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In the interest of safety and to ensure compliance with the OSHA Regulations, the control of hazardous energy (lockout/tagout), the company has developed guidelines for proper energy control when performing service and maintenance. Before performing any service or maintenance machines, review the appropriate sections in this service manual for additional procedures to be followed.

In addition, the company recommends that all mechanics wear appropriate protective items, such as safety glasses, work gloves, and steel toed shoes, whenever performing service or maintenance work on company equipment.

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Battery

Gases produced by a battery can be explosive. Do not smoke, use an open flame, or create an arc or sparks in the vicinity of the battery. Ventilate an enclosed area well when charging.

Batteries contain sulfuric acid, which may cause severe burns. Avoid contact with eyes, skin, or clothing. In case of contact, flush immediately and thoroughly with clean water. Obtain medical attention when eyes are affected. A baking soda solution (one pound to one gallon of water) applied to acid until bubbling stops neutralizes the acid for safe handling and disposal.

Leakage voltage from battery terminals to the battery case can cause misleading trouble symptoms with the truck electrical system. Since components of the truck electrical system are insulated from truck frame, leakage voltage will not normally affect truck operation unless a short circuit or breakdown of circuit wire insulation to truck frame occurs.

A voltage check from battery connector terminal to the battery case should indicate near 0 volts. Typically, however, the sum of the voltages at both terminals will equal battery volts. This leakage voltage will discharge the battery. As battery cleanliness deteriorates, the usable charge of the battery decreases due to this self discharge.

Although a leakage voltage reading of 0 volts may not be possible, a cleaner battery will have more usable charge for truck operation and not affect operation of electronic devices on the unit.

Safety Rules

  • Wear protective clothing, such as rubber apron, gloves, boots and full-face shield, when performing any maintenance on batteries. Do not allow electrolyte to come in contact with eyes, skin, clothing, or the floor. If electrolyte comes in contact with eyes, flush immediately and thoroughly with clean water. Obtain medical attention immediately. Should electrolyte be spilled on skin, rinse promptly with clean water and wash with soap. A baking soda solution (one pound to one gallon of water) will neutralize acid spilled on clothing, the floor, or any other surface. Apply solution until bubbling stops, and rinse with clean water.
  • Keep vent plugs firmly in place at all times except when adding water or taking hydrometer readings.
  • Do not bring any type of flame, spark, etc., near the battery. Gas formed while the battery is charging is highly explosive. This gas remains in the cells long after charging has stopped.
  • Do not lay metallic or conductive objects on the battery. Arcing will result.
  • Do not allow dirt, cleaning solution, or other foreign material to enter cells. Impurities in electrolyte has a neutralizing effect reducing available charge.
  • If battery repair is planned, follow the battery manufacturer's instructions concerning repair practices and procedures.

Checking

Battery electrolyte level should be checked before each charge of the battery. The level should be maintained at 13mm (0.5 in.) above plates or just below the lower lip of the filler hole at all times. If low, add distilled water or approved local supply (consult battery manufacturer) at the end of a charge cycle. Do not overfill. For maximum battery life, specific gravity readings should be taken daily on a pilot cell and recorded. A different pilot cell should be selected on a monthly basis with readings taken on all cells at semi annual or annual intervals. Do not take specific gravity readings immediately after adding water. Water and electrolyte must be thoroughly mixed by charging before a reliable reading can be taken. Normal full charged specific gravity should be between 1.265 and 1.285.

  • Before disconnecting or connecting batteries to a charger, make sure the charger is "OFF". If an attempt is made to allow this while the charger is "ON", serious injury to you, the battery, and charger could result.
  • Before charging, make sure the battery cells contain the correct amount of water. Charging batteries with low water level might result in damage to the cells. When checking water levels, never use a match or lighter. Battery fumes are explosive.
  • Before connecting the battery cable to the truck receptacle, make sure the key switch is off and a controls are in the off position and the brakes are applied. The ✓ battery cable must be fully connected before the truck is used. If the plug is not making good contact, heat will weld the two parts of the battery connector together, making it difficult to remove and necessary to replace.
  • Battery terminals should be checked and cleaned of corrosion regularly. Good battery terminal contact is essential to charging often, if only for operation, but also for prop battery.
  • Battery cover should be closed except when charging.
  • The charging requirements will vary depending on the use of the equalizing truck. The battery should be given normal charge on a weekly basis. This characteristically should be an additional three hours at the finish rate.

