D379, D398, D399 INDUSTRIAL AND GENERATOR SET ENGINES Caterpillar

(15)Fuel System-Drain Fuel Filter Housing

1. Close the fuel supply valve if the fuel tank is located above the level of the fuel filters.

2. Remove the drain plug from one cover of the fuel filter housing. Drain water and sediment from the filter housing.

3. Install the drain plug.

4. Remove the drain plug from the other cover of the fuel filter housing.

5. Drain water and sediment from that end.

6. Install the drain plug and vent plug.

7. Prime the fuel system.

(16)Alternator Belts

1. Inspect the belts for wear.

When belt replacement is necessary, belts must be replaced in complete matched sets. Never replace only one belt. The new belt will carry all the load and fail rapidly.

2. Apply a 25 pound (110 N) force perpendicular to the belt, midway between the driving and driven pulley. Measure the belt deflection.

Proper belt deflection is 9/16 to 13/16" (15 to 20 mm). Adjust the belt tension as required.

To Adjust Alternator Belts

1. Remove the belt guard.

2. Loosen the locknut on the belt tightener rod.

3. Turn the adjustment nut until correct belt deflection is obtained.

4. Tighten the locknut.

5. Check the belt adjustment.

6. Install the belt guard.