Cylinder Head Installation

CYLINDER HEAD INSTALLATION






1. Remove gasket material:
a. Using a gasket scraper, remove all the gasket material from the cylinder block surface.
b. Clean the cylinder block bolt holes of any residual sealer, oil, or foreign material. Remove any oil with solvent.
c. Clean the cylinder head bolt threads with a wire brush.
d. Coat the bolt threads with engine oil.






2. Inspect top of cylinder block for flatness. Using a precision straight edge and feeler gage, measure the surfaces contacting the cylinder head gasket for warpage.

Maximum Transverse Warpage:
Standard: 0.024 mm (0.0009 in.)
Service Limit: 0.05 mm (0.002 in.) max.

Maximum Longitudinal Warpage:
Standard: 0.08 mm (0.0031 in.)
Service Limit: 0.10 mm (0.004 in.) max.






3. Inspect liner height at four locations around the cylinder bore.

Maximum Installed Liner Height/Depth:
Standard: Flush
Service Limit: +/- 0.013 mm (0.0005 in.) max.






4. Inspect cylinder bore and tops of pistons for debris, deep scratches, excessive carbon built up, etc.
5. Viewing from accessory drive belt and position number one cylinder at 90 degree past TDC (top dead center) clockwise. The crankshaft is correctly positioned when the crankshaft key way and sprocket timing mark are aligned with the cylinder block main bearing cap split line.

NOTICE: The camshaft must be correctly positioned to prevent valve and piston damage.

6. Install a new cylinder head gasket.

NOTICE: Whenever a cylinder block or the head bolts are replaced, install the cylinder head and torque the bolts to 65 Nm (48 ft. lbs.). Next, remove the bolts, coat the threads with engine oil and follow the torque angle procedure steps. Torquing the bolts one time prior to following the torque angle steps will make sure proper clamp load is achieved.





7. Install the cylinder head, aligning it on the dowels:
a. Carefully guide the head into place.
b. Thread the bolts (threads coated with engine oil) in by hand until finger tight.

NOTICE: The following steps must be completed in sequence. This will make sure of uniform bolt tension.

NOTICE: The torque specifications in this article have been updated from the GM service information website.

8. Cylinder head bolt tightening procedure:

Cylinder Head Bolt Tightening Sequence:

a. In sequence, torque the cylinder head bolts to 30 Nm (22 ft. lbs.)

b. In sequence, torque all bolts to 45 Nm (33 ft. lbs.)

c. Install torque angle gage.
d. Calibrate gauge to zero.
e. In sequence, turn each bolt an additional 90 degrees.


For Timing Components and Front Cover installation, refer to Timing Chain service procedures. Timing Chain