MAINTENANCE PROCEDURE 4.9.3.g CHECK AND ADJUST COOLING FAN BELT TENSION CHECKING 1. The deflection should be approx. 9 to 13 mm (0.355 to 0.5 in.) when pressed at a point midway between the crank- shaft pulley and the fan pulley with a finger pressure of approx. 98 N (10 kgf). NOTE As a guideline, there is no problem if the deflection is ap- prox. 10 mm (0.5 in). ADJUSTMENT When this maintenance is carried out, it is necessary to open (tilt) the floor. Before starting the operation to open the floor refer to the explanation for each part in Section "3.2.12 METHOD OF OPENING (TILTING) FLOOR" when carrying out the operation. Or ask your Komatsu Dealer to carry out the maintenance.
Immediately after the engine is stopped, the parts and oil are at a high temperature, and will cause burns. Wait for the temperature to go down before starting the operation. Prepare a pinch bar. Prepare a wooden block. 1. When opening (tilting) the floor, see Section "3.2.12 METHOD OF OPENING (TILTING) FLOOR" - " When opening (tilt open)" for details. 2. Insert a bar between alternator (1) and the cylinder block to fix alternator (1) in position. When fixing alternator (1) in position, insert a wooden block between the bar and al- ternator (1) to prevent any damage to the alternator. 3. Loosen alternator adjustment bolt (2) and mounting bolts (3). 4.
Move alternator (1) to adjust so that the belt tension is ap- prox. 7 to 10 mm (0.276 to 0.4 in.) when pressed at a point midway between the alternator pulley and the fan pulley with a finger pressure of approx. 98 N (10 kgf). 5. Tighten adjustment bolt (2), then tighten mounting bolts (3) to secure alternator (1) in position. 6. Check for damage to the pulleys, and wear of the V- groove and V-belt. Be particularly careful to check that the V-belt is not in contact with the bottom of the V-groove. 7. If the belt is stretched, leaving no allowance for adjust- ment, or if it is cut or cracked, contact your Komatsu Deal- er for replacement. 8. After completing the adjustment, close the floor.
For de- tails, see Section "3.2.12 METHOD OF OPENING (TILT- ING) FLOOR" - " When closing (tilt close)". 200 WARNING