C3.3 Industrial Engine Caterpillar

Illustration 1	g01277351
Checking the end play of the camshaft

(1) End play of a new camshaft ... 0.10 to 0.55 mm (0.004 to 0.022 inch)

Maximum permissible end play of a worn camshaft ... 0.60 mm (0.023 inch)

Illustration 2	g01277354
Typical camshaft

(2) Bolt

Tighten the bolt to the following torque. ... 95 N·m (70 lb ft)

(3) Camshaft thrust washer

Thickness of the thrust washer ... 5.486 to 5.537 mm (0.2160 to 0.2180 inch)

Depth of the recess in the cylinder block for the thrust washer ... 5.560 to 5.640 mm (0.2189 to 0.2220 inch)

Tolerance of the thrust washer in cylinder block front face ... −0.154 to −0.023 mm (−0.0061 to −0.0009 inch)

(4) The diameters of the camshaft journals are given in the following table.

Maximum wear on the camshaft journals ... 0.05 mm (0.0021 inch)

Illustration 3	g01345411
Typical example

(5) Camshaft lobe lift

Naturally aspirated

Inlet lobe ... 7.382 to 7.482 mm (0.2906 to 0.2946 inch)

Exhaust lobe ... 7.404 to 7.504 mm (0.2915 to 0.2954 inch)

Turbocharged engines and turbocharged aftercooled engines

Inlet lobe ... 7.266 to 7.366 mm (0.2861 to 0.2900 inch)

Exhaust lobe ... 8.081 to 8.181 mm (0.3181 to 0.3221 inch)

(6) Camshaft lobe height

(7) Base circle

To determine the lobe lift, use the procedure that follows:

1. Mount the camshaft between centers.

2. By using a dial indicator in contact with the surface of the lobe, rotate the camshaft and record the maximum and minimum lift.

   Note: There may be two lobes on the camshaft. Refer to illustration 3. The surface between the lobes may not return to the radius of the base circle. Using a micrometer to measure the diameter of the base circle may give a inaccurate result.

3. Subtract the smallest dimension from the largest dimension. The difference is the actual camshaft lobe lift.

Maximum permissible deviation between the actual lobe lift and the specified lobe lift of a new camshaft ... 0.05 mm (0.002 inch)