Cylinder head parts for 2.4 and 2.7 L engines
1. Crankcase ventilation valve; 2. Lid; 3, 15, 18. Gasket; 4. Sealing ring; 5. Adjusting washer; 6. Pusher; 7. Rusks; 8. Plate; 9. Spring; 10. Oil seal; 11. Thrust washer; 12. Guide sleeve 13. Spark plug; 14. Valve; 16. Plug; 17. Tensioner; 19. Camshaft drive gear; 20. Retaining ring; 21. Spring washer; 22. Auxiliary gear; 23. Spring; 24. Exhaust camshaft; 25. Bearing journal cover; 26. Intake camshaft
Sequence of removing camshaft covers
1. Intake camshaft
2. Exhaust camshaft
Tightening order of the intake camshaft journal cover bolts
Tightening order of the exhaust camshaft journal cover bolts
Attention! Before performing the work, prepare two bolts with a thread of 6x1 mm and a length of 16–20 mm, which will be used as auxiliary ones during disassembly (see below).
Removal
1. Remove the cylinder head cover (see subsection 3.1.4).
2. Set the piston of the 1st cylinder to TDC of the compression stroke. Make sure that the dot marks on the driving and driven gears of the camshafts are aligned and located in line with the split plane of the cylinder head and cover.
3. Otherwise, check that the TDC mark of the crankshaft is aligned with the zero division of the scale and turn the crankshaft by 1 revolution.
4. Measure the axial play of each camshaft. To check the axial play, move the camshaft back, set the indicator to zero, and then move the camshaft forward. If the play exceeds the maximum permissible value, the camshaft and/or cylinder head must be replaced.
5. Remove the ignition distributor, if equipped (see subsection 11.5).
6. Loosen the chain tensioner bolts (arrows).
7. Remove the chain tensioner.
8. Mark the chain link opposite the dot mark.
9. Loosen the sprocket bolt while holding the camshaft with a wrench. Remove the distributor drive gear.
10. Carefully remove the sprocket and chain from the camshaft and leave them on the chain guides.
Exhaust camshaft
11. First remove the exhaust camshaft, after securing the auxiliary gear spring.
Attention! Remove the camshafts one by one, keeping them parallel to the cylinder head plane. Otherwise, the cylinder head may break.
12. To secure the spring, turn the camshaft so that the technological hole for the auxiliary bolt is facing vertically upward.
13. Attach the auxiliary gear to the main gear using a pre-prepared bolt with M6 thread and 15–20 mm length.
14. On engines before 1998, remove the bolt and distributor gear.
15. Move the camshaft back, gradually and evenly unscrew the bolts of the camshaft journal cover N1 (see Fig. Sequence of removing camshaft covers).
16. Carefully unscrew the bolts of the remaining camshaft journals, making sure that the camshaft is lifted evenly. If the camshaft is released at an angle, tighten the bolts of cover N3 and, supporting the camshaft by the gear, gradually loosen the bolts.
Intake camshaft
17. Move the camshaft forward, gradually and evenly unscrew the bolts of the camshaft journal cover N1 (see Fig. Sequence of removing camshaft covers).
18. Carefully unscrew the bolts of the remaining camshaft journals, making sure that the camshaft is lifted evenly. If the camshaft is released at an angle, tighten the bolts of the middle cover (N3) and, supporting the camshaft by the gear, gradually loosen the bolts.
19. Remove the intake camshaft.
20. Wipe the oil off the tappet adjusting washers, mark them with a marker and remove the tappets and adjusting washers.
21. Store the bearing journal caps, tappets and washers in the order in which they were installed.
Examination
1. Clamp the intake camshaft in a soft jaw vice by the hexagonal journal.
2. Using a double-pin wrench, turn the auxiliary gear clockwise, then loosen the auxiliary bolt securing the main and auxiliary gears and gently release the force, allowing the auxiliary gear to turn counterclockwise until the spring is completely released.
3. Remove the auxiliary gear retaining ring.
4. Remove the spring washer (1), auxiliary gear (2) and auxiliary gear spring (3).
5. Measure the distance between the ends of the auxiliary gear spring in a free state and compare with the standard. If the distance differs from the standard, replace the spring.
6. Check the condition of the tappets. Chips and deep wear are not allowed.
7. Check the bearing journals and camshaft cams for signs of wear - grooves, pits, metal drag and signs of overheating (bluish areas, or painted areas). Check each cam for any peeling of the hardened layer.
