Hyster K005 (H80XM) Forklift Service Repair Manual

SERVICE REPAIR H70XM H80XM H90XM H100XM H110XM H120XM [K005]

1800 SRM 734

Description and Operation

General This section has a description and the repair procedures for the parts of the hydraulic brake system. These parts include the brake booster, master cylinder, and brake shoe assemblies.

Description and Operation The brake pedal is connected to the push rod for the brake booster. The brake booster helps increase the force on the master cylinder by using vacuum from the engine. The piston in the master cylinder forces oil to the wheel cylinders to apply the brakes. (The system allows braking without vacuum from the engine.)

the piston pushes fluid through the check valve. A return spring pushes the piston back to the stop plate when the pedal is released. Fluid can flow through passages in the piston and past the primary cup as the piston returns. Fluid flows across the piston to prevent a vacuum while fluid returns through the check valve. When the piston passes the compensator port, excess fluid from the system can return to the reservoir. The check valve keeps a very small amount of pressure in the brake system.

The reservoir for brake fluid has a sending unit for a low fluid level warning light.

SERVICE BRAKE ASSEMBLY

1.

2.

3.

4.

PUSH ROD BRAKE BOOSTER RESERVOIR MASTER CYLINDER

5. OUTLET TO WHEEL CYLINDERS 6. ENGINE VACUUM CONNECTION

Figure 1. Brake Booster and Master Cylinder

BRAKE BOOSTER AND MASTER CYLINDER The brake booster and master cylinder are assembled as a unit. The brake booster has a diaphragm that is actuated by engine vacuum. See Figure 1.

The diaphragm, along with the operator’s effort, pushes on the piston in the master cylinder. Hydraulic pressure actuates the wheel cylinders as

A service brake assembly is installed at each end of the housing for the drive axle. Each service brake assembly has a single-wheel cylinder at the top of each back plate. The support plate has an anchor for each shoe. When the wheel cylinder is actuated by fluid pressure from the master cylinder, the shoes expand against the drum. The primary shoe starts to turn with the drum. This action pushes the secondary shoe tight against the drum and the anchor. When the lift truck is traveling in reverse, the primary shoe is pushed against the anchor and the drum by the secondary shoe.

The automatic adjusting linkage turns the adjuster screw wheel to adjust the clearance between the brake shoes and the brake drum. The secondary shoe and the links move with the drum during a stop when the truck is traveling in reverse. The links permit the adjuster spring lever to rotate the adjuster screw wheel. The adjuster screw wheel only can turn when there is clearance between the lining and the brake drum. The adjuster screw wheel can be turned manually through a slot in the back plate.

1

Brake Shoe Assemblies Repair

PARKING BRAKE The parking brake uses the service brake shoes.

Additional linkage pushes the shoes apart when the hand lever pulls the cables. A switch on the right-hand side of the mounting bracket is actuated by the hand lever. On all units, the switch energizes the seat warning circuit when the hand lever

1800 SRM 734 is released. On units with a MONOTROLÂŽ pedal, this switch puts the transmission in NEUTRAL by de-energizing the direction solenoids. On units with a MONOTROL pedal, there is also a switch on the left-hand side of the bracket. This switch prevents the engine from starting unless the parking brake is applied.

Brake Shoe Assemblies Repair REMOVE AND DISASSEMBLE WARNING Brake linings can contain dangerous fibers.

Breathing the dust from these brake linings is a cancer or lung disease hazard. Do not create dust! Do not clean brake parts with compressed air or by brushing. Use vacuum equipment approved for brake dust or follow the cleaning procedure in this section. When the brake drums are removed, do not create dust.

Do not sand, grind, chisel, hammer, or change linings in any way that will create dust. Any changes to linings must be done in a restricted area with special ventilation. Protective clothing and a respirator must be used.

1. Tilt the mast back, and put blocks under the outer mast weldment. Tilt the mast forward to raise the tires from the floor.

