641B & 651B TRACTOR-SCRAPERS Every 500 Service Hours Or 3 Months Caterpillar

Every 500 Service Hours Or 3 Months
1.1. (18)Hydraulic System
2.1. (19)Transmission System
3.1. (20)Tractor And Scraper Brake Camshafts
4.1. (21)Engine Crankcase

(18)Hydraulic System


Machine level, scraper lowered, ejector forward, parking brake set and engine stopped.

Move hydraulic controls to help relieve pressure.

1. Remove housing drain plug.

2. Remove cover and used element. Wash cover with clean solvent.

3. Inspect cover seal. Install new seal if necessary.
4. Clean housing and install new element.
5. Install cover.
6. Clean and install drain plug.

7. Remove steering filter cover, element and screen.

8. Remove scraper filter cover, elements and screen.
9. Wash screens in clean solvent.
10. Allow to dry.
11. Install new elements and cleaned screens.

12. Install covers.
13. Start engine and run at low idle to fill filters.
14. Check for leaks.

15. Stop engine and check oil level.

16. Add oil if necessary.

(19)Transmission System

1. Remove filter drain plug.

2. Remove cover and used element. Clean filter housing.
3. Remove element and wash cover with clean solvent.
4. Inspect seals. Use new seals if necessary.
5. Install element.

6. Coat seals with clean oil.
7. Install cover and element carefully to avoid damage to seals.
8. Clean and install drain plug.

9. Remove cover.

10. Remove screen and magnets.
11. Wash screen and magnets in clean solvent. Clean magnets with a cloth, stiff brush or pressure air.

------ WARNING! ------

When using pressure air, wear safety glasses and protective clothing. Use 30 PSI (2 kg/cm2) maximum pressure air for cleaning purposes.



Do not drop or rap magnets against hard objects. Replace any damaged magnets.

12. Install screen and magnets.

13. Inspect cover seal. Use new seal if necessary. Install cover.
14. Fill compartment until oil shows on dipstick.
15. Start engine and run at low idle to warm the oil and fill drained housings.
16. Check for leaks.
17. Check oil level. Maintain oil level to FULL mark on dipstick.

(20)Tractor And Scraper Brake Camshafts

Lubricate 2 fittings each wheel. Total 8 fittings.

(21)Engine Crankcase

1. Loosen hose clamp. Remove cover assembly and element.
2. Wash cover and element in clean solvent.
3. Install element and cover.