637 TRACTOR-SCRAPER Every 2000 Service Hours Or 1 Year Caterpillar

(50)Hydraulic Control System - Change Oil and Wash Filler Screen

1. Drive machine over a ditch so bowl cylinders can move a complete stroke. Raise the bowl and apron and move the ejector back. When oil is warm, stop the engine.

2. Remove filler cap slowly to relieve pressure.

3. Remove tank drain plug.

4. Turn drain valve and drain oil.

5. Lower bowl and apron complete stroke of cylinders. Do not use QUICK-DROP or FLOAT positions.

6. Change filter elements. (See item 39.)

7. Close drain valve.

8. Clean and install drain plug.

9. Remove snap ring and filler strainer. Wash strainer in kerosene. Install strainer.

10. Fill hydraulic tank to bottom of filler strainer. (Refill capacity on page 54.)

11. Start engine and run at low idle with controls in HOLD position.

12. Fill tank to FULL mark in sight gauge and install filler cap.

12. Move ejector forward and back 3 or 4 times. With ejector forward, add oil to FULL mark in sight gauge.

14. Raise and lower apron 3 or 4 times. Do not use FLOAT position. With apron lowered, add oil if necessary.

15. Raise and lower bowl 3 or 4 times. Do not use QUICK DROP position. With bowl down, add oil if necessary.

16. With engine running approximately 1200 RPM, move bowl, apron and ejector through 2 or 3 complete cycles.

17. Move machine to level ground.

18. Bleed filters. (See item 39.)

19. With engine at half speed, turn steering wheel one direction to completely retract one cylinder.

20. Open bleed valve on retracted steering cylinder. When oil flows free of bubbles, close valve.

21. Open valves on steering follow-up cylinder. Close valves when oil flows free of air bubbles.

22. Turn steering wheel in opposite direction. Open other steering cylinder bleed valve and steering follow-up cylinder valves. When oil flows free of air bubbles, close valves.

23. Stop engine and check oil level. Bring oil level to FULL mark in sight gauge.

24. Install new filler cap gasket. Install and tighten cap.

(51)Ejector Carrier Bearings - Repack

1. Raise ejector and block to remove weight from carrier roller.

2. Remove cover.

3. Remove cotter pin, nut and washer.

4. Remove carrier roller. Wash shaft and carrier parts in kerosene. Inspect parts for wear.

5. Apply grease to inner bearing. Install carrier roller and fill with grease.

6. Install outer bearing washer and nut.

7. Tighten nut until roller locks. Back nut off 1/6 turn (Roller must turn freely by hand.)

8. Install cotter pin, pack in grease and install cover.

9. Remove jack.

10. Repeat procedure for other carrier roller.

11. See item 61 for roller adjustment.

(52)Ejector Guide Roller Bearings - Repack

1. Remove cover.

2. Flatten lock. Remove nut, lock and washer.

3. Loosen adjusting bolt.

4. Drive shaft down.

5. Remove guide roller. Wash shaft and roller parts in kerosene. Inspect parts for wear.

6. Apply grease to lower bearing. Install guide roller and drive shaft up. Tighten adjusting bolt.

7. Fill guide roller with grease. Install upper bearing, washer, lock and nut.

8. Tighten nut until roller locks. Block nut off 1/6 turn. (Roller must turn freely by hand.)

9. Crimp lock so nut will not turn. Pack in grease and install cover.

10. Repeat procedure for other guide roller.

Adjust

1. Loosen clamp bolt.

2. Turn adjusting nut to desired position.

3. Tighten clamp bolt. Rollers are properly adjusted when the ejector operates without binding or rubbing bowl.

(53)Seat Suspension

Lubricate 3 fittings.

(54)Tachometer Drive Cable

Disconnect cable from tachometer. Pull out core and wipe off old grease. Lubricate 3/4 of core from drive end with multipurpose-type grease. Install core and cable.

(55)Tractor Engine Valve Lash

Check valves with engine stopped.