WARNING Completely remove the air from the tires before removing them from the lift truck. Air pressure in the tires can cause the tire and wheel parts to explode, causing serious injury or death.

2. Make sure that you remove all the air pressure from the tires before you remove the wheels from the hub. Remove the wheel nuts; then remove the wheels. Put capscrews (16 mm) in the threaded holes to push the brake drums from the hubs. See Figure 2 and Figure 3.

3. Remove the capscrews that the hold the axle shaft to the hub. Remove the axle shaft.

2

4. Remove the lock nut, lock plate, and bearing adjustment nut from the axle housing. Remove the outer bearing cone. Remove the hub from the axle housing. Remove the inner seals and bearing cone from the hub.

WARNING When the brake shoes are removed, do not create dust in the air. See the cleaning procedures in this section.

5. Turn the adjuster screw to loosen the brake shoes. Disconnect the linkage for the automatic adjuster.

6. Use spring pliers to remove the shoe return springs.

7. Remove the holddown springs.

CAUTION The adjuster screw assemblies are not the same. Make sure that each assembly has identification for installation on the correct side of the axle.

8. Remove the brake shoes from the wheel cylinder rods. Remove the adjuster screw spring. Remove the adjuster screw assembly.

9. Remove the parking brake cable from the lever.

Remove the lever from the brake shoe.

10. Disconnect and put a cap on the line to the wheel cylinder. Remove the backplate and shield. Remove the capscrews that hold the wheel cylinder to the backplate. Remove the cable clamp and pull the cable through the backplate.

1800 SRM 734

Brake Shoe Assemblies Repair

NOTE: LEFT-HAND SIDE SHOWN. 1.

2.

3.

4.

5.

SHIELD BACKPLATE PARKING BRAKE CABLE WHEEL CYLINDER RETURN SPRING

6.

7.

8.

9.

10.

BRAKE SHOE PIVOT SPRING SPRING GUIDE ADJUSTER LINK

11.

12.

13.

14.

15.

PIN SPRING CONNECTOR ADJUSTER PARKING BRAKE LEVER

Figure 2. Service Brakes H3.50-4.00XMS (H70-90XM)

CLEAN 1. Do not release brake lining dust from the brake linings into the air when the brake drum is removed.

2. Use a solvent approved for cleaning of brake parts to wet the brake lining dust. Follow the instructions and cautions of the manufacturer for the use of the solvent. If a solvent spray is used, do not create dust with the spray.

3

Brake Shoe Assemblies Repair

1800 SRM 734

CAUTION Do not use an oil solvent to clean the wheel cylinder. Use a solvent approved for cleaning of brake parts. Do not permit oil or grease in the brake fluid or on the brake linings.

3. When the dust is wet, clean the parts. Put any cloth or towels in a plastic bag or an airtight container while they are still wet. Put a DANGEROUS FIBERS warning label on the plastic bag or airtight container.

NOTE: LEFT-HAND SIDE SHOWN. 1.

2.

3.

4.

5.

6.

7.

SHIELD BACKPLATE PARKING BRAKE CABLE WHEEL CYLINDER LINK RETURN SPRING BRAKE SHOE

8.

9.

10.

11.

12.

13.

14.

WASHER RETAINER SPRING GUIDE PIN SPRING LINK PIVOT SPRING LINK

15.

16.

17.

18.

19.

CONNECTOR ADJUSTER SPRING ADJUSTER LEVER ADJUSTER PARKING BRAKE LEVER

Figure 3. Service Brakes H4.00XM-5.50XM (H100-120XM)

4

1800 SRM 734 4. Any cleaning cloths that will be washed must be cleaned so that fibers are not released into the air.

INSPECT

Brake Shoe Assemblies Repair 2. Use a sealant (Hyster Part No. 264159) between the backplate and the axle hanger. Install the shield and backplate. Using the sequence shown in Figure 4, tighten the capscrews to 340 to 375 N•m (250 to 275 lbf ft).

