Note. When installing the cylinder head, replace the gasket and bolts.
Withdrawal
1. Drain the coolant (see chapter 1).
2. Remove the intake and exhaust manifolds.
3. Remove the camshafts and tappets as indicated in paragraph 10.
4. Trace the wiring from the camshaft position sensors and disconnect their electrical connectors. Turn out bolts of fastening of gauges and remove them from a head of cylinders.
5. Remove the two slotted screws and remove the secondary chain damper from the cylinder head (pic. 11.5).
6. Turn out bolts of fastening of a cover of a chain to a head of cylinders.
7. Remove the thermostat as directed in chapter 3.
8. Turn out two bolts and disconnect a tube of a cooling liquid from a head of cylinders from an inlet. For easier access, disconnect the oil supply pipe to the VANOS camshaft adjuster from the rear side of the oil filter housing (pic. 11.8). When installing, replace the sealing washers of the fitting.
9. On the left side of the cylinder head, disconnect the electrical connectors from the temperature sensor.
10. Gradually loosen the cylinder head bolts in the reverse order to that shown in fig. 11.27.
11. Turn out bolts and pull out washers. Please note. that some washers could get stuck in the holes and it is not so easy to remove them from there.
12. Separate the head from the block by swinging it across the block. Do not press the head from the block with any tool, as this can damage the mating surfaces.
13. To remove the head, ideally, two assistants are required. Ask one of them to keep the camshaft drive chain in tension. With a second assistant, lift the cylinder head and remove it from the block. As the head rises, have your assistant pull the chain through the hole in the head. After removing the head, tie the chain to the block with a piece of wire.
14. Remove the cylinder head gasket.
Inspection
15. Disassembly and assembly of the cylinder head is described in chapter 2B.
16. Clean the mating surfaces of the head and block. Use a scraper to scrape off the remnants of the gasket and soot. Also clean the piston bottoms. Be careful, especially with the surfaces of the head and block - aluminum parts are easily damaged. Do not allow scraped particles to enter the channels of the lubrication and cooling systems. Seal all channels and bolt holes in the cylinder block with tape. To prevent carbon deposits from getting into the gaps between the pistons and cylinder bores, coat the gaps with grease. After cleaning each piston, turn the crankshaft so that the piston goes down and wipe off the grease and soot from the cylinder surface with a clean rag.
17. Inspect the block and cylinder head for nicks, deep scratches, and other damage. Minor damage can be repaired with a fine file, but more serious damage requires machining. but this is a job for professionals.
18. If warping of the head is suspected, check this assumption by placing the edge of a steel ruler on the surface and measuring the gap between the ruler and the surface with flat feeler gauges.
19. Clean the bolt holes in the cylinder block with a clean cloth wrapped around a screwdriver. Remove all fluids from holes. including oil, otherwise high pressure may be created in the closed hole when the bolts are tightened, which will burst the block.
20. Check the threads of the bolts and holes in the block for damage. Drive the thread with a die and tap of the appropriate size.
Installation
Attention! If the camshafts have been removed, heed the warning in paragraph 10 about extending the tappets.
21. To prevent the valves from sticking into the pistons after installing the camshafts, before returning the crankshaft to the TDC position, take a break of at least the following:
22. Before installing the head on the block, their mating surfaces must be sterile clean. The bolts and bolt holes in the block must be absolutely intact: the bolts must be screwed in and out by hand without excessive friction and jamming. Make sure the head dowel pins are in place in the cylinder block.
Attention! To eliminate the possibility of pistons sticking into open valves when installing the cylinder head, all pistons must be removed from TDC. Turn the crankshaft to TDC before proceeding with assembly. And check if the latch is inserted into the flywheel), then turn the crankshaft counterclockwise 30°.
23. Apply a thin bead of Drei Bond 1209 sealant to the mating surfaces of the chain cover to the cylinder block.
24. Place a new cylinder head gasket on the block so that the dowel pins fit into the gasket holes (pic. 11.24). Usually the gasket is marked. defining its top and bottom. Please note that a thicker gasket is available for a ground head (by 0.3 mm).
25. Lay the cylinder head on the block, making sure that the dowel pins are in the holes.
26. Prepare a set of new bolts. Lubricate the threads of the bolts, the undersides of their heads, and the washers with engine oil. Screw the bolts into the holes and tighten them hand-tight as far as possible. Make sure that the washers do not warp.
Note. Do not put a washer on the bolt if there is already an old washer in the hole that could not be removed from there.
27. Tighten the bolts in the sequence shown in fig. 11.27. in several steps as indicated in the Technical data.
28. Screw and tighten bolts of fastening of a cover of a chain to a head of cylinders.
29. Install the secondary circuit damper and securely attach it to the cylinder head with screws.
30. Install the camshafts and tappets as indicated in paragraph 10.
31. Rotate the crankshaft 30°clockwise to return it to TDC. Secure the shaft in this position by inserting a retainer into the flywheel.
32. The rest of the installation is carried out in the reverse order of removal. Finally, fill the cooling system.