1. Remove camshaft cover.

2. Remove timing bolt and plug.

3. Turn flywheel to close No. 1 exhaust and inlet valves and ...

4. Allow timing bolt to be installed in flywheel. Do not use starting motor to turn engine.

5. Check lash for No. 1, No. 3 and No. 5 exhaust valves. Adjust if necessary.

6. Check lash for No. 1, No. 2 and No. 4 inlet valves. Adjust if necessary.

7. Remove timing bolt.

8. Rotate flywheel 360° to close No. 6 exhaust and inlet valves and ...

9. Allow timing bolt to be installed in flywheel.

10. Check lash for No. 2, No. 4 and No. 6 exhaust valves. Adjust if necessary.

11. Check lash for No. 3, No. 5 and No. 6 inlet valves. Adjust if necessary.

12. Remove timing bolt from flywheel.

13. Install timing bolt in storage hole.

14. Install plug.

15. Install camshaft cover.

Adjusting Valve Lash

1. Insert a cross point (Phillips) screwdriver into hole in side of cam follower.

2. Turn screwdriver clockwise to increase lash or counterclockwise to decrease lash.

(56)Scraper Engine Valve Lash

Check lash with engine stopped.

1. Remove valve cover.

2. Remove plug.

3. Turn flywheel to close No. 1 exhaust and inlet valve and allow bolt (Part No. L2070) to be installed in flywheel. Turn engine slowly when installing bolt. Do not use starting motor.

4. Check No. 1, No. 3 and No. 5 exhaust valves. Adjust if necessary. (See page 39.)

5. Check No. 1, No. 2 and No. 4 inlet valves. Adjust if necessary.

6. Remove bolt.

7. Turn flywheel 360° to close No. 6 exhaust and inlet valves and ...

8. Allow bolt to be installed in flywheel.

9. Check No. 2, No. 4 and No. 6 exhaust valves. Adjust if necessary. (See page 39.)

10. Check No. 3, No. 5 and No. 6 inlet valves. Adjust if necessary. (See page 39.)

11. Remove bolt.

12. Install plug.

13. Start engine.

14. With engine at low idle check valve rotators, if a valve does not rotate see your AVSpare dealer.

15. Stop engine and install valve cover. Tighten bolts to 6-10 lb. ft. (0,83-1,39 mkg) in the following sequence.

Adjusting Valve Lash

1. Loosen locknut.

2. Turn adjusting screw.

3. Check adjustment.

4. Tighten locknut.

5. Recheck adjustment.

6. Remove bolt.

When Required

(57)Air Intake Systems - Tractor

Servicing Primary Elements

Service filter elements when RED band locks in the visible position.

1. Remove covers and primary elements.

2. Clean inside of air cleaner body.

Never service air cleaner elements with engine running.

3. Clean and inspect elements. See page 44.

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NOTICE
Always inspect primary element before and after cleaning with a light bulb inside element. Discard if any tears, rips or damage is evident.

4. Install clean elements and covers.

5. Reset filter indicator.

If indicator shows RED shortly after installation of a primary element which has been cleaned approximately 6 times, change to another clean element.

NOTE: The primary element should be replaced after being cleaned a maximum of 6 times. Replace the element once a year even though it has not been cleaned 6 times.

If indicator still shows RED shortly after the installation of the clean primary element, change the secondary element.

Replace the secondary element at the time the primary element is cleaned for the fourth time.

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NOTICE
Always replace the secondary element. Do not attempt to reuse by cleaning.

Servicing Secondary Element

1. Remove covers and primary elements.

2. Remove secondary elements.

3. Cover air inlet openings and clean inside of air cleaner body.

4. Discard used elements.

5. Inspect precleaner, dust ejector and exhaust venturi. Clean all parts when necessary.

6. Clean all parts with compressed air, a stiff fiber brush or wash in water and non-sudsing detergent. Dry all parts before installation.

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

7. Uncover air inlet openings.

8. Install secondary elements. Tighten nuts to 20 ± 5 lb. ft. (2,8 ± 0,7 mkg).

9. Install primary elements and covers.

10. Reset filter indicator.

Never use elements with damaged pleats, gaskets or seals.

