Caterpillar 257 - Monthly Maintenance

Engine Oil Sample - Obtain

• The sampling port for the engine oil is located on the left side of the engine block.

Belts - Inspect/Adjust/Replace

• Stop the engine in order to inspect the belt.

• Open the engine access door. Refer to Operation and Maintenance Manual, “Access Doors and Covers”.

• Remove the guard for the V-belt.

• Inspect the condition of the belt (1) and the adjustment of the belt. The belt should deflect 10 mm (0.39 inch) under a straight pull of 44 N (10 lb). This measurement should be taken between the alternator pulley and the crankshaft pulley.

• Loosen the mounting bolt (2). Loosen the adjusting locknut (3).

• Move the alternator until the correct tension is reached.

• Tighten the adjusting locknut. Tighten the mounting bolt.

• Recheck the belt deflection. If the amount of deflection is incorrect, repeat step 4 to step 7.

• Install the guard for the V-belt.

• Close the engine access door.