Cylinder Head Gasket: Service and Repair
CYLINDER HEAD GASKETREMOVAL AND INSTALLATION
CAUTION: If the vehicle is equipped with the Brembo(TM) disc brake, during maintenance, take care not to contact the parts or tools to the caliper because the paint of caliper will be scratched.
Pre-removal & Post-installation Operation:
Removal Steps 1-8:
Removal Steps 9-30:
Removal Steps 31-32 & Required Special Tool:
REMOVAL SERVICE POINT
[[A]] CYLINDER HEAD BOLTS REMOVAL
Using special tool MB991654, loosen the cylinder head bolts in two or three steps in the order shown in the illustration.
NOTE: If the cylinder head bolts cannot be pulled out due to the washer being trapped in the valve spring, raise the bolt slightly, then remove it while holding it by using a magnet.
INSTALLATION SERVICE POINTS
]]A[[ CYLINDER HEAD GASKET INSTALLATION
CAUTION: Do not allow any foreign materials to get into the coolant passages, oil passages and cylinder.
1. Remove the gasket from the cylinder head and cylinder block.
2. Assemble to the cylinder block so the cylinder head gasket identification mark "63" is at the top surface and on the exhaust side.
]]B[[ CYLINDER HEAD BOLTS INSTALLATION
1. Check that the nominal length of each cylinder head bolt meets the limit. If it exceeds the limit, replace the bolt with a new one.
Limit (A): 99.4 mm (3.91 inches)
2. Apply a small amount of engine oil to the thread of the bolts and to the washers.
3. Use special tool MB991654 to tighten the cylinder head bolts as follows:
1. Tighten the cylinder head bolts to 78 ± 2 Nm (58 ± 1 ft. lbs.) in the order shown.
2. Loosen the bolts fully in the reverse order of that shown.
3. Tighten the cylinder head bolts to 20 ± 2 Nm (15 ± 1 ft. lbs.) in the order shown.
4. Apply a paint mark to the heads of the cylinder head bolts and cylinder head, then tighten 90 degree angle as shown.
CAUTION: The bolt is not tightened sufficiently if the bolt is tightened less than 90 degree angle.
5. Tighten the bolt an additional 90 degree angle as shown. Then check to see that the paint mark on the head of the cylinder head bolts and the paint mark on the cylinder head are aligned.
6. If tightening the bolt 90 degree angle results in moving the paint mark on the bolt past the paint mark on the cylinder head, remove the bolt and start over from step 1.
]]C[[ O-RING/FUEL HIGH-PRESSURE HOSE INSTALLATION
CAUTION: Do not let any engine oil get into the fuel rail.
1. Apply a small amount of new engine oil to the O-ring.
2. Turning the fuel high-pressure hose to the right and left, install it onto the fuel rail, while being careful not to damage the O-ring. After installing, check that the hose turns smoothly.
3. If the hose does not turn smoothly, the O-ring is probably being clamped. Disconnect the fuel high-pressure hose and check the O-ring for damage. After this, re-insert it to the fuel rail and check that the hose turns smoothly.
4. Tighten the fuel high-pressure hose mounting bolts to the specified torque.
Tightening torque: 5.0 ± 1.0 Nm (44 ± 9 inch lbs.)
]]D[[ OIL RETURN TUBE GASKET INSTALLATION
The oil return tube gasket should be replaced with a new one. Set the convex part to the position shown in the illustration.
NOTE: There is no specific direction indicated for installing the turbocharger side of the oil return tube gasket.
]]E[[ EYE BOLT INSTALLATION
CAUTION: When tightening the eye bolt, hold the oil pipe joint with a spanner so that it does not rotate with the eye bolt.