J621 TRACTOR-SCRAPER Every 500 Service Hours Or 3 Months Caterpillar

(27)Hydraulic System

1. Lower bowl and close ejector floor. Stop engine. Move scraper controls to relieve pressure.

2. Loosen filler cap slowly to relieve pressure.

3. Remove hydraulic system filter cover, elements and screen.

4. Wash screen in clean solvent and install new elements.

5. Install cover and tighten to 43 ± 4 lb. ft. (5,9 ± 0,6 mkg). Start engine.

6. Open filter bleed plug.

7. Close bleed plug when oil flows without air bubbles. Check oil level. Add oil if necessary.

(28)Transmission System

1. Remove filter housing drain plug.

2. Remove cover and element. Clean housing.

3. Remove element from cover. Inspect seals. Install new seals if necessary.

4. Install new element. Tighten to 10 ± 2 lb. ft. (1,5 ± 0,5 mkg).

5. Install cover.

6. Clean and install filter housing drain plug. Tighten to 35 ± 5 lb. ft. (4,8 ± 0,7 mkg).

7. Remove magnetic strainer drain plug.

8. Remove cover.

9. Remove screen and magnets

10. Remove magnets from screen and wash both in clean solvent.

11. Clean magnets with a soft cloth, stiff brush or compressed air. Do not drop or jar magnets.

12. Install screen and magnets as a unit with small end of tube out. Be sure screen is piloted on the tube.

13. Inspect seals. Use new seals if necessary.

14. Install cover.

15. Clean and install drain plug.

16. Start engine and operate machine a few minutes.

17. Check oil level and add oil if necessary.