WARNING Cleaning solvents can be flammable and toxic and can cause skin irritation. When using cleaning solvents, always follow the recommendations of the manufacturer.

1. Clean all metal parts except the linings and the wheel cylinder with solvent.

2. Check the bore of the wheel cylinder for holes or scratches. Replace the wheel cylinder if there is any damage.

3. Check the return springs for damage. Inspect the backplate for wear where the brake shoes touch the backplate.

4. Inspect the brake shoes for cracks or damage. If the linings or shoes are worn or damaged, replace the brake shoes. It is recommended that brake shoes be replaced in complete sets.

5. Check the adjuster screw wheel for wear. Make sure the adjuster screw turns. Check for bent or broken adjuster links.

WARNING The brake shoes on both wheels must be replaced if any shoe is damaged. The brake performance on both ends of an axle must be equal or the lift truck can be difficult to steer when the brakes are applied.

NOTE: If the brake drums require grinding, do not grind more than 1.5 mm (0.060 in.) from the diameter. The maximum inside diameter of the brake drum, including wear, is 319.5 mm (12.58 in.). If the brake drum is larger than this, replace the brake drum.

6. Inspect the brake drums for cracks or damage.

Use sandpaper to clean the surface for the brake shoes.

ASSEMBLE AND INSTALL 1. Install the wheel cylinder on the backplate. Push the parking cable through the backplate and fasten the clamp. See Figure 2 and Figure 3.

Figure 4. Backplate Installation 3. Connect the brake line to the fitting on the wheel cylinder.

4. Install the link pivot on the rear shoe. Install the parking brake lever on the front shoe. Install the anchor pins in the support flange so that they engage the brake shoes.

5. Lubricate the back plate with a small amount of grease where the brake shoes touch. Install the brake shoes on the anchor and engage the push rods of the wheel cylinder. Engage the parking brake lever in the slot in the parking brake cable as the brake shoes are installed on the back plate.

6. Put an anchor pin that holds the brake shoes through the back plate. Put a spring seat, spring, and retainer on the anchor pin. Push the retainer onto the anchor pin and rotate the retainer 90 degrees. Make sure the retainer is in the correct position. Install another retainer spring assembly.

7. Install the link, parking brake, and spring between the parking brake lever and the brake shoe.

8. H4.00XM-5.50XM (H100-120XM): Using the correct tools, install the return springs.

9. H3.50-4.00XMS (H70-90XM): Install the anchor guide on the anchor. Install the pivot plate on its anchor.

5

Brake Shoe Assemblies Repair 10. H3.50-4.00XMS (H70-90XM): Lubricate the adjuster cable where it slides in the pivot plate groove.

11. H3.50-4.00XMS (H70-90XM): Fasten the link to the adjuster wheel actuator and put the cable around the pivot plate. Raise the adjuster wheel actuator against the spring tension and connect the link to the anchor.

CAUTION Be sure to install the white return spring first and then the black return spring. See Figure 5.

Improper assembly can result in brake failure and/or component damage.

1800 SRM 734 12. H3.50-4.00XMS (H70-90XM): Using the correct tools, install the return springs as follows: a. Install the white spring. b. Install the black spring.

13. H3.50-4.00XMS (H70-90XM): Verify that the return springs are properly installed as shown in Figure 5.

14. Connect the cable for the parking brake to the lever.

Figure 5. Proper Installation of Return Springs

6

1800 SRM 734

Brake Shoe Assemblies Repair Legend for Figure 5

NOTE: H3.50-4.00XMS (H70-90XM) RETURN SPRINGS SHOWN. 1. WHITE SPRING

2. BLACK SPRING

WARNING The threads of the adjuster wheel are not the same for each side. If the adjuster assemblies are installed on the wrong side, the brake shoe clearance will increase each time the brakes are applied. The adjuster wheel for the right brake has right-hand threads. The adjuster wheel for the left brake has left-hand threads.

