C3.4 Engines for Caterpillar Built Machines Caterpillar

Illustration 1	g00988290

(1) End play of a new camshaft ... 0.10 ± 0.25 mm (0.0039 ± 0.0098 inch)

Maximum permissible end play of a worn camshaft ... 0.30 mm (0.0118 inch)

(2) Tighten the thrust plate bolts to the following torque. ... 10 to 13 N·m (7 to 10 lb ft)

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

Illustration 2	g01353497
Typical example

(A) Camshaft lobe lift

Naturally aspirated engines

Inlet lobe ... 6.722 mm (0.2646 inch)

Exhaust lobe ... 6.720 mm (0.2645 inch)

Turbocharged engines

Inlet lobe ... 6.682 mm (0.2631 inch)

Exhaust lobe ... 6.722 mm (0.2646 inch)

The service limit for camshaft lobe lift is given below:

Naturally aspirated engines

Inlet lobe ... 6.222 mm (0.2450 inch)

Exhaust lobe ... 6.220 mm (0.2449 inch)

Turbocharged engines

Inlet lobe ... 6.182 mm (0.2434 inch)

Exhaust lobe ... 6.222 mm (0.2450 inch)

(B) Camshaft lobe height

(C) Base circle

(D) Lift for second camshaft lobe

Inlet valve for turbocharged engines

55 kW ... 0.923 mm (0.0363 inch)

62 kW ... 1.108 mm (0.0436 inch)

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

1. Measure the camshaft lobe height (B) .

2. Measure the base circle (C) .

3. Subtract the base circle that is found in Step 2 from the camshaft lobe height that is found in Step 1. The difference is the camshaft lobe lift.

If the camshaft lobe lift is less than the service limit, replace the camshaft.

Illustration 3	g01014070

(4) Camshaft

Deflection over the full length of the camshaft

Maximum at assembly ... 0.02 mm (0.0008 inch)

Repair limit ... 0.05 mm (0.0020 inch)