NO. 112, 120 & 140 MOTOR GRADERS Every 500 Service Hours Or 3 Months Caterpillar

(28)Engine Crankcase And Flywheel Clutch - Change Oil and Filter Element (112 and 120)

1. Oil should be warm, machine level and engine stopped. Remove crankcase filler plug and drain plug. Allow oil to drain.

2. Open clutch compartment drain valve. Allow oil to drain.

3. Remove filter drain plug. Allow oil to drain.

4. Loosen filter housing bolt and remove housing and filter.

5. Clean filter housing, base and drain plug. Install new element in housing.

6. Install new O-ring seal. Install housing and element on base. Install plug.

7. Clean and install crankcase drain plug.

8. Close clutch compartment valve.

9. Fill crankcase to Full on engine stopped side of gauge (refill capacity on page 44).

10. Install filler plug. Run engine for 2 minutes. Check oil with engine running. Maintain level to FULL mark on engine running side of gauge.

(29)Engine Crankcase Breather - Wash

1. Disconnect breather hose.

2. Loosen mounting bolt and remove breather. Wash in kerosene.

3. Inspect seal. Replace if necessary.

4. Install breather and connect hose.

(30)Power Control Worm And Gear Housing - Check Oil

1. Filler plug is located to right of clutch pedal.

2. Oil should be visible in filler elbow.

(31)Steering Gear Housing

Maintain oil level to bottom of level plug opening of manual type. Maintain level 1-1/2inches (38 mm) below opening in hydraulic type.

(32)Wheel Lean

Maintain oil level to bottom of filler opening.

(33)Transfer Gear

Maintain oil level to bottom of filler opening.

(34)Circle Reverse

Maintain oil level to bottom of filler opening.

(35)Power Control

Maintain oil level to bottom of level plug opening. Fill plug is at top right.

(36)Tandem Drive Housings

1. Maintain oil level to bottom of level opening. One housing each side.

2. Fill through cover plate opening on top.

3. Remove one breather each housing and wash in kerosene. Blow or shake dry.

4. Oil elements lightly and install breathers.

140 Only

1. Check oil level in each tandem. Oil should be to FULL.

2. Remove element retaining nut.

3. Remove element.

4. Wash element in clean kerosene.

5. Wash gauge assembly.

6. Be sure vent in gauge assembly is open.

7. Assemble parts. Oil element lightly and install gauge.

(37)Transmission And Rear Axle Housing - Change Filter Element and Wash and Oil Breather

1. Remove housing drain plug.

2. Remove filter cover and filter element.

3. Clean housing and cover assembly. Use new gasket if necessary. Use new element.

4. Install element and cover assembly. Clean and install drain plug.

5. Remove breather located at front of engine compartment.

6. Wash in kerosene and blow or shake dry. Oil element lightly and install breather.