15. Lubricate the adjuster screw with antiseize compound. Turn the adjuster screw in so that the brake shoes retract. Install the adjuster between the shoes. Align the adjuster screw wheel with the slot in the backplate. Install the adjuster spring with the long hook toward the adjuster screw wheel.

16. H4.00XM-5.50XM (H100-120XM): Install the adjuster spring lever and the two links.

CAUTION Do not damage the seals when you install the hub assembly.

17. Use new oil seals. Install the inner seal, the bearing cups, and the outer seal in the hub. Install the inner bearing cone on the spindle. Lubricate the inner bearing with grease. See Figure 6.

18. Install the hub on the spindle. See Figure 6. Lubricate the outer bearing cone with 80W-90 oil for gears. Install the outer bearing cone and the adjustment nut. Tighten the adjustment nut to 200 to 225 N•m (148 to 166 lbf ft) while you rotate the hub. Loosen the nut until the hub rotates freely with NO end play. The torque must be less than 27 N•m (20 lbf ft). Tighten the nut to 34 N•m (25 lbf ft) or to the first alignment position after 34 N•m (25 lbf ft). Install the lockwasher to hold the nut. Install the lock nut and tighten it to 135 to 150 N•m (100 to 111 lbf ft).

19. Install the brake drum and adjust the brake shoes as described in Brake Shoes Adjustment.

1.

2.

3.

4.

5.

6.

7.

8.

AXLE SHAFT LOCK NUT LOCK PLATE LOCK NUT OUTER BEARING HUB ASSEMBLY BEARING CUP INNER SEAL

9.

10.

11.

12.

13.

14.

BEARING CUP INNER BEARING OUTER SEAL BRAKE DRUM SHIELD PARKING BRAKE CABLE

Figure 6. Brake and Hub Assembly 20. Apply sealant (Hyster Part Number 264159) to the flange of the axle shaft. Install the axle shaft.

Tighten the capscrews to 225 to 250 N•m (166 to 184 lbf ft). See Figure 7.

CAUTION When the wheels have been installed, check all wheel nuts after 2 to 5 hours of operation.

Tighten the nuts to the correct torque. When the nuts stay tight after an 8-hour check, the interval for checking can be extended to 500 hours.

21. Install the wheel. Tighten the wheel nuts to 610 to 680 N•m (450 to 500 lbf ft) on all units.

7

Brake Booster and Master Cylinder Repair

1800 SRM 734

22. Remove the air from the brake system and adjust the brakes. See Brake Shoes Adjustment in this section.

Figure 7. Axle Shaft Tightening Sequence

Brake Booster and Master Cylinder Repair REMOVE

3. Remove seals from the piston.

1. Disconnect the push rod from the brake pedal.

See Figure 8. Disconnect the brake line at the master cylinder. Cover the end of the brake line.

Disconnect the wires at the reservoir.

CLEAN AND INSPECT

2. Remove the nuts that hold the brake booster to the mount.

3. Remove the brake booster and master cylinder.

DISASSEMBLE NOTE: Do not disassemble the brake booster. Repair parts are not available.

1. Remove the nuts that hold the master cylinder to the brake booster. See Figure 9.

WARNING There is a compressed spring behind the piston. Be careful when removing the snap ring and piston.

2. Remove the snap ring from the end of the master cylinder. Carefully remove the piston and spring from the bore.

8

CAUTION DO NOT use an oil solvent to clean the master cylinder. Use a solvent approved for cleaning of brake parts.

Inspect the bore of the master cylinder for holes or scratches. Replace the master cylinder assembly if there is damage.

ASSEMBLE NOTE: Lubricate the parts of the master cylinder with clean brake fluid.

1. Install the seals on the piston. Install the seat, check valve, and spring in the bore. Install the spring and piston. Install the snap ring in the bore. See Figure 9.

