Agricultural Mechanics 8201-B Maintenance of Agricultural Tractors and Equipment PDF

# Agricultural Mechanics 8201-B - Maintenance of Agricultural Tractors and Equipment ## Introduction Maintenance is the regular care of something in order for it to perform well for long periods of time. Maintenance helps something to "maintain" as close to its original condition as possible. As hu...

# Agricultural Mechanics 8201-B - Maintenance of Agricultural Tractors and Equipment ## Introduction Maintenance is the regular care of something in order for it to perform well for long periods of time. Maintenance helps something to "maintain" as close to its original condition as possible. As humans, we cannot stop the aging process of our bodies. However, we attempt to maintain our health and slow the aging process by proper diet, rest, and exercise as prescribed by doctors. If we neglect our bodies, our health deteriorates and our performance decreases or stops. As related to agricultural tractors and equipment, preventive maintenance is the performance of regularly scheduled service and adjustments recommended by manufacturers. This is done to prevent excessive wear so the equipment doesn't break or wear out so quickly, and to assure safe and efficient operation. Preventive maintenance is not repairing the equipment after it breaks. Agricultural engineers employed by these manufacturers have "prescribed" recommended procedures to maintain the "health and well being" of agricultural vehicles and equipment. Simply, the purposes of preventive maintenance are to: 1. Promote safe equipment operation. 2. Reduce down-time by preventing major part failure. 3. Reduce operating and repair costs. An ounce of Preventive Maintenance may prevent several pounds of junk parts. **Diagram:** | | | | --- | --- | | Observation/Time | Reduced Down Time | Reduced Operating Cost/Safety | | Grease/Oil/Filters | 100# of junk parts | | An ounce of preventive maintenance | It is difficult to put a dollar value on the benefits of safety. Doctor and hospital bills are expensive, but money cannot remove all the pain and suffering, replace arms or legs, or bring back lives often caused by equipment failure. Safety should be first and foremost in every preventive maintenance program. It is true that the time, equipment, and supplies necessary to perform preventive maintenance procedures are a direct expense to the business. There is also no guarantee preventive maintenance procedures will completely eliminate all major service or repair bills. There are certain parts that will eventually fail because of normal wear and extended use even when preventive maintenance procedures are performed as recommended. Certain other parts and components deteriorate based on age as much as actual use. For example: A new paper air filter is installed in a specialized piece of equipment that is used only 100 hours a year. Instructions may indicate that the filter be replaced every 500 hours or annually, whichever comes first. If the owner attempts to leave the same filter in the engine for five years, the paper will become rotten, rip and allow dirt to enter the air intake system. All parts and equipment will eventually wear out. Remember, preventive maintenance is designed to help protect equipment so it doesn't break or wear out so quickly. Many people are tempted to follow the philosophy "if it is not broke, don't fix it." However, accurate business records have proven over and over the benefits of preventive maintenance. Down time is the period of time tractors and equipment cannot be productively operated while minor or major service or repairs are being made. Consider the loss of revenue when: a crop of alfalfa hay is rained on because the baler was broke down; or a wheat crop received hail damage when the combine engine overheated and seized before the thunderstorm because the radiator was plugged with chaff. Repairs will be expensive, but the lost profit potential from the crop damage may far exceed the cost of preventive maintenance. ## Causes of Agricultural Equipment Breakdowns and Failures Major causes of equipment failures include: 1. Part wear due to dirt, grit, and friction. 2. Extreme hot and cold temperatures. 3. Moisture in the wrong places. 4. Physical damage. 5. Improper operation and use. 6. Improper adjustment. 