C3.3 Industrial Engine Caterpillar

The cylinder head bolts are two different lengths. The following information provides the proper torque for the cylinder head bolts.

Illustration 1	g01017007
The tightening sequence

Lubricate the threads and the underside of the head bolts with clean engine oil.

Tighten the bolts in the sequence that is shown in illustration 1 to the following torque. ... 50 N·m (37 lb ft)

Tighten the bolts again to the following torque. ... 100 N·m (74 lb ft)

Illustration 2	g00905621
Head bolts

The head bolts require an additional torque turn procedure. The numbers (1, 3, 4) are three long cylinder head bolts. All the other bolts are short bolts. The tightening sequence is shown in illustration 1.

Place an index mark on the top of each bolt head. Tighten the short bolts for the additional amount. ... 225 degrees

Place an index mark on the top of each bolt head. Tighten the long bolts for the additional amount. ... 270 degrees

Thickness of the cylinder head ... 117.95 to 118.05 mm (4.643 to 4.647 inch)

Minimum thickness of cylinder head ... 117.20 mm (4.614 inch)

The maximum distortion of the cylinder head is given in table 1.

Illustration 3	g01017008
Cylinder head

Table 1

Dimension	Maximum Permissible Distortion
Width (A)	0.03 mm (0.0018 inch)
Height (B)	0.05 mm (0.0019 inch)
Diagonal Line (C)	0.05 mm (0.0019 inch)
Width (D)	0.03 mm (0.0018 inch)