2. Install the O-ring and master cylinder on the brake booster.

Thank you very much for your reading. Please Click Here Then Get More Information.

NOTE: If there is no response to click on the link above, please download the PDF document first and then click on it.

1800 SRM 734

1.

2.

3.

4.

RETURN SPRING BRAKE PEDAL INCHING SPOOL LINK INCHING LINK

Brake Booster and Master Cylinder Repair

5.

6.

7.

8.

INCHING CRANK BRAKE BOOSTER/MASTER CYLINDER BRAKE SWITCH BRACKET

Figure 8. Brake System Arrangement

9

Brake Booster and Master Cylinder Repair

1.

2.

3.

4.

5.

6.

7.

8.

9.

BRAKE BOOSTER SNAP RING SEAL PISTON SPRING CHECK VALVE SEAT O-RING MASTER CYLINDER

1800 SRM 734

10.

11.

12.

13.

14.

15.

16.

17.

18.

GROMMET RESERVOIR CAP PIN VACUUM FITTING VACUUM LINES CLAMPS BRAKE BOOSTER FILTER VACUUM LINE FITTING

Figure 9. Brake Booster and Master Cylinder

INSTALL 1. Put the master cylinder in position on the brake booster and install the nuts for the master cylinder. Install the brake booster on the mount. Install the nuts for the brake booster. Connect the push rod to the brake pedal. See Figure 8.

10

2. Connect the brake line at the master cylinder.

Connect the wires at the reservoir. Fill the reservoir and remove the air from the brake system as described in Brake System Air Removal in this section.

3. Adjust the brake linkage as described in Brake Pedal Adjustment.

1800 SRM 734

Brake System Air Removal

BRAKE BOOSTER FILTER, REPLACE 1. Remove the two clamps holding the old filter to the brake vacuum lines. Remove the brake booster filter. See Figure 9.

2. Install new filter onto brake vacuum lines. Install the two clamps to hold brake booster filter onto brake vacuum lines.

Parking Brake Repair REMOVE AND DISASSEMBLE

ASSEMBLE AND INSTALL

If the lever assembly for the parking brake must be removed from the cowl, use the following procedure (see Figure 10):

On the H3.50-4.00XMS (H70-90XM) units, the parking brake cables must be installed in the backplate before the service brake is installed. A snap ring holds the sheath of the parking brake cable in the backplate of the service brake. Install the parking brake cable in the backplate and install the snap ring that holds the sheath of the parking brake cable in the backplate.

1. Use blocks next to the tires to make sure the lift truck cannot move. Release the parking brake lever.

2. Remove the four nuts, bolts, and washers that fasten the bracket for the parking brake to the cowl. Disconnect the wires at the switches. Remove the bracket and brake lever assembly.

3. Loosen the jam nuts that fasten the threaded ends of the brake cables to the brake lever assembly.

4. Turn the adjuster knob counterclockwise until the brake cables are loosened. Disconnect the cables from the link.

5. The service brake assembly must be removed before the parking brake cable can be removed from the backplate of the service brake. A snap ring holds the sheath of the parking brake cable in the backplate of the service brake. Remove the snap ring and remove the parking brake cable from the backplate.

If the lever assembly for the parking brake was removed from the cowl, use the following procedure for installation (see Figure 10): 1. Make sure the parking brake lever is in the released position. Turn the adjustment knob until the link is adjusted to the bottom of the adjustment slot.

2. Adjust the jam nuts on the ends of the cable assemblies so that the threads of the cable sheaths extend 6 mm (0.25 in.) above their support plate in the lever assembly.

3. Install the round ends of the parking brake cables in their slots in the link. Tighten the upper jam nuts to hold the sheaths of the parking brake cables in their support.

4. Use the four capscrews, washers, and nuts and fasten the bracket to the inside of the cowl.

Brake System Air Removal The air must be removed from the brake fluid. Fill the reservoir for the master cylinder with brake fluid.

