Equipment experts throughout the industry know that performing proper preventive maintenance on schedule helps any kind of machinery deliver peak performance and contributes to long equipment life.
No matter whether you're operating agricultural machinery, construction equipment, or industrial tools, preventive maintenance is vital to productivity and profitability.
Because the skid-steer loader is one of the most widely used pieces of equipment in construction work, Western Builder asked Tom Yost, agricultural equipment power technical instructor at Fox Valley Technical College in Appleton, WI, about maintenance tips that can help protect the performance and extend the life of a skid-steer loader.
Now in his fourth year of teaching power technology at Fox Valley Tech, Yost has 20 years of experience servicing powered equipment.
During his more than 20 years of experience, Yost has been a service technician both in a shop and on the road, has been the service manager for an equipment dealership, and is now a technical-college instructor .
Says Yost, “Having and following an equipment-maintenance plan definitely saves on the repair bill. Changing oil, changing coolant, lubricating, and making adjustments as the manufacturer specifies definitely increases a piece of equipment's performance, service life, and resale value. Well-maintained equipment holds its value better than poorly maintained equipment.”
Here are Yost's tips for maintaining any skid-steer loader:
• Make sure that all the safety equipment works. The seat belt and seat-belt switch should work correctly. Be sure the lap-bar switch operates, and that none of the safety switches are bypassed.
• Safety decals are in place and not damaged or missing.
• Make sure the interlock safety system is working, so the boom or bucket doesn't operate when the operator is not in the seat or the seat belt or lap bar are not being used.
• Check the operation of the parking brake. Don't just check on level ground. Drive on a grade and check. Manual parking brakes can be adjusted to a point before replacing. Electrically activated ones may have component problems (solenoids, switches, etc.) or worn internal parts.
• Check the ROPS for loose hardware. This needs to be secure and not damaged.
• Clean out the cab and foot pedal area. Too many times with foot controls, mud builds up under the foot pedals and they cannot be moved.
•Make sure there are safety treads on the steps.
• Check the batteries. Remove battery connectors. Check the level of the electrolyte. If low, add distilled water - not tap water. Perform a specific-gravity test on the battery. Readings should be between 1.225-1.280. If below, the battery should be charged and rechecked. Then load test the battery. Battery posts need to be cleaned. Any battery acid should be washed off using baking soda andwater mix.
• Check the battery cables. Any evidence of battery acid on the connectors indicates corrosion is happening. Be aware that even if you clean the acid off, there may be corrosion inside the cable ends, which can cause a bad connection. If in doubt, replace the cable.
• Check the operation of the lights, back-up alarms, and monitoring gauges.
• Check the condition of the charging system. Start with the belt tension, condition of the belt and the pulleys. If a new belt sits down into the sheaves of the pulley, the pulley is probably worn and the life of the belt will be shortened. Using a voltage meter, check the alternator output. It should be over 13 volts and not more than 14.5-15 volts. If available, use a carbon pile and amperage gauge and check maximum alternator output. Sometimes the charging system may be working, but not 100 percent.
• Inspect wiring harnesses for wear from rubbing against the frame or being pinched. More and more of our electrical circuits are being controlled by controllers. Some of the systems use low voltage and any little resistance will create problems. Check electrical connections. If necessary, clean up with an electrical contact cleaner and use dielectric grease.
• Check the starting system. Does the motor turn over every time starter is operated? Is there any grinding noise when the starter operates? Is the starter or the solenoid getting hot when operating? Does the motor turn over very slowly? All are indications that there might be something wrong with the starter or connections to the starter.
• Check for oil leaks around the front engine seals, rear engine seals, pan gaskets, etc. Test the cooling system.Pressure-test to find leaks. Coolant should be tested and conditioner should be added accordingly. Change the coolant according to the operator's manual. Not maintaining the condition of the coolant can lead to having coolant in the engine oil. Coolant can react to the cylinder liners and O-rings and eat away them.
