Cylinder Head Assembly: Service and Repair

1. Remove timing belt cover, timing belt, rocker assembly and camshaft.
2. Remove exhaust manifold, then disconnect wiring harnesses from intake manifold.
3. Remove air suction valve and pipe, if applicable.
4. Remove intake manifold attaching bolts, then the intake manifold together with carburetor.

Fig. 30 Cylinder Head Bolt Tightening Sequence:

5. Remove cylinder head bolts in reverse sequence as that shown in Fig. 30, then remove cylinder head from crankcase.
6. Using suitable valve spring compressor tool, compress valve springs and remove retainer keys.
7. Remove retainers, springs, valves and valve seals.
8. Coat valve seals with engine oil, then install seals using tool 398852100 or equivalent. Intake and exhaust seals are not interchangeable. Intake seals measure .512 inch high, while exhaust seals are .425 inch high. Ensure seals are installed correctly.
9. Coat valve stems with engine oil, then install valves into guides.
10. Install springs, with close-coiled end facing cylinder head, and retainers, then compress spring and install retainer key. Tap retainer lightly with mallet to seat key.
11. Install cylinder head onto crankcase using new gaskets.
12. Apply engine oil to head bolt threads, then install bolts through cylinder head and into crankcase.
13. Torque cylinder head bolts according to sequence shown, in 4 steps as follows:

1. 39 Nm (29 ft.lbs)
2. 73 Nm (54 ft.lbs)
3. Back head bolts off at least 90° in reverse order of tightening sequence.
4. 70 - 77 Nm (51 - 57 ft.lbs)

14. Install intake manifold and carburetor assembly. Tighten bolts to specifications.
15. Install air suction valve and pipe, if applicable, then reconnect wiring harnesses at intake manifold.
16. Install exhaust manifold and tighten bolts to specifications.
17. Install camshaft, rocker assembly, timing belt and timing belt cover.