star matches the silver link of the top chain.
38. Both marks on the intermediate shaft sprockets should face outward. Insert the intermediate shaft sprockets from the rear.
39. Install the cylinder head with a new gasket. The cylinder head bolts are fitted with washers with the flat side facing the head. Install the head with the intake manifold and exhaust manifold and tap it in place with a rubber mallet. Screw in all the bolts.
40. Tighten the cylinder head bolts in the reverse order to that shown in illustrations. Lubricate the bolt threads, underside of the bolt heads and washers with oil and tighten all bolts by hand.
41. Tightening of bolts is carried out as follows:
42. Tighten all bolts according to the diagram on illustrations with a force of 29 Nm.
43. Tighten all bolts according to the diagram on illustrations with a force of 60 Nm.
44. Loosen all bolts completely.
45. Tighten all bolts according to the diagram in Illustration 4.78 to 30 N·m.
46. Tighten all bolts to a certain angle in the sequence shown in illustrations.
47. All bolts should be tightened to an angle of 50 - 55°. To maintain the angle correctly, you will need a template, which you should make yourself. Cut a circle out of cardboard and divide it into four equal segments of 90°. Divide one of the segments to obtain an angle of 45°. Mark the area 50 - 55° under the 45° line, as shown in the illustration. Exactly in the middle of the template, cut a square hole the size of the socket head and extension you will be using. When tightening, proceed as follows:
- Place the template on the extension and insert the extension into the socket head.
- Place the head on the bolt (15) (see illustration) and align point "0" with any point on the cylinder head.
- Now tighten the bolt until the 50 - 55° mark is reached
- Tighten the remaining bolts in the same manner, maintaining the angle as accurately as possible.
View of a homemade angular template for a carburetor engine.
48. If you do not use a template, you can tighten the bolts to 60 N·m after they have been tightened to 30 N·m. Then tighten the bolts from the outside (bolts 1 to 5 on the illustrations) with a force of 6.5 - 8.5 Nm.
49. Lock the chain drive and tighten the intermediate gear bolt.
50. Install the camshafts, camshaft bearing caps and distributor. Tighten the camshaft bearing cap bolts in the reverse order to that shown in illustrations. Lubricate the camshaft bearing journals well. After replacing valve parts or camshafts, adjust the valve clearance as described below.
51. Insert the camshaft sprockets into the chain and screw them onto the shafts. In doing so, refer to the illustration and count the number of links between the silver links on the upper side. Each sprocket has one tooth with a mark, which must be inserted into the silver link. Also, the mark on the intermediate shaft sprocket must be aligned according to the illustration, i.e. the marks on the camshaft and intermediate shaft sprockets must coincide with the silver links. The guides inside the camshaft sprockets will be in the position shown.
A properly assembled upper drive chain with sprockets installed
1 - 16 links; 2 - left mark; 3 - 22 links; 4 - right mark; 5 - 16 links; 6 - bottom mark; 7 - marks on the stars
52. Carefully turn both camshafts (the crankshaft must also rotate so that the valves cannot hit the pistons), until both guide pins are in the position shown in the illustration. In this position, place the sprockets on the shafts (the pins should fit into the guides in the sprockets) and insert the bolts. Tighten the bolts to the required torque. Check again that the marks in the illustration below match.
Both guide pins must be in the position shown before the sprockets can be placed on them.
53. Install the inner chain tensioner and chain guide as per illustrations. Check that the tensioner locking hook is free.
54. Screw in the chain tensioner from the outside. Slowly turn the crankshaft to check that the crankshaft drive can rotate freely. Set the piston of the 1st cylinder to the TDC position.
55. Lubricate the thermostat housing gasket with sealant and screw it on.
56. Screw on the water pump belt pulley.
57. Install the ignition distributor. The receiving slot on the end of the camshaft should be horizontal.
58. Screw on the camshaft sprocket cover.
59. Apply a 3mm wide bead of sealant to the semi-circular seals and insert them into the cylinder head beds. Align them well so that the top side is flush with the cylinder head surface.
60. Coat the cylinder head cover gasket with sealant and install the cover.
61. Tighten the bolts in the reverse order to that shown in illustrations.
62. All other work should be carried out in the reverse order of removal.