Cylinder Head Replacement - Left

Cylinder Head Replacement - Left

Tools Required
- J36660-A Torque Angle Meter
- J42385-100 Thread Repair Kit (Cylinder Head/Main Bearing Bolt)

Removal Procedure
1. Remove the valve rocker arms and pushrods.
2. Remove the engine coolant air bleed pipe and covers.
3. Remove the generator bracket.
4. Remove the exhaust manifold.





5. Remove the engine wiring harness ground bolt (5) from the rear of the left cylinder head.
6. Reposition the engine wire harness ground strap (6) away from the cylinder head.

Important: The cylinder head bolts are NOT reusable.





7. Remove the cylinder head bolts. Notice: After removal, place the cylinder head on two wood blocks to prevent damage.
8. Remove the cylinder head.





9. Remove the cylinder head gasket.
10. Discard the gasket.
11. Discard the M11 cylinder head bolts.
12. Clean and inspect the cylinder head.

Installation Procedure

Important:
- Do not reuse the cylinder head bolts. Install NEW cylinder head bolts during assembly.
- Do not use any type of sealant on the cylinder head gasket (unless specified).
- The cylinder head gasket must be installed in the proper direction and position.

Caution: Wear safety glasses in order to avoid eye damage.

Notice: Clean all dirt, debris, and coolant from the engine block cylinder head bolt holes. Failure to remove all foreign material may result in damaged threads, improperly lightened fasteners or damage to components.





1. Clean the engine block cylinder head bolt holes (if required).
Thread repair tool J42385-107 may be used to clean the threads of old threadlocking material.
2. Spray cleaner GM U.S. P/N 12346139, P/N 12377981, Canada P/N 10953463, or equivalent into the hole.
3. Clean the cylinder head locating holes with compressed air.
4. Check the cylinder head locating pins for proper installation.





5. Install the NEW cylinder head gasket onto the locating pins.

Important: When properly installed, the tab on the left cylinder head gasket will be located left of center, or closer to the front of the engine, and the words "This Side Up", and the engine displacement, will be visible.





6. Inspect the gasket for proper installation.





7. Install the cylinder head onto the locating pins and the gasket.
8. Install NEW cylinder head bolts.

Notice: Refer to Fastener Notice in Service Precautions.

Cylinder Head Bolt Tightening Sequence:

9. Tighten the cylinder head bolts.
9.1. Tighten the M11 cylinder head bolts (1-10) a first pass in sequence to 30 Nm (22 ft. lbs.).
9.2. Tighten the M11 cylinder head bolts a second pass in sequence to 90 degrees using the J36660-A.
9.3. Tighten the M11 cylinder head bolts (1,2,3,4,5,6,7,8) to 90 degrees and the M11 cylinder head bolts (9 and 10) to 50 degrees a final pass in sequence using J36660-A.
9.4. Tighten the M8 (11-15) to 30 Nm (22 ft. lbs.). Begin with the center bolt (11) and alternating side-to-side, work outward tightening all of the bolts.





10. Position the engine wire harness ground strap (6) against the cylinder head.
11. Install the engine wiring harness ground bolt (5) to the rear of the left cylinder head.
Tighten the engine wire harness ground bolt to 32 Nm (24 ft. lbs.).
12. Install the exhaust manifold.
13. Install the generator bracket.
14. Install the engine coolant air bleed pipe.
15. Install the valve rocker arms and pushrods.