Caterpillar 426 - Daily Maintenance

Backhoe Boom, Stick, Bucket, and Cylinder Bearings - Lubricate

• Apply lubricant to the grease fitting (1) for the head end of the boom cylinder. Apply lubricant to the grease fitting (2) for the rod end of the boom cylinder

• Apply lubricant to the grease fitting (3) for the boom pivot. There is one grease fitting on each side of the machine.

Backhoe Boom, Stick, Bucket, and Cylinder Bearings - Lubricate 2

• Apply lubricant to the grease fitting (4) for the head end of the stick cylinder. Apply lubricant to the grease fitting (5) for the rod end of the stick cylinder.

• Apply lubricant to the grease fitting (6) for the pivot pin for the stick.

• Apply lubricant to the grease fitting (7) for the head end of the bucket cylinder. Apply lubricant to the grease fitting (8) for the rod end of the bucket cylinder.

• Apply lubricant to the grease fitting (9) for the top of the link.

• Apply lubricant to the grease fitting (10) for the bottom of the link.

• Apply lubricant to the grease fitting (11) for the pivot pin.

• Apply lubricant to the grease fitting (12) for the bucket pivot pin.

Backup Alarm - Test

• Turn the engine start switch key to ON in order to perform the test.

• Apply the service brake. Move the transmission direction control lever to REVERSE position.

• The backup alarm should immediately sound.

• The backup alarm will continue to sound until the transmission direction control lever is moved to the NEUTRAL position or to the FORWARD position.

Brake Reservoir Oil Level - Check

• Pull the hood release lever (1) in order to open the engine access door (2) on the top of the machine.

Service Brake Holding Ability Test

• Start the engine. Raise the bucket slightly.

• Apply the service brake. Release the parking brake.

• Move the transmission control lever to THIRD SPEED FORWARD.

• Gradually increase the engine speed to high idle. The machine should not move.

• Reduce the engine speed to low idle. Move the transmission to NEUTRAL. Engage the parking brake. Lower the bucket to the ground. Stop the engine.

Secondary Brake Holding Ability Test

• Start the engine. Raise the bucket slightly.

• Engage the parking brake.

• Move the transmission control lever to THIRD SPEED FORWARD.

• The parking brake indicator light should come on and the parking brake alarm should sound

• Gradually increase the engine speed to high idle. The machine should not move.

• Reduce the engine speed. Move the transmission to NEUTRAL. Lower the bucket to the ground. Stop the engine.

Cooling System Level - Check

• The radiator cap is located on the top of the radiator on the left side of the machine. Remove the radiator cap slowly in order to relieve system pressure.

• Maintain the coolant level within 13 mm (0.5 inch) of the bottom of the filler tube. If you need to add coolant daily, check the cooling system for leaks.

• Inspect the radiator cap seal. Replace the radiator cap seal if the radiator cap seal is damaged.

• Install the radiator cap. Close the access panel.

Engine Air Filter Service Indicator - Inspect

• Service the air cleaner only with the engine stopped. Engine damage could result.

• The filter service indicator is located under the engine access door on the top of the machine.

• Start the engine. Run the engine at high idle. If the yellow piston in the filter service indicator enters the red zone, service the air cleaner. Stop the engine.

Engine Oil Level - Check

• Pull the hood release lever (1) in order to open the engine access door (2) on the top of the machine.

• While the engine is stopped, maintain the oil level between the “ADD” mark and the “FULL” mark on the engine oil dipstick (3).

• If necessary, remove the oil filler cap (4) and add oil.

• Clean the oil filler cap and install the oil filler cap.

• Close the engine access door.

Extendable Stick Pads - Inspect/Replace (If Equipped)

• Check the extendable stick for slop. Shim the extendable stick pads in order to maintain an acceptable fit and reduce slop.

• Do not apply an excessive amount of a silicone based lubricant. Dirt can be attracted to the lubricant and dirt can cause abrasion to the pad assemblies and wear to the pad assemblies.