Always remove the air from the master cylinder first, then the wheel cylinders. Put one end of a rubber hose on the special fitting at the master cylinder or the wheel cylinders. Put the other end of the hose in a

container with brake fluid. Loosen the special fitting.

Push slowly on the brake pedal. Close the special fitting. Repeat the procedure until no air bubbles are seen in the container. Check the fluid level in the reservoir. Keep the reservoir full of brake fluid during these procedures.

11

Parking Brake Adjustment

1800 SRM 734

Brake Pedal Adjustment NOTE: The adjustment for the brake/inching pedal is in the section Single-Speed Powershift Transmission, Troubleshooting and Repair 1300 SRM 752 or Two-Speed Powershift Transmission, Troubleshooting and Repairs 1300 SRM 728.

Parking Brake Adjustment Make sure that the service brakes are adjusted and the operation of the automatic adjuster mechanism is correct before the parking brake is adjusted.

1. Turn the adjustment knob to raise the link and tighten the parking brake cables. Turn the adjustment knob until the parking brakes are fully applied when the lever is used to apply the parking brake. See Figure 10.

2. Test the operation of the parking brake. The lift truck with a capacity load must not move when the parking brake is applied on a 15% grade [a slope that increases 1.5 m in 10 m (1.5 ft in 10 ft)].

3. Check the operation of the switches on the parking brake.

1. SWITCH 2. PARKING BRAKE LEVER 3. ADJUSTMENT KNOB 4. ADJUSTMENT SLOT

5. EQUALIZER LINK 6. PARKING BRAKE CABLES 7. NUTS 8. COWL

Figure 10. Parking Brake Lever Adjustment

12

Parking Brake Switch Test (MONOTROLÂŽ Pedal Only)

1800 SRM 734

Parking Brake Not Applied Switch Test The Parking Brake Not Applied switch is located in the operator seat. This switch actuates an audible buzzer on the instrument cluster. When the operator leaves the seat for more than two seconds without applying the parking brake, the buzzer will be on continuously for 10 seconds. The buzzer operates whether the key switch is ON or OFF.

Parking Brake Switch Test (MONOTROLÂŽ Pedal Only) When the parking brake assembly and cables have been adjusted, the parking brake switches must be tested for correct operation.

WARNING If the brake switches are not adjusted correctly, the engine can be started with the parking brake released. The purpose of the left-hand switch (MONOTROL only) is to prevent the starter motor from being energized when the parking brake is not applied. The right-hand switch de-energizes the direction solenoids to put the transmission in Neutral (MONOTROL only) when the parking brake is applied.

1. Put the lift truck on blocks so that the drive wheels do not touch the ground or any other object. Put blocks at both sides of the steering tires to prevent movement of the lift truck.

2. Release the parking brake. The right-hand, twocircuit microswitch closes the electric circuit for the MONOTROL pedal (energizes the solenoids for the powershift transmission). The left-hand switch de-energizes the starting circuit.

the starter will not energize. Turn the ignition switch to the OFF position.

4. Apply the parking brake with the parking brake lever. The right-hand, two-circuit microswitch opens the MONOTROL circuit (de-energize the solenoids for the transmission). The starting circuit is energized by the ignition switch through the left-hand switch.

5. Turn the ignition switch to the START position.

The starter operates when the parking brake switch operates correctly. Turn the ignition switch to the OFF position.

6. Check the wires for the parking brake switches if the conditions from the results of Step 2 through Step 5 are not correct.

7. Apply the parking brake and start the engine.

Push the parking brake lever toward the released position, but do not push the release button. The parking brake will stay in the ON position and locked. The transmission must be in NEUTRAL any time the parking brake lever is applied. If the results of the test are not correct, check for wear and damage. Make repairs as necessary and repeat Step 1 through Step 7.

3. Turn the ignition switch to the START position.

If the parking brake switch operates correctly,

13