7. Neglected service and maintenance. A few failures may be caused by design defects and/or defects in the material and workmanship of the original equipment. However, manufacturers are constantly striving to improve and update their products and ensure quality control. Many breakdowns and failures can be prevented, or at least major damage can be decreased by regular preventive maintenance procedures and checks. Regular preventive maintenance procedures should be performed on all the engine and equipment systems which may include: * Fuel Systems * Air Intake and Exhaust Systems * Engine Lubrication Systems * Power Trains System and Component Parts * Cooling Systems * Electrical Systems (including electronic control and monitoring systems) * All Grease and Lubrication Systems * Hydraulic Systems * Tires, Wheels * Steering and Braking Systems * Operator's Platform, Cab or Enclosure * Additional Specialized Parts and Accessory Systems ## Use of the Operator's Manual Preventive maintenance procedures performed on the various systems include: 1. Checking or inspecting systems by looking, listening, feeling, or smelling for abnormal situations. 2. Cleaning equipment or systems of dirt, mud, manure, chaff, stalks, etc. 3. Lubricating linkages and friction points with oil and grease. 4. Changing or replacing worn or damaged "consumable parts," filters, fluids, oils, etc. 5. Adjusting linkages and component parts to compensate for normal wear and varying crop and operating conditions. 6. Refilling fluids to recommended levels. 7. Draining condensation and other sediments from tanks or reservoirs. The first step to understanding and performing these preventive maintenance procedures is to first understand the operation of the basic systems, identify basic parts, and be able to recognize and/or determine the normal operating conditions. Basic information is usually provided in the operator's manual which is supplied with each piece of equipment from the manufacturer. If the original operator's manual has been lost, or the equipment was purchased used, a new copy can usually be ordered from the equipment dealer at a very minimal cost. Normally, if parts and supplies are still available for older tractors and equipment, the operator's manual is also still available. Additional information on the specific operation and service of basic engine and equipment systems are discussed in other student topics in this series. Specific checking, cleaning, lubricating, replacing, adjusting, refilling, and draining procedures are outlined in the operator's manual. Put another way, the operator's manual tells the person performing the preventive maintenance: 1. What to do 2. When to do it 3. Where to do it 4. How to do it 5. Under what conditions to promote safety 6. Why do it ## Types of Preventive Maintenance and Recommended Procedures The different types of preventive maintenance are actually based on when the maintenance is to be performed as much as what maintenance procedures are performed. The types of preventive maintenance are classified as field maintenance, routine daily maintenance, periodic maintenance, and storage maintenance. **Field maintenance** is any service, minor repair, adjustment, or cleaning performed by the operator "as needed" or "as noticed" during the normal course of tractor or equipment operation. Examples may include: * Cleaning the radiator screen of chaff several additional times a day in extremely trashy conditions. * Adjusting the tension on a slip clutch and drive belt as the size of windrows change from one field to the next. Conditions that may indicate that field maintenance, further shop maintenance, or repairs are needed may include: * Unusual or increase of vibration or movement. * Lack of response to controls or linkages. * Alarms, warning lights, horns, and LEDs activated. * Abnormal instrument panel gauge readings. * Change in exhaust color or sound. * Engine pulling down. * Unusual noises. * Unusual smell. **Diagram:** | | --- | | Exhaust Smoke | | Horns, lights, alarms, LED displays | | Vibration | | Unusual Noises | | Odors | **Routine daily maintenance** is any regularly scheduled 5 or 10 hour interval service, maintenance, and operational checks performed before and during the course of the normal work day. These may be referred to as the "every morning, noon, and evening" routines that are repeated daily. Routine maintenance procedures are usually the responsibility of the operator and may only take several minutes to perform. Examples of routine daily maintenance procedures may include: * Checking all fluid levels. * Cleaning air intake screens and precleaners. * Checking air filter indicators. * Cleaning windshields, steps, and platforms. * Checking tires pressures and wheel lug bolts and clamps. * Lubricating scheduled grease fittings and oil cups. * Checking for loose, missing, or broken parts and safety shields. * Checking operation and condition of all warning lights and safety equipment including SMV emblem. It is a good habit to repeat the same steps daily. Everything becomes routine and it is easier to make sure all scheduled procedures are performed. **Diagram:** D D D D GD 10 D **Periodic Maintenance** is any scheduled service, maintenance, and operational checks performed usually in multiples of 10 hours. Common periodic intervals are 50, 100, 250, 