637 TRACTOR-SCRAPER Starting The Engines Caterpillar

1. Move transmission control lever to NEUTRAL.

2. Turn transmission control lever safety lock to LOCK.

3. Push brake control to PARK.

4. Move hitch and bail control lever to LOCKDOWN - BAIL DOWN.

5. Move scraper controls to HOLD.

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Clear areas before moving lever.

6. Insert key and turn disconnect switch to ON.

Starting Tractor Engine (Always start tractor engine first). Above 60°F (16°C)

7. Depress accelerator to just past detent position.

8. Push in and turn HEAT-START switch to START. Release switch as soon as engine starts.

Below 60°F (16°C)

7. Depress accelerator to just past detent position.

8. Push in and turn HEAT-START switch to HEAT for indicated time (see Starting Aid Chart).

9. Push in and turn HEAT-START switch to START. Release switch as soon as engine starts. ¹

10. When engine starts it may be necessary to return HEAT-START switch to HEAT until engine runs smoothly.

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¹If engine does not start after 10 seconds, switch to HEAT for 30 seconds then start. If engine again does not start, let starter cool 2 minutes then repeat starting procedure.

Starting Scraper Engine From Tractor Above 60°F (16°C)

11. Be sure tractor engine is running smoothly and gauges read normal. Depress scraper accelerator.

12. Push in and turn HEAT-START switch to START. Release switch as soon as engine starts.

Below 60°F (16°C)

11. Be sure tractor engine is running smoothly and gauges read normal. Depress scraper accelerator.

12. Push in and turn HEAT-START switch to HEAT for indicated time (see Starting Aid Chart).

13. Push in and turn HEAT-START switch to START. Release switch as soon as engine starts. ¹

14. When engine starts it may be necessary to return HEAT-START switch to HEAT until engine runs smoothly.

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¹If engine does not start after 10 seconds, switch to HEAT for 30 seconds then start. If engine again does not start, let starter cool 2 minutes then repeat starting procedure.

Starting Scraper Engine From Scraper

11. Be sure tractor engine is running smoothly and gauges read normal. Depress tractor and scraper accelerators to 1/3engine speed.

12. Push lever to engage accelerator lock.

13. Be sure governor control lever is out of shut-off position.

14. Push in and turn HEAT-START switch to HEAT for indicated time. (see Starting Aid Chart).

15. Push in and turn HEAT-START switch to START. Release switch as soon as engine starts. ¹

16. When engine starts it may be necessary to return HEAT-START switch to HEAT until engine runs smoothly.

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¹If engine does not start after 10 seconds, switch to HEAT for 30 seconds then start. If engine again does not start, let starter cool 2 minutes then repeat starting procedure.

When Starting Fluid is Required

1. Do steps 1 through 6 on page 23. Depress accelerators to just past detent position.

2. Push in and turn HEAT-START switch to HEAT for indicated time (see Starting Aid Chart).

3. Push in and turn HEAT-START switch to START ... ... and discharge starting aid capsule or spray starting fluid sparingly into precleaner while cranking.

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Use starting fluid sparingly. Follow manufacturer's instructions carefully.

4. When engine starts it may be necessary to return HEAT-START switch to HEAT until engine runs smoothly.

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NOTICE
If engine does not start, let starter cool 2 minutes then repeat starting procedure. Never switch to HEAT when engine is warm and running.

Starting With Boost

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NOTICE
When using jumper cables be sure to connect in parallel: Negative (-) to negative (-) and positive (+) to positive (+).

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Attach ground cable last, and remove first, to prevent sparks from occurring near the battery which could cause battery vapors to explode. Attach ground cable from booster battery to a point away from, and below, the battery on the machine to be started.