Charging

CAUTION

Never smoke or bring flame near the battery. Gas fanned during charging is highly explosive and can cause serious injury.

Charging requirements will vary depending on use of truck. A battery with a specific gravity of 1.160 should be recharged. In some applications, more than one battery is required to provide ample power to the unit during the service period.

CAUTION

Never bring flame near the battery. Gas formed during charging is highly explosive and can cause serious injury.

Consult the charger manufacturer's manual covering your charger for hints on operation and maintenance.

Placing Battery on Charge

  • Park the truck at the charging station with the forks lowered and the key removed.
  • Make certain the charger control is in the off position.
  • Connect the battery to the charger, and make certain connectors are mated completely.
  • Set the timer for a specified time. Set for Normal; Daily Charge, except one night a week when the Equalize [Weekend] Charge should be used.
  • Check charger ammeter to make certain it shows charge.

Removing Battery from Charge

  • Make certain the charger is turned off.
  • Unplug the connector, using both hands, with a straight pulling motion.
  • Hang up the charger cable to prevent damage to the cable. (Broken connectors can cause poor connections and connector failures).
  • Make daily battery checks; add water as needed.
  • Connect battery to truck. Make certain connectors are mated completely.

Battery Stop Adjustment

To minimize the side-to-side (lateral) movement of the battery in the truck, the battery covers are equipped with adjustable stops. First, the battery must be centered in the power unit. Then, the adjustment screw on each battery retainer should be adjusted until it just contacts the battery surface. Snug the locking screw down on the adjustment screw and tighten jam nut. Do not over tighten the locking screw. Once the battery stops are adjusted, the battery covers should be removable without loosening the battery stop adjustments. Any time a battery of different size is installed, this adjustment is necessary. Refer to illustration below.

BATTERY WEIGHT

BATTERY RATING

MINIMUM

MAXIMUM

BATTERY TYPE

VOLTAGE

HOUR RATE

CAPACITY

690 kg (1520 lbs.)

860 kg (1900 lbs.)

24

6

1085

Battery Removal

CAUTION

When removing the battery, move the truck to an area intended for battery care. The floor must be level. Turn the keyswitch or toggle switch to the "off" position and remove the key. Disconnect the battery and lockout/tagout truck. Never move the battery partially from the truck without the roller stand in place. Lower load engaging means completely. If the battery is removed with load engaging means raised, use the hoist attached to the mast to provide tip over protection. Don't allow any metallic object to come in contact with the top of the battery cells. This may cause a short circuit when removing, transporting the battery. Use an insulator (such as plywood) to cover the top of the battery before and during removal.


Lockout-Tagout

Always turn key switch to "off', remove key and apply tag to steering wheel or twist grip with cable tie warning others truck is being serviced.

When maintenance is to be performed and the battery will be left in the truck, disconnect the battery, remove the main power fuses, and install a commercially available lockout device on the battery connector.

When maintenance is performed and the battery is removed from the truck, remove the main power fuses, install a lockout device on the trucks battery connector if possible, or, if possible, install a tag with a cable tie on the truck's battery connector so it cannot be removed easily.

1. Turn key switch off.

2. Open top cover and disconnect battery.

3. Remove battery cover (one side only)

4. Position battery roller stand next to truck. Align stand with battery. Battery roller stand should be the same height as the truck's compartment rollers and as long or longer than battery.

5. Roll battery onto stand. Using approved spreader bar, lift and move battery to charging area.

Battery Installation

CAUTION

Do not allow any metallic object to come in contact with the top of the battery cells. This may cause a short circuit when removing, installing, or transporting the battery. Use an insulator (such as plywood) to cover the top of the battery before and during removal and installation.

Make certain some battery or battery of equal weight is loaded into the truck for truck stability. See the data plate for minimum battery weight and type.

1. Check to be sure key switch is turned off.

2. Using approved spreader bar, move battery onto roller stand and push battery into battery compartment.

3. Remove roller stand and install battery cover. Make sure battery retainers are properly adjusted for the battery installed.

CAUTION

Spreader Bar retainers are not properly installed.