8. Measure the size of each camshaft lobe and compare with the standard. If the size of at least one lobe is smaller than the standard, replace the camshaft.
9. Measure the diameter of the camshaft bearing journals and compare with the standard. If the diameter of at least one bearing journal is less than the standard, replace the camshaft.
10. Check the bearing journal clearances for each camshaft as follows.
11. Clean the camshaft journals and journal caps in solvent.
12. Carefully place the camshaft in the cylinder head without the tappets, adjusting washers and auxiliary gear. No oil is allowed on the journals.
13. Place pieces of plastic calibration wire across each camshaft journal.
14. Install the camshaft journal covers so that the arrows point towards the timing belt.
15. Tighten the bolts to the specified torque by turning each bolt 1/4 turn at a time.
Caution! Turning the camshaft with the plastic gauge inserted is not permitted.
16. Loosen the bolts and remove the covers.
17. Compare the width of the crushed wire (at the widest point) with a scale on the packaging.
18. If the clearance in at least one journal exceeds the norm, the camshaft and/or cylinder head must be replaced.
19. Use your fingernail or a credit card to scrape off any remaining plastic, being careful not to scratch the bearing collar or the inside of the lid.
20. With the bearing journal covers temporarily installed, check the clearance in the engagement of the camshaft gears. Holding one of the camshafts by the hexagonal journal with a wrench, check the amount of movement of the gear of the other camshaft. Compare the result with the standard. If the clearance is higher than the standard, replace both camshafts.
Installation
Intake camshaft
1. Lubricate and install the tappets and adjusting washers in their original places, having previously lubricated them with molybdenum grease.
2. Upper bolts securing the clutch housing to the cylinder block.
3. Lubricate the bearing journals and camshaft lobes with molybdenum grease. Lubricate the thrust portion of the intake camshaft.
4. Install the intake camshaft into the cylinder head with the locating pin (1) facing upward.
5. Move the camshaft forward and install the bearing journal covers in their original places, observing the numbering and orientation of the arrows, which should be directed towards the toothed belt.
6. Tighten in the correct sequence (see Fig. Tightening order of the intake camshaft journal cover bolts), cover bolts until they touch the cylinder head. Do not tighten the bolts completely.
7. Tighten all bolts to the specified torque.
Exhaust camshaft
8. Assemble the exhaust camshaft with springs and auxiliary gear, secure all parts with a retaining ring.
9. Lubricate and install the tappets and adjusting washers in their original places, having previously lubricated them with molybdenum grease.
10. Lubricate the camshaft journals and cams with molybdenum grease.
11. Align the marks (2) on the camshaft gears. The exhaust camshaft alignment pin (1) must face upwards.
12. It should be taken into account that the design of the valve timing of the engine in question does not allow for traction connections. The cap bolts should be tightened in this position, after which the camshaft should be turned back to set it to the position corresponding to TDC, in which the contact surfaces touch evenly, without obstacles from the forces of the springs acting on the cams.
13. Rotate the exhaust camshaft over the intake camshaft and install it in place. Rotate the camshaft in both directions to ensure proper seating in the bearings.
14. Move the camshaft forward and install the bearing journal covers in their original places, observing the numbering and orientation of the arrows, which should be directed towards the toothed belt.
15. Tighten the cover bolts in sequence until they touch the cylinder head (see Fig. Tightening order of the exhaust camshaft journal cover bolts). Do not tighten the bolts completely.
16. Tighten all bolts to the specified torque in several stages.
17. Turn the camshafts so that the auxiliary bolt is at the top and unscrew the bolt. Make sure that the camshafts rotate smoothly.
18. Align the marks on the gears. Make sure that the TDC mark on the crankshaft pulley is aligned with the TDC mark.
19. Install the chain with the sprocket, checking that the marks match.
20. Install the distributor gear and tighten the bolt.
21. Release the tensioner lock and push in the plunger.
22. Secure the plunger by placing the hook on it.
23. Turn the crankshaft until the hook comes off the plunger pin.
24. If the plunger does not come out, press on the tensioner shoe and release the plunger hook.
25. Install the tensioner, replacing the gasket.
26. Then the installation is carried out in the reverse order. If necessary, adjust the valves and ignition timing (see subsection 11.6).