621B TRACTOR-SCRAPER Before Starting Caterpillar

Before Starting
1.1. Walk-Around Checks
2.1. Positioning Seat

Walk-Around Checks

For your own safety, and maximum service life of the tractor-scraper, make a thorough walk-around inspection before mounting the tractor-scraper or starting the engine. Check for such items as loose bolts, trash build-up, oil or coolant leaks, condition and inflation of tires and condition of cutting edges.

1. Check crankcase oil level. Oil level must be in SAFE STARTING RANGE on ENGINE STOPPED side of dipstick.

2. Check coolant level. Maintain level 1/2 inch (1 cm) below bottom of fill pipe.

3. Check hydraulic system oil level. Maintain level above ADD mark in sight gauge or to FULL mark on dipstick.

4. Check air cleaner service indicator. If RED piston is locked in the visible postion, have air cleaner serviced.

5. Check fuel level.

6. Check transmission oil level. Oil should show on dipstick.
7. Check tire pressures. (Refer to TIRE INFLATION INFORMATION.)
8. Check controls for free movement.

Positioning Seat

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

Fasten seat belt securely. Always check condition of seat belt. Seat adjustment must be checked at the beginning of each shift and when operators change.


NOTE: Engine must be running and driver seated well back.

1. To adjust seat position, pull lever out and hold. Slide seat forward or backward as desired. Release lever and move seat slightly to lock lever.

2. Adjust damping valve for riding comfort.
1. Move lever up for firmer ride.
2. Move lever down for softer ride.

3. For height adjustment:
1. Move lever forward to raise seat position.
2. Move lever to center detent position for mid-height position.
3. Move lever backward to lower seat position.