Be sure both retainers are in place and secure.

4. Connect battery and close top cover.

5. Turn key switch on and check truck operation.

Battery Care

CAUTION

Only qualified and experienced personnel should perform maintenance and repair on batteries.

  • Make certain the charger being used matches the voltage and amperage of the truck battery. This voltage is listed on the truck serial plate.
  • Before disconnecting or connecting batteries to a charger, make sure the charger is "OFF". If an attempt is made to do this while the charger is "ON", serious injury to you, the battery, and the charger could result.
  • Never use a match or lighter. Battery fumes are explosive.
  • Make certain the battery used meets weight, size, and voltage requirements of the truck (refer to the serial plate). NEVER operate the truck with an undersized battery.

Battery Cleaning

Always keep vent plugs tightly in place when cleaning the battery. When properly watered and charged, the battery will remain clean and dry. All that is necessary is to brush or blow off any dust or dirt that may accumulate on them. However, if electrolyte is spilled or overflows from a cell, it should be neutralized with a solution of baking soda and water (.37 kg [1 lb.] soda to 3.79 L [1 gal.] of water). To do this, remove the battery from the truck and clean with the solution of soda and water, brushing the soda solution beneath the connectors and removing grime from the covers. Then, rinse the battery with cool water from a low-pressure supply to remove the soda and loosened dirt. If batteries stay wet consistently, they may be either overcharged or overfilled. This condition should be investigated and corrected.

Troubleshooting

Records of battery specific gravity readings (charger-used, truck-used, etc.) can be the most effective troubleshooting aid. Contact your dealer for charts designed specifically for this purpose.

Voltage readings of each cell taken at the normal charger finish rate also indicate battery condition. New batteries will have cell voltages ranging from 2.055 volts to 2.065 volts. Older batteries may, however, range from 2.045 volts to 2.055 volts. These readings still indicate a battery in good condition.

A variation of .20 volts may be normal if certain cells are exposed to higher temperatures during discharge. Voltage differences that cannot be attributed to battery age or operating conditions indicate a weak cell(s), and maintenance is required.

CAUTION

Only qualified and experienced personnel should perform maintenance and repair on batteries.

TRACTION 020994

TRACTION With SENSORS 021008-001, 021008-002(EE), 020600-002(w/o Sensors)

Brushes:

No. of Brush Holders

1

1

No. of Brush Assemblies

4

8

No. of Brush Springs

4

8

Brush Length-New

33mm (1.3 in.)

33mm (1.3 in.)

Spring Tension on New Brushes

1360gm (48 oz.)

1360gm (48 oz.)

Min. Brush Length-Replace

16mm (.62 in.)

16mm (.62 in.)

Spring Tension Before Replacement

907 gm (32 oz.)

907 gm (32 oz.)

Commutator:

Max. Diameter- New

74mm (2.92 in.)

85.3mm (3.36in)

Min. Diameter- Reslotting

72mm (2.85 in.)

82.3mm (3.24 in.)

Min. Diameter- Replace

70mm (2.75 in.)

81.0mm (3.19 in.)

Bearings:

Lubricant

Hi Temp (Chevron SRI-2 or equivalent) 25-30% Fill

Hi Temp (Chevron SRI-2 or equivalent) 25-30% Fill

Cond. of Performance:

(No Load)

Volts

12

12

Max. Amperes

12

RPM

650

Field Resistance

(each at 75F [24C])

Series Ohms

.34

.37

Armature Resistance

(each at 75F [24C])

Ohms

.0055

.0038

Measured between bars

1 and 10

1 and 9

Frame Diameter:

170mm (6.70 in.)

190mm (7.5 in.)

Direction of Rotation

Reversible

Reversible

Brake System

The brakes can be released through the use of the drive/tow switch (DTS1) during a maintenance situation. When using this method to release the brakes, the truck will not have brakes available for stopping. The truck will not have traction control, and the power steering system will not work.

WARNING

Extreme care must be taken when using the drive/tow switch to release the brakes. The truck will be free-wheeling, and the brake pedal in the operator compartment will have no effect on braking. Brakes will only be applied when DTS1 is moved from the "tow" to the "drive" position.