Have spare elements on hand to use while cleaning and drying used elements.

Scraper

Servicing Primary Element

Service filter elements when RED band locks in the visible position.

1. Remove wing nuts and cover.

2. Remove primary element and clean inside of air cleaner body.

3. Clean and inspect elements. See page 44.

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NOTICE
Always inspect primary element before and after cleaning with a light bulb inside element. Discard if any tears, rips or damage is evident.

4. Install clean elements and covers.

5. Reset filter indicator.

If indicator shows RED shortly after installation of a primary element which has been cleaned approximately 6 times, change to another clean element.

NOTE: The primary element should be replaced after being cleaned a maximum of 6 times. Replace the element once a year even though it has not been cleaned 6 times.

If indicator still shows RED shortly after the installation of the clean primary element, change the secondary element.

Replace the secondary element at the time the primary element is cleaned for the fourth time.

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NOTICE
Always replace the secondary element. Do not attempt to reuse by cleaning.

Servicing Secondary Element

1. Remove cover and primary element.

2. Remove secondary element.

3. Cover air inlet opening and clean inside of air cleaner body.

4. Discard used elements.

5. Inspect precleaner, dust ejector and exhaust venturi. Clean all parts when necessary.

6. Clean all parts with compressed air, a stiff fiber brush or wash in water and non-sudsing detergent. Dry all parts before installation.

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

7. Uncover air inlet opening.

8. Install secondary element. Tighten nuts to 20 ± 5 lb. ft. (2,8 ± 0,7 mkg).

9. Install primary element and cover.

10. Reset filter indicator.

Never use elements with damaged pleats, gaskets or seals.

Have spare elements on hand to use while cleaning and drying used elements.

Cleaning Air Cleaner Elements

Pressure Air - 30 PSI (2 kg/cm²) Maximum

1. Direct air inside element along length of pleats.

2. Direct air outside along length of pleats. Direct air inside along length of pleats. Check element.

Water - 40 PSI (3 kg/cm²) Maximum

1. Direct water inside element along length of pleats.

2. Direct water outside along length of pleats. Rinse, air dry thoroughly and check.

Detergent

1. Wash in warm water and nonsudsing household detergent.

2. Rinse with clean water, 40 PSI max (3 kg/cm²), see above.

3. Air dry thoroughly and check.

Checking Element

1. Insert light inside clean and dry element and check. Discard element if tears or rips are found.

2. Wrap and store good elements in a clean dry place.

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

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NOTICE
Do not clean elements by bumping or tapping. Do not use elements with damaged pleats, gaskets or seals.

NOTE: Have spare elements on hand to use while cleaning used elements.

(58)Tractor Fuel System Filters

Primary Fuel Filter - Clean When Fuel Pressure Gauge Registers Out

1. Remove cover.

2. Remove element and wash in clean kerosene.

3. Dry with pressure air and install.

Final Fuel Filter - Change if Fuel Pressure Gauge Still Registers OUT with Engine Running.

1. Remove the used filters.

2. Clean gasket surfaces and lubricate filter gasket with diesel fuel.

3. Install new filters and hand tighten. Prime fuel system and start engine. Check for leaks.

Priming the Fuel System

1. Open filter housing vent valve.

2. Unlock priming pump.

3. Operate plunger until ...

4. Flow of fuel from drain line is free of air bubbles.

5. Close vent valve and lock priming pump.

(59)Scraper Fuel System Filters

Primary Fuel Filter - Clean When Fuel Pressure Gauge Registers Out

1. Remove element.

2. Wash in clean kerosene or diesel fuel.

3. Install element.

Drain Final Fuel Filter

1. Open vent valve.

2. Remove drain plug.

3. Drain water and sediment.

4. Install drain plug.

5. Close vent valve.

6. Prime the fuel system. (See page 48.)

Final Fuel Filter - Change if Fuel Pressure Gauge Still Registers Out with Engine Running.