• The extendable stick pads do not normally require any lubrication. If the extendable stick becomes noisy, a small amount of a silicone based lubricant may be applied.

Fuel System Water Separator - Drain

• Loosen the drain valve on the bottom of the fuel filter. Allow the water and the sediment to drain into a suitable container.

• Tighten the drain valve.

• If the engine fails to start, change the fuel filter. If there is a power loss, change the fuel filter.

Hydraulic System Oil Level - Check

• The sight gauge for the hydraulic tank is located on the left side of the machine. Move the backhoe to the transport position and lower the loader bucket to the ground.

• Turn off the engine. Wait about five minutes before you check the hydraulic system oil level.

• Maintain the oil level in the sight gauge between the “MIN” mark and the “MAX” mark.

Kingpin Bearings (Front) - Lubricate

• Apply lubricant to the grease fitting on the top of each kingpin.

Single Tilt Machines

• Apply lubricant to the grease fittings (1) for the frame and for the lift arm. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fitting (2) for the pivot for the linkage of bucket positioner and lift kickout.

• Apply lubricant to the grease fittings (3) for the head end of the lift cylinder. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (4) for the rod end of the lift cylinder. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (5) for the pivot pin at the loader lift arm. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (6) for the pivot bearings for the bucket tilt cylinder. There is a grease fitting in each linkage (four total).

• Apply lubricant to the grease fitting (7) for the rod end of the tilt cylinder.

• Apply lubricant to the grease fittings (8) for the lower pivot pins. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (9) for the upper pivot pin. There is a grease fitting for each side of the machine.

Parallel Lift Machines

• Apply lubricant to the grease fittings (1) for the lower pivot pin of the quick coupler assembly. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (2) for the upper pivot pin of the quick coupler assembly. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (3) for the upper pivot pin of the tilt linkage. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (4) for the rod end of the tilt cylinder. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (5) for the rod end of the lift cylinder. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (6) for the center pivot pin of the parallel linkage. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (7) for the head end of the tilt cylinder. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (8) for the frame and for the lift arm. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (9) for the frame and for the parallel linkage. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (10) for the head end of the lift cylinder. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (11) for the lower pivot pin of the parallel linkage. There is a grease fitting for each side of the machine.

• Apply lubricant to the grease fittings (12) for the lower pivot pin of the tilt linkage. There is a grease fitting for each side of the machine.

Seat Belt - Inspect

• Always check the condition of the seat belt and the condition of the mounting hardware before you operate the machine. Replace any parts that are damaged or worn.

• Regardless of the appearance of the seat belt, the seat belt should be replaced at every three year interval. A date label is attached to each seat belt. Use this label in order to determine the age of the seat belt.

• Inspect the seat belt for webbing that is worn or frayed. Replace the seat belt if the seat belt is worn or frayed.

• Check the buckle for wear or for damage. If the buckle is worn or damaged, replace the seat belt and/or the buckle.

• Check the seat belt mounting hardware for wear or for damage. If the seat belt mounting hardware is worn or damaged, replace the seat belt mounting hardware. Make sure that the mounting bolts are tight.

Secondary Steering Test (If Equipped)

• If hydraulic pressure is lost during machine operation, the secondary steering system will become active.

• Note: With the machine at rest, the steering during this test cycle may require more effort than normal steering. Both hands may be required to steer.

• Before you start the engine, turn the steering wheel while the vehicle weight is on the front wheels. Turn the front wheels from the center position to each stop and return to the center position.

• Failure of the front wheels to complete the above cycle indicates a malfunction of the secondary steering system. The machine should not be driven until the problem is corrected.

Stabilizer and Cylinder Bearings - Lubricate

• Position the stabilizer, as shown.

• Apply lubricant to the grease fitting for the head end of the cylinder

• Repeat for the other stabilizer.

• There is a total of two grease fittings.

Swing Frame and Cylinder Bearings - Lubricate

• Apply lubricant to the grease fitting (1) for the top swing pin.

• Apply lubricant to the grease fitting (2) for the bottom swing pin.