•Inspect the water pump bearings and seal.
•Inspect drive belts for wear and cracks.
• Check the turbocharger, if the machine is equipped with one. Pull the intake hose off and check for radial and linear movement of the compressor wheel. If the wheel is rubbing on the housing, it needs to be replaced.
• Perform general maintenance.
• Check the engine motor mounts for wear or tightness.
• Have an oil analysis done. This will indicate what the internal components of the engine are like. An analysis costs about $10-$30. The first time will give you a base to work with, and the next time you do this, the analysis can show what problems might be starting. The early alert can save money by alerting you to make repairs before a major failurehappens.
• The engine valves should be adjusted every 1800-2000 hours.
• Pull injectors and have them tested and cleaned every 2000 hours sooner if you notice a difference in power starting or exhaust smoke.
• Use fuel conditioner to help keep your fuel system operating properly.
•Drain water from the fuel tank. Condensation happens.
• Check all connections of the air intake system. Dirt can get past the smallest of openings. It is bad if it is after theair filter.
•Make sure all guards are in place and in good repair.
• Check all boom pins and bushings for wear. Make sure they take grease.
•Check all hardware to be sure it is tight.
• Check for external oil leaks (hoses, connections andcylinders). Check for hoses rubbing against the frame.
• Check/clean pins for quick-attachments and buckets. They build up with rust and dirt.
• Check controls and linkages for wear and ease of operation. Foot-control pivot points tend to seize up.
• Check the boom for cracks, especially around the welds.
• Put the skid loader up on blocks and check the steering adjustments. Check wheel speed in both forward and reverse. With the throttle wide open, the difference between the left and right side should be+/- 1 mph. This is your tracking adjustment. Adjust stops accordingly. With the levers in neutral and the throttle wide open, the wheels should not creep. Adjust as needed.
• Check the steering linkage for wear. The ball and socket joints do wear out.
• Some levers may move by themselves. Check the centering adjustment and or dampener shock used to stabilize thelever in neutral.
• With the skid loader up on blocks, check the tension of the chain case drive train. This is done by holding one wheel and rotating the other back and forth. The distance that you are able to move it should be minimal. Check manual for specifications. Tighten chain to specification.
• Remove the wheels and clean the material buildup behind them.
• Check the axle bearing for end play and radial play. If play is excessive, remove and inspect the axle. Replace if needed.
• Drain the chain-case oil. You may see water in with the oil. Water can accumulate from condensation or a leak in the top of the chain case. Also check for metal filings in the oil. A small amount may be normal, but if the oil is very silver, there may be a problem in the chain case (sprocket wear, bearing failure, bushing failure, chain wear or some metal on metal). Some chain-case drives incorporate the mechanical parking brake. Filings may be coming from the brake disk.
• If you have the gauges and equipment, it would be a good time to check the hydrostatic high-pressure and case-drain flow or pressures. Low hydrostatic pressures or high case-drain flow or pressure could indicate a weak hydrostatic system. You will need some technical information to do this.
• Change the hydraulic filter, cut it open, and inspect for contamination. You should not find excessive amounts. Too much indicates that there may be a hydraulic component failure.
• Tire size and pressure should be the same. Any differences cause a lot of stress on the drive system. One wheel works against the other.
• On track loaders, inspect the track and also the drive sprockets. The sprocket teeth should not be hooked and the track should not fit loosely between the sprockets.
• Loosen the track and inspect the bearings of the idler and bogie wheels.
• Inspect the hoses between the hydrostatic pump and drive motor. These are high-pressure hoses and any external wear of the hoses can lead to a major oil leak and safety concerns.
• Inspect the hydrostatic pump and drive motor area for oil leaks. This is a common place for leaky hoses, fittings, seals or O-rings. A small oil leak can turn into amajor one.
Editor's Note: To find out more about Fox Valley Technical College's power technology courses and classes, visit www.fvtc.edu or call 1-800-735-3882.