Cylinder Head Gasket: Service and Repair
Cylinder Head Gasket, Renew
Drain the cooling system, and depressurize the fuel system. Disconnect the exhaust system with the vehicle supported on axle stands. Remove components as required for access to the cylinder head and proceed as follows.
- Rotate the engine to TDC No.1 cylinder.
- Remove the camshaft cover.
- Push back the lock tabs and remove the camshaft sprocket securing bolts (2 Fig. 1). Remove the tab washers (1 Fig. 1).
- Remove the upper chain tensioner valve clamp bolt (1 Fig. 2), remove the clamp (2 Fig. 2) and remove the valve (3 Fig. 2).
- Using a 3 mm Allen key, wind back the tensioner (turn clockwise) until the snail engages in the park position.
- Remove the tensioner housing securing bolt (4 Fig. 2) and withdraw the tensioner assembly.
- Reposition the timing chain between the upper dampers.
- Fit an elastic band to retain the dampers and chain.
- Remove the cylinder head front securing bolts.
- Remove the remaining cylinder head securing bolts/nuts. Remove the upper static damper pedestal assembly and remove the cylinder head.
- Remove and discard the head gasket.
- Remove and discard the exhaust manifold sealing rings.
- Place the cylinder head on suitable blocks on a bench.
- Clean the cylinder heed thoroughly and check the cylinder head and cylinder block for warping, bowing or cracks. Renew if defective.
- Fit a new cylinder head gasket.
- Fit the cylinder head assembly to the engine, ensure no hoses or cables are trapped.
- Refit the upper static damper assembly.
- Tighten the cylinder head bolts with reference to the sequence shown in Fig. 1.
CAUTION: The cylinder head bolts MUST be renewed during assembly and torque tightened as described under Engine, Service and Repair, Service Procedures, SPS Joint Control System.
Note: Ensure that the camshaft is still on TDC using Service Tool 18G 1433A (1 Fig. 2).
- Fit the harness clip and hose bracket to the cylinder head front securing bolts.
- Fit and tighten the front securing bolts.
- Check the camshafts are set at TDC using Service Tool 1 8G 1433A (1 Fig. 2).
- Raise the timing chain from between the upper dampers.
- Remove the elastic band.
- Re-position the chain over the camshafts.
- Fit and engage the sprockets to the chain and camshafts.
- Move all the chain free play to the tensioner side.
- Fit upper chain tensioner tool 18G 1436/A (2 Fig. 3).
- Fit and tighten the tool securing bolts (1 Fig. 3).
- Tension the timing chain.
- Remove the camshaft coupling (12 Fig. 4) from the sprocket (11 Fig. 4) and align the securing bolt holes.
- Fit the tab washers (1 Fig. 4), Fit and tighten the securing bolts (2 Fig. 4). Lock over the tabs.
- Release the tension on the timing chain.
- Slacken off the upper chain tensioner tool securing bolts.
- Remove the upper chain tensioner tool 18G 1436/A (2 Fig. 3).
- Clean the tensioner assembly and gasket faces.
- Fit a new housing gasket (10 Fig. 4). Lubricate and fit a new `O' ring (9 Fig. 4).
- Fit the tensioner to the cylinder head.
- Fit and tighten the tensioner assembly securing bolt (4 Fig. 3).
- Clean the valve assembly and fit new `O' rings.
- Lubricate the tensioner valve.
- Using an Allen key, release the tensioner, ie turn the Allen key anti-clockwise.
- Fit the tensioner valve (3 Fig. 1). Position the clamp (2 Fig. 1) over the valve.
- Tighten the clamp bolt (1 Fig. 1).
- Fit the camshaft cover.
Replace the components removed for access and connect the exhaust system with the vehicle supported on axle stands. Fill the system with coolant.