• Apply lubricant to the grease fitting (3) for the eye of the swing cylinder. Repeat for the other swing cylinder.

• Apply lubricant to the grease fitting (4) for the bearing on the top of the swing cylinder. Repeat for the other swing cylinder.

• Apply lubricant to the grease fitting (5) for the bearing on the bottom of the swing cylinder. Repeat for the other swing cylinder.

Tire Inflation - Check

• Measure the tire pressure on each tire. Consult your Caterpillar dealer for the correct load rating and for the correct operating pressures.

• Inflate the tires, if necessary. Refer to Operation and Maintenance Manual, “Tire Inflation with Air” and Operation and Maintenance Manual, “Tire Inflation with Nitrogen”.

Transmission Oil Level - Check

• Pull the hood release lever (1) in order to open the engine access door (2) on the top of the machine.

• Remove the dipstick/fill plug for the transmission.

• Maintain the oil level within the crosshatched region on the “CHECK WITH OIL WARM” side of the dipstick/fill plug when the transmission is warm. Add transmission oil, if necessary

• The transmission can be checked with cold transmission oil. Check the oil level with the cold oil check side of the dipstick. The engine must be stopped in order to do a cold oil check.

• Clean the dipstick/fill plug and install the dipstick/fill plug

Walk-Around Inspection

• Inspect the backhoe bucket (14) for damage or for excessive wear. Inspect the backhoe linkage (1) for= damage or for excessive wear. Repair the bucket or the linkage, if necessary. Replace any bucket teeth, if necessary.

• Inspect the loader bucket (9) for damage or for excessive wear. Inspect the linkage (8) for damage or for excessive wear. Repair the bucket or the linkage, if necessary. Replace any bucket teeth, if necessary.

• Inspect the transmission (13) for leaks. Inspect the torque converter for leaks. Correct any leaks. Check the hoses around the transmission.

• Inspect the hydraulic system for leaks. Inspect the hydraulic tank (4), cylinder rod seals, hoses and tubes. Also inspect plugs, couplings and fittings. Correct any leaks.

• Inspect the engine compartment (6) for trash buildup. Remove any trash buildup that is in the engine compartment. Clean the screens on the engine access doors.

• Inspect the belts for the engine attachments (12) for worn belts, for cracked edges or for frayed edges. Replace any damaged belts.

• Inspect the cooling system for leaks, for faulty hoses, and for trash buildup. Correct any leaks and remove any trash buildup from the radiator (7).

• Inspect the tires (10) for damage and for proper inflation. Replace any missing valve caps. Tighten any loose bolts.

• Inspect the axles (11) for leaks. Inspect the front differential for leaks and the rear differential for leaks.

• Check the torque on new wheels or repaired wheels. Refer to Operation and Maintenance Manual, “Wheel Nut Torque - Check”.

• Inspect the engine air cleaner (5) for dirt buildup. Remove the dirt from the engine air cleaner.

• Service the air filter elements when the yellow piston enters the red zone on the filter service indicator.

• Inspect the steps and handholds (3). These objects must be clean. Also, these objects must be in good condition. Inspect the Rollover Protective Structure (ROPS) for damage.

• Notify your Caterpillar dealer for repairs, if necessary. Tighten any loose bolts on the ROPS.

• Make sure that the access covers and the guards are secured. Inspect the access covers for damage and the guards for damage.

• Inspect the lights (2) for broken bulbs and for broken lenses. Replace the bulbs or lenses, if necessary.

• Inspect the operator’s compartment for cleanliness. Keep the operator’s compartment clean.

• Adjust the rearview mirrors for best visibility.

Wheel Nut Torque - Check

• Check the torque on new wheels or repaired wheels after every ten service hours until the specified torque is maintained.

• Put a drop of oil on all wheel studs on reassembly

• Torque the nuts to 400 ± 40 N·m (295 ± 30 lb ft). Use a star pattern when you torque the nuts.

• Check the nuts on all four wheels.

Windows - Clean

• Use commercially available window cleaning solutions in order to clean the windows. Clean the outside of the windows from the ground unless handholds are available.