  1. Lockout/tagout truck as described in Battery - Lockout/Tagout
  2. Chock wheels, or make sure truck is secured by some means, to keep it from rolling away
  3. When towing truck, make sure all operators are informed of truck's lack of braking
  4. Move switch DTS1 from "drive" position to "tow" position
  5. Insert brake harness, PC407, into distribution panel
  6. Move truck to an area intended for maintenance
  7. Move DTS1 from "tow" to "drive" position and disconnect battery
  8. Disconnect brake harness from distribution panel and connect to original connection, CA407

Capacitance

Due to capacitance voltage present in the Access 3 module, whenever performing maintenance that may permit contact with the bus bars and associated power cables, discharge the capacitors.

  1. Move truck to a secure, non-traffic maintenance area with level floor
  2. Lockout/tagout truck as described in Battery - Lockout/Tagout and disconnect battery
  3. Turn and hold keyswitch to the "start" position for 30 seconds; voltage lowered below 1 V
  4. Turn key switch to "off" and remove key
  5. Allow 5 minutes after battery disconnect for capacitors to discharge


Access 3

Hydraulic System

The hydraulic system in your truck is powered by gear-type pumps. These pumps, P1 & P2, supply oil flow for lift and accessory functions.

Maximum pressure is limited by an adjustable relief valve, RV1. The setting for RV1 is noted on the hydraulic schematics. Refer to the service manual index for pump, valve, and manifold information.

The illustration below shows hydraulic component location in the power unit.

  1. When maintenance is to be performed on the hydraulic system, to make sure the hydraulic system is not under pressure:
  2. Move truck to a secure non-traffic maintenance area with level floor
  3. No load on forks
  4. Completely lower load-engaging means (mast) or, if required for maintenance, block mast sections at appropriate height.
  5. Lockout/tagout truck as described in Battery - Lockout/Tagout.
  6. Open power unit doors and locate lift manifold
  7. Open manual lower valve to remove hydraulic pressure


Lift/Lower Manifold

Accumulator

The accumulator (hydraulic system shock absorber) contains a charge of inert gas such as dry nitrogen. Do not tamper with the gas valve on the accumulator in an attempt to reduce the amount of this charge. Use an accumulator charging equipment and procedures.

Hydraulic Circuits

This article section contains a brief description of the hydraulic circuits for SP trucks, which are typical of current standard units. Your unit may vary.

Lift Circuit - One-Speed Lift

When "lift" is selected, oil is drawn from the hydraulic reservoir to hydraulic pump P1. P1 supplies pressurized oil to the lift/lower manifold block. The oil enters the manifold block through port P1 and goes directly to check valve CV2. Oil passes through the manifold block until it exits port C1. Pressurized oil enters the lift cylinders and begins to extend the mast.

Relief Valve Operation

During the lift function, relief valve RV1 monitors hydraulic pressure. If oil pressure exceeds the relief pressure setting, the relief valve is forced open, allowing the pressurized oil to bypass the lift circuit. From the relief valve, oil exits from the manifold block through port T1. From port T1, oil passes through the return line filter and back to the reservoir.

Accumulation Operation

The accumulator is used as a shock absorber for the lift/lower hydraulic system. If the platform is stopped suddenly, the change in oil flow exerts pressure on the hydraulic system. The accumulator absorbs this oil pressure change by using the gas pressurized bladder located within the accumulator. The bladder acts as a pillow to the pressurized oil, cushioning the applied pressure within the hydraulic circuit. The typical symptom of a bad or de-pressurized accumulator is abrupt starting and stopping of the platform during lift or lower.

Low-Speed Lift

When the lift button is depressed to the first detent, oil is drawn from the hydraulic reservoir to hydraulic pump P1. The hydraulic pump supplies pressurized oil to the lift/lower manifold block. The oil enters the manifold block through the port P1 and goes directly to check valve CV1. The oil passes through the manifold block until it exits port C1. Pressurized oil enters the lift cylinders and begins to extend the mast.

High-Speed Lift

When the lift button is completely depressed, pump P2 turns on simultaneously with pump P1. The hydraulic pump P2 supplies pressurized oil to the lift/lower manifold block. The oil enters the manifold block through port P2 and goes directly to check valve CV3. This oil passes through the manifold block, where it joins the oil supplied from the pump P1 out to the lift cylinders.