500, and 1,000 hours; or weekly, monthly, bimonthly, and seasonal if equipment is operated less than approximately 50 hours a week. In the course of a 50 hour week, the 10 hour routine daily procedures should be performed 5 times and the 250 hour procedures twice within the 500 hours, etc. There are certain seasonal and annual procedures that are recommended regardless of the number of hours equipment is actually used. Periodic maintenance procedures are usually more complex and may require from several hours to a full day to perform. Examples of routine daily maintenance procedures may include: * Changing engine oil and filters. * Flushing coolant system and replacing antifreeze, coolant filters, and thermostats. * Repacking wheel bearings. * Checking battery electrolyte levels and cleaning connections. * Lubricating scheduled grease fittings and oil cups. * Changing hydraulic and power train fluids and changing filters. * Changing and/or cleaning air filters, precleaners etc. * Draining sediment and changing fuel filters. * Checking and adjusting operating pressures of lubrication and hydraulic systems. * Checking and adjusting steering, braking, and shifting linkages, etc. * Checking and replacing belts and hoses. * Checking torque of lug bolts, frame bolts, clamps, etc. * Checking and adjusting valve clearance. * Checking and adjusting fuel systems. The question may be asked, "We are only a day away from being finished planting a crop and it may rain. According to the speed-hour-meter and the operators manual, it is time for a 250 hour preventive maintenance check and engine oil change. Do we have to stop this afternoon and change oil and perform the other procedures?" The answer is normally "no." If all other regular periodic and daily maintenance procedures had been performed as scheduled and all systems were OK, it should be safe to extend the operation a few hours. Recommended intervals and procedures are based on average conditions and wear data collected by the equipment engineers during design and testing. The operator's manual may suggest the service intervals be shorted accordingly if equipment is operated in severe conditions. In this case, it may be safer to go ahead and perform the preventive maintenance procedures and risk the chance of rain rather than a major failure. **Storage Maintenance** includes the steps and procedures that must be followed before placing a tractor or other piece of equipment into off-season storage when not in use. Off-season storage may be for as short as several weeks to as long as from one crop season to the next. Some specialized equipment is used for only a month or less and remains in storage during the rest of the year. Storage maintenance procedures help to: 1. Ensure the equipment is field ready for the next anticipated use season. 2. Allow time for scheduling and performing additional major repair and reconditioning jobs before the next rush season starts. 3. Help to slow depreciation by controlling rust, corrosion, excessive paint fading, and other damaging effects of time and weathering. Storage maintenance procedures usually include performing all regular scheduled periodic maintenance procedures as needed at the time and/or: * Cleaning the equipment. * Changing engine oil and filter. * Making a detailed list of all repair and replacement parts and obtaining them early. * Performing all repairs or scheduling adequate time before the next season. * Repacking wheel bearings. * Completely lubricating equipment. * Draining fuel and/or adding conditioners to fuel systems. * Changing hydraulic oils and filters and/or adding additional moisture and corrosion inhibitors. * Draining and flushing the coolant system and adding new antifreeze and conditioners. * Releasing tension on belts and chains. * Coating exposed metal wear surfaces with soft paint or light grease. * Moving equipment inside a building or to a outside storage location. * Removing and storing batteries in a cool dry place. * Removing extra ballast. * Lowering air pressure in tires. * Blocking tires off ground. * Installing all safety stands and latches. * Relieving all pressure trapped in hydraulic hoses and cylinders. * Coating exposed shafts of hydraulic cylinders with a light film of grease. * Blocking clutches in the disengaged position. * Taping over or plugging intake and exhaust openings. * Taking necessary steps to control damage from birds and rodents. * Removing key to prevent unauthorized starting. * Covering equipment with tarp or other protection if stored outside. Some instructions may recommend waiting until the equipment is brought out of storage before completing some of the periodic maintenance procedures. For example: If the equipment is going to be stored for longer than several months, a new paper air filter may start to age and deteriorate just from