1. Remove drain plug.

2. Drain filter.

3. Remove filter.

4. Clean gasket surface.

5. Lubricate gasket surface with diesel fuel.

6. Install new filter.

7. Tighten until gasket surface touches base, then tighten additional 1/2 turn.

8. Prime the fuel system. (See page 48.)

9. Start engine and check for leaks.

Priming The Fuel System

1. With engine stopped, open vent valve.

2. Unlock priming pump.

3. Operate pump.

4. Pump until fuel flows free of air bubbles.

5. Close pump.

7. Lock pump.

8. Close vent valve.

9. Start engine.

(60)Cooling Systems

Whenever draining and refilling the cooling system, always recheck the coolant level when the engine reaches normal operating temperature. Remove cap and maintain coolant level 1/2" (1 cm) below the bottom of the fill pipe.

Check specific gravity of antifreeze solution frequently in cold weather to assure adequate protection.

Never add coolant to an overheated engine. Allow engine to cool first.

Add AVSpare Rust Inhibitors to coolant except when using permanent-type antifreeze containing rust inhibitors.

Use clean water that is low in scale forming minerals - not softened water.

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Inhibitor contains alkali, avoid contact with skin and eyes.

Cleaning Cooling Systems

1. Run engines until temperature gauge registers NORMAL. Park machine on level ground and stop engine.

2. Turn filler caps slowly to relieve pressure, then remove caps.

3. Open radiator drain valves and drain coolant.

4. Close drain valves. Fill systems with cleaning solution. ⁽¹⁾

5. Start and run engines for 1/2hour.

6. Stop engines and drain cleaning solution.

7. Flush systems with clean water until draining water is clear.

8. Close drain valves. Fill systems with neutralizing solution. ⁽²⁾

9. Start and run engines for 10 minutes.

10. Stop engines and drain neutralizing solution.

11. Flush systems with clear water.

12. Close drain valves. Add coolant to proper level. Recheck coolant levels when engines are at normal operating temperature.

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⁽¹⁾2 lb. Sodium Bisulphate (NaHSO₄) per 10 gal. water (25 grams per liter).

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⁽²⁾1/2 lb. Sodium Carbonate Crystals (Na₂CO₃, 10 H₂O) per 10 gal. water (6 grams per liter).

NOTE: Most commercial cooling system cleaners may be used.

NOTE: If machine is to be stored in or shipped to an area with below freezing temperatures, the cooling system must be drained completely or protected to lowest expected ambient temperature.

(61)Ejector Rollers - Adjust

1. Loosen clamp bolts.

2. Turn adjusting nuts to desired positions.

3. Tighten clamp bolt. Rollers are adjusted when the ejector operates without binding or rubbing bowl.

(62)Cutting Edges

1. Raise and block bowl and apron. Stop engine.

2. Remove bolts.

3. Remove section and clean contact surfaces.

4. Use opposite edge if not worn. If both edges are worn, change section.

5. Install bolts and tighten to 900 ± 50 lb. ft. (124,5 ± 70 mkg).

6. Start engine and remove blocks.

7. After a few hours of operation, retighten bolts.

(63)Routing Bits

1. Raise and block bowl and apron. Stop engine.

2. Remove bolts.

3. Remove routing bit and clean contact surfaces.

4. Use other end of bit if not worn. If both ends are worn, change bit.

5. Install bolts and tighten.

6. Start engine and remove blocks.

7. After a few hours of operation, retighten bolts.

(64)Hydraulic Cylinder - Shim adjusted rod packing

1. Lower bowl and apron and stop engine.

2. Relieve hydraulic pressure by moving controls with engine stopped.

3. Remove bolts holding gland to cylinder head.

4. Pry or lightly tap gland to remove.

5. Cut and remove one shim.

6. Assemble and test cylinder for leaking.

7. If still leaking remove one more shim. Do not remove more than two shims.

8. Assemble and test for leaking.

9. If still leaking install new packing. See your AVSpare dealer.