Relief Valve Operation

During the lift function, relief valve RV1 monitors hydraulic pressure. Oil pressure exceeding the relief pressure setting will force RV1 open, allowing the pressurized oil to bypass the lift circuit. Oil exits the manifold block through port T1. From port T1, oil passes through the return line filter and back to the reservoir.

Accumulator Operation

The accumulator is used as a shock absorber for the lift/lower hydraulic system. If the platform is stopped suddenly, the change in oil flow exerts pressure on the hydraulic system. The accumulator absorbs this oil pressure change by using the gas pressurized bladder located within the accumulator. The bladder acts as a pillow to the pressurized oil, cushioning the applied pressure within the hydraulic circuit. The typical symptom of a bad or de-pressurized accumulator is abrupt starting and stopping of the platform during lift or lower.

Lower Circuit- One-Speed/Two-Speed Lower

When "lower" is selected, oil begins to exit the lift cylinder. Oil leaving the cylinder is monitored by the internal velocity fuse in each cylinder.

Velocity fuses are designed to prevent sudden release of hydraulic oil from the cylinder under a condition such as a line rupture. If a cylinder line ruptures, the oil exiting the cylinder would create pressure on the velocity fuse, forcing the fuse to close. This will block the oil from exiting the cylinder.

Lower

When the lower button is depressed, oil exits the lift cylinders and enters the lift/lower manifold block through port C1. The oil passes through the open envelope (envelope without a check valve) of the proportional solenoid valve (PVL), which is in the energized position. Oil is directed from the PVL to the pressure compensator valve (PCL). The PCL limits the maximum oil rate. Once the oil exits the PCL, it is directed out of the manifold through port T1. From port T1, the oil enters the return line filter and then goes back to the reservoir.

A partially opened proportional valve performs slow-speed lowering. High-speed lowering is accomplished by completely opening the proportional valve.

Manual Lowering Circuits

The manual lowering feature is used to lower the mast during truck-down situations. The manual lowering valve (MVL) is located on the lift/lower manifold block. When the MVL is actuated, oil trapped in the cylinder is released. Oil enters the lift/lower manifold through port C1. From port C1, the oil flow is directed to the manual lowering valve's open envelope (envelope without check valve). Oil exits the manifold through port T1. From port T1, the oil enters the return line filter then back to the reservoir.


Manual Lower - One Speed Lift/Lower


Manual Lower-Two Speed Lift/Lower

Reservoir

With all cylinders in the retracted position and after all air has been bled from the hydraulic system, fill the reservoir so that the oil level is at the high mark on the reservoir sight gauge (1). The total capacity of the hydraulic system at this level should be approximately 13 liters (3.5 gallons) for trucks with one-speed lift and 17 liters (4.5 gallons) for trucks with two-speed lift.

Hydraulic Lines and Fittings

  • Blow air through all hoses and lines to remove loose particles before installing. Any rubber hose with wire-braid inner construction, and any steel tube lines that have been collapsed or kinked, are permanently damaged and must be replaced, even if the damage is not externally visible.
  • Flexible hoses must be replaced if they collapse in normal operating position.
  • All connections are to be leak-free.
  • The beaded elbows in suction ports of all pumps must be positioned such that the suction hose retains its full volume flow and does not collapse.

WARNING

AVOID HIGH-PRESSURE FLUIDS- Escaping fluid under pressure can penetrate the skin, causing serious injury. Relieve pressure before disconnecting hydraulic lines. Tighten all connections before applying pressure. Keep your hands and body away from pinholes, which eject fluids under high pressure. Use a piece of cardboard or paper to search for leaks; do not use your hand.

Any fluid injected into the skin under high pressure should be considered as a serious medical emergency despite an initial normal appearance of the skin. There is a delayed onset of pain, and serious tissue damage may occur. Medical attention should be sought immediately by a specialist who has had experience with this type of injury.

Filter

The spin-on filter cartridge has been tightened by the manufacturer.

When replacing filter, apply a film of oil to the seal and hand-tighten until the seal snugly contacts the filter head.

NOTE:

Do not tighten the filter with the use of a wrench. A wrench should only be used for removal of the filter.

