Cylinder Head Gasket Replacement

GENERAL INFORMATION

Cylinder head

1. Cylinder head cover gasket (always replace)

2. Bearing bushing

3. Rubber bushing

4. Main bearing cap

5. Rear camshaft oil seal (always replace)

6. Rear camshaft gear

7. Rear cover

8. Hydraulic valve lifter

9. Valve rotator

10. Upper valve spring retainer

11. Valve stem oil seals

12. Valve spring

13. Valve spring seat

14. Valve

15. Swirl chamber

16. Valve seat

17. Cylinder head gasket (always replace; gaskets of different thicknesses are available depending on piston size)

18. Sealant application points (apply sealant to these points before installing the cylinder head cover gasket)

19. Camshaft

20. Front camshaft oil seal (always replace)

21. Bearing bushing

22. Front cover

23. Rubber bushing

24. Spring

25. Front camshaft gear

26. Side plate (for camshaft gear)

Cylinder head bolt numbering

Cylinder head bolt tightening sequence

Removal

PROCEDURE

1. Disconnect the battery ground cable.

WARNING: This will erase electronic memory, such as the radio code. Read the instructions in subsection 7 before disconnecting the battery.

2.

2. Completely drain the coolant and collect it in a container.

3. Remove the exhaust muffler inlet pipe.

4. Disconnect all coolant hoses from the cylinder head.

5. Remove the air duct.

6. Remove the exhaust manifold heat shield.

7. Remove the exhaust manifold.

8. Remove the cylinder head cover with gasket.

9. Set No. 1 piston to TDC.

Caution: After this, the positions of the crankshaft and camshaft must not change.

10. Remove the timing belt.

11. Loosen the cylinder head bolts in the specified sequence in 3 passes (see illustration Cylinder Head Bolt Numbering).

12. Loosen all bolts by 1/2 turn in the specified sequence.

13. Loosen all bolts by another 1 turn.

14. Remove all bolts.

Caution: The cylinder head may warp or crack if the bolt loosening sequence is not followed.

15. Make sure all hoses and wires running from the cylinder head to the engine and body are disconnected.

16. With an assistant, remove the cylinder head.

Caution: After removal, do not place the cylinder head on its mating surface, as fully open valves may be damaged. Place the cylinder head on two wooden blocks. Installation

PROCEDURE

1. Clean the cylinder head and check for distortion.

2. Check the coolant, oil and fuel hoses for damage and cracks. Replace if necessary.

3. Check the valves and valve seats for wear and damage.

4. Install the cylinder head gasket so that the holes in the cylinder block and in the gasket align.

Caution: Cylinder head gaskets of different thicknesses are available, marked with 1, 2 or 3 notches on the edge. If only the gasket is being replaced, be sure to install a new gasket with the same marking. If the cylinder block, pistons, connecting rods or crankshaft were replaced or repaired, select the gasket thickness according to the piston protrusion (performed in a workshop).

5. Install the cylinder head.

6. Coat the cylinder head bolts and washers with a thin layer of clean engine oil and install them in accordance with the markings (see illustration Bolt Tightening Sequence). Make sure the chamfered side of the washers faces the bolt heads. The flat side of the washer faces the cylinder head.

7. Hand-tighten the cylinder head bolts until they contact the seat with the collar.

8. Then tighten bolts 1 through 10 in 5 passes.

9. On each pass, tighten the bolts in the specified sequence.

10. Tighten bolts 1 through 10 to 40 N·m.

11. Tighten bolts 1 through 10 to 90 N·m.

12. Fully loosen bolts 10 through 1.

13. Tighten bolts 1 through 10 to 40 N·m.

14. Using a torque wrench, turn bolts 1 through 10 an additional 75° in one pass.

15. This requires an angle gauge. If one is not available, tighten bolts 1 through 10 to 90 N·m.

Caution: Tighten the bolts with particular care. The bolts must be tightened in 5 passes. Before tightening, check the accuracy of the torque wrench. Also strictly follow the tightening sequence.

16. Install the timing belt.

17. Install the cylinder head with a new gasket. Apply sealant to the bearing caps 1 and

5.

18. Apply sealant to the opposite mating surfaces of the cylinder head cover.

19. Lightly tighten all bolts to a maximum of 4 N·m.

Caution: If the bolts are overtightened, leaks may occur.

20. Tighten the exhaust manifold to 20 N·m.

21. Install the exhaust manifold heat shield.

22. Install the air duct.

23. Connect all coolant hoses to the cylinder head and secure with clamps.

24. Install the muffler inlet pipe.

25. Connect the battery ground cable.

26. Fill with coolant.