Use only a good grade of hydraulic oil such as Mobil DTE 24 or an oil equal to it. On trucks equipped to operate in below-freezing temperatures, Mobil Aero HFA, or something equal, is recommended in a 50/50 blend with standard hydraulic oil.

NOTE:

Do not use hydraulic brake fluid.

Drift Test

All drift tests should be conducted with a capacity load (refer to serial plate for the rated capacity of your truck). The material used for the test load must be evenly stacked within the limits of a four foot square pallet and must be secured to the fork carriage with the forks spread to their maximum width.

CAUTION

Never stand or work under a suspended load.

Lift Drift Test

Elevate the test load above staging height. After five minutes, measure the distance the forks have drifted. Drifting in excess of 15 mm (0.5 inches) over a five-minute period is considered unacceptable.

NOTE:

The lift measurements is to be taken from the tip of the fork to the floor.

Occasionally, a slight creep of the fork assembly may occur due to internal leakage in the piston pack, but it can also be caused by leakage in check or manifold valves. To seat these valves properly when this occurs, lift and lower the forks to flush out any foreign material from the valve seat. A thorough check for leaks in the system should be conducted if abnormal oil losses occur. The hydraulic system is designed to eliminate mechanical damage even if fittings become loose.

Freezer Preparation

Trucks may require a mixture of low-temperature hydraulic oil blended with standard hydraulic oil when used in a freezer or cooler. 100% low-temperature oil is too thin for most cold-storage operations and, therefore, could shorten the life of cylinder packings and pumps if used in higher ambient temperatures.

NOTE:

Trucks equipped with velocity fuses may experience staging issues if an insufficient mix of low-temperature oil has been used.

For truck applications operating continually in temperatures at or above 4C (40F), use 100% standard hydraulic oil.

For truck applications primarily operating in a cooler environment with intermittent freezer entry, use a 50/50 blend, 50% low temperature and 50% standard hydraulic oil.

For truck applications primarily operating in a freezer environment, use an 80/20 blend, 80% low temperature and 20% standard hydraulic oil.

The proper mixture of freezer hydraulic oil will ensure the best and most efficient operation of your truck equipment.

Pump Gear

Overhaul the pump only in a clean, dust-free location, using clean tools and equipment. Dirt or grit will damage the highly polished machined surfaces and will result in leakage or premature failure of the pump.

Before beginning the disassembly, scribe match marks on the body assembly, the end cover, and mounting flange to ensure that the pump will be reassembled properly. This pump can be assembled for either clockwise or counterclockwise rotation, as viewed from the end of the splined drive gear assembly. Arrows are molded into the body assembly, and the word "ROTATION" appears on the mounting flange to aid in determining the pump's rotation. Note which direction the arrow is pointing next to the word "ROTATION" prior to disassembly.

Oil Seal Removal

The oil seal (index 11) is best removed by applying pressure simultaneously to the pump inlet and outlet ports. This has the effect of pressurizing the seal cavity and forcing out the oil seal, while ensuring that the pressure on each side of the lobe seals (item 3 & 4) is equalized so that these seals are not displaced. If the oil seal is distorted and leaking badly, it may not be possible to build up sufficient pressure to remove it in this way. In this case, disassemble the pump as far as step 5 of the "DISASSEMBLY PROCEDURE", and clamp the mounting flange securely in a soft-jawed vise. The seal can then be removed with the use of a seal-removing tool. Be careful not to damage the mounting flange seal bore or the drive shaft's sealing surface.

Oil Seal Replacement

  1. Make sure the seal housing in the pump-mounting flange is clean and free from burrs.
  2. Pack the space between the lips of the seal with a high-melting-point, mineral-based grease.
  3. Seat the oil seal.

  • If the mounting flange has been removed, start the oil seal squarely into the housing, with the garter spring facing inward, and press home to the full depth of the recess.
  • If the pump is assembled:

Slide an "Assembly Sleeve" over the shaft splines until it comes in contact with the shaft shoulder. Lightly grease the sleeve. Slide the oil seal, with the garter spring facing inwards, over the sleeve, and start it squarely into the housing.

4. Press the seal into the full depth of the recess.

5. Remove the assembly sleeve.

Lifting and Blocking

Puck stability decreases dramatically if the load wheels are raised more than 13 mm (0.5 inch). Attach sling and overhead device to all cross members of the mast to prevent THE truck from tipping over when raising the side of the truck.

NOTES:

  • Hydraulic Jack - Capacity 3620 kg. (8000 lbs.)
  • Crown part number: 122599
  • Collapsed height minimum: 60 mm (2.25 in.)
  • Raised height maximum: 400 mm (16 in.)
  • Jack Stand - capacity 4500 kg. (10,000 lbs.) Commercially available.


WARNING: Do not raise the load wheels more than 13mm (0.5 in.) from the floor to position the hardwood block.

Gear Assembly

Whenever assembling the steering feedback gears, it is important that all gear backlash be removed. If this is not done, steering accuracy and response is reduced. Refer to figure below.

Place the nyliner bearing onto the gear shaft. Next, place one end of the torsion spring into the small hole on the gear, as shown. Slide the 18T gear onto the gear shaft, aligning the other end of the torsion spring with the small hole on that gear. Slide the second nyliner bearing onto the gear shaft. Install the third nyliner bearing on top, as shown.

Turn the top gear until the larger hole on both gears is aligned, approximately 2 teeth. Slide a 3.1mm (1/8 in)drill bit into the holes from the bottom to keep the gears aligned.

Slide the gear shaft up through the power unit. Once the gears are meshed with the steering gearbox and drive unit gears, install the flatwasher(s)(AR) and the retaining ring to keep the gear assembly from sliding out.

Slide the flatwasher onto the encoder shaft, and insert into the gear-shaft assembly. Make sure the extension spring is installed. If necessary, rotate the gear shaft so the set screw faces straight back to allow for easy access for tightening. Tighten the set screw to secure encoder shaft to the gear shaft.

Make certain the set screw is tightened on the flat part of the encoder shaft. Remove the drill bit from gear assembly.

  1. The steer wheel feedback encoder must be set to "index" when the steered wheel is in the straight ahead position. To set and check the steering feedback encoder:
  2. Connect the service terminal to the connector on the platform below the control module, enter the "SHOW"menu of terminal operation, and select the "VIEW ENCODER COUNTS" menu. If the truck has not been given a steering command since power-up, steering timeout will be 1 second. If a steering command has been given since power-up, steering timeout is 2 minutes. To obtain the 1-second timeout for improved steering alignment efforts, turn tiller slightly. Timeout will change to 1 second.
  3. After timeout, form a straight line with the alignment mark on the steered wheel drive unit and the alignment mark on the drive unit mounting bracket. The steered wheel is now in the straight-ahead position.
  4. Observe the wheel counts on the service terminal display. Since the steered wheel is in the straight-ahead position, the display should show an "I" and a number. If only a number is present, open the power unit doors and locate the steering feedback module. Remove the steering feedback cover. Loosen the two screws holding the encoder in place. Turn the encoder very slowly until the "I" and number appear on the service terminal display. While maintaining encoder position to keep this display on the service terminal, secure the adjustment with the two screws. Make certain the cleats holding the encoder have their flat surfaces turned away from the encoder.
  5. Exit the "SHOW" menu, and disconnect the service terminal.
  6. Install the cover, close the power unit doors, and return to operation.

CAUTION

The steering indicators will not represent the proper steer angle. The steering feedback encoder must be set to ensure the steered wheel is set to straight-ahead position.

Blocking Masts

Set 100mm (4 inches) by 100mm (4 inches) or bigger hardwood blocks of the appropriate length for supporting mast channels. Block both mast rails of each stage to maintain truck stability.

Revove any carriage-mounted accessory (e.g., roll loader, etc.) before blocking masts. These accessories add significant weight to the mast.

  1. Move truck to a secure non-traffic maintenance area with level floor
  2. Chock wheels of truck and refer to "Lifting and Blocking" of this article
  3. Connect battery
  4. Raise forks and position blocks under first stage mast of appropriate length; do not block first stage mast when work at main frame base is to be performed; set blocks under the platform only
  5. Using clamps, secure blocks to mast channels
  6. Using manual lowering valve, lower platform and position appropriate-length blocks under platform frame in mast channels
  7. Using clamps, secure blocks to mast channel or first-stage block
  8. Continue to lower platform until platform frame rests on blocks
  9. Lockout/tagout truck as described in Battery-Lockout/Tagout