the moisture in the air and shorten its useful life. These lists are not complete and this student topic is not intended to provide specific instructions on how to perform each procedure. Items will vary from equipment to equipment, from manufacturer to manufacturer, with the weather, and with the storage and operating conditions. Procedures may even change between two pieces of equipment of the same year, make and model when different accessories or add-on features are installed. Specific instructions are listed in the appropriate operator's manual for each procedure as well as recommendations for placing and removing equipment from storage. ## Periodic Oil Sampling One of the newest items added to the list of preventive maintenance procedures is periodic oil sampling. Under this program, an oil sample is collected from the engine, power train, and hydraulic oil reservoirs on regular intervals. The samples are drawn from the reservoirs by a small hand pump after the equipment has been started and is at normal operating temperatures. These samples are sent to a testing laboratory which analyzes the oil for the different types and amounts of contaminants and wear particles. This program has been adopted by most major engine and equipment manufacturers and oil companies. **Diagram:** ☑ XYZ Company 1111 Anyroad Anytown, USA 44444-4444 John Q. Farmer Progressive Farms RR3 Smalltown, USA 11111-1111 Sample Date | Total Hours | Hours on Oil ---|---:|---: 01-01-91 | 1701 | 100 Test Date | ---|--- 01-05-91 | Equipment Number - 10 Model Number - 1010 Serial Number - 123456789 Compartment - Engine Oil Brand/Weight - XYZ 10w40 Sample Label Number - B-109 Lab Control Number - 105-931-A Overall Sample Evaluation - Reportable Results & Recommendations: Sample shows trace of glycol from antifreeze. Copper is high, sodium is high. Oil is thinner than the grade reported in use, may be diluted with diesel fuel. Flush system if possible, change oil and filter and resample in 50 hours. Oil Condition/Contaminants: Elements: Concentrations in PPM | | | ---|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---: CU | FE | PB | AL | SI | MO | NA | | W | F | G | ST | OXI | NIT | SUL | APP | 46 | 61 | 09 | 03 | 07 | 25 | | | | | | | | | | | AL = ALUMINUM PB = LEAD CR = CHROME CU = COPPER FE = IRON MO = MOLYBDENUM SI = SILICON SOOT = SULPHUR PRODUCTS POS = POSITIVE NEG = NEGATIVE OXI = OXIDATION NIT = NITRATION G = GLYCOL A = ANTIFREEZE F = FUEL W = WATER VIS = VISCOSITY Engine and equipment manufacturers have supplied oil testing laboratories and equipment service centers with information about the types and amount of the different metals, alloys, and other materials used to make the different engine and power train parts. Also provided are wear tables which contain information concerning the rate certain parts will wear away under normal conditions. Oil companies have supplied information about the types of oils and chemicals used to make the fuels, lubricating oils, greases, and other additives. When the owners or equipment service centers send in the oil samples, they include information such as: the total number of hours the equipment or engine has been used and under what conditions; hours since last oil and filter change; amount of oil added since last oil change; brand and type of oil and additives used; and as much information about any service and repair procedures performed since last sampling. A data bank or information file is started for each piece of equipment or engine tested. After several periodic tests, a service technician can analyze the information to see if any trends are developing. This is compared to the "normal" information supplied by the equipment manufacturers. The more information that is available the more accurate the analysis will be. Oil samples are tested for: 1) wear analysis, and 2) chemical and physical properties and/or conditions of the oil. Wear analysis monitors machine wear by identifying the different metal elements and alloys in the oil. By measuring the amounts of copper, iron, chromium, aluminum, lead, molybdenum, etc., the technicians can determine which components or parts are wearing faster than normal. For example: Excessive silicon (sand or dirt), chromium and iron in engine oil and in certain proportions may indicate that dirt is entering through the air intake system because of a faulty air filter, leaky hose or connection. This has probably resulted in excessive piston ring and sleeve wear. Higher than normal amounts of aluminum and lead in certain engines may indicate early rod and main bearing failure and the engine should have an immediate overhaul. Certain other tests can detect trace amounts of water and antifreeze in the oil and may indicate internal coolant leaks. Excessive diesel fuel in the engine oil may point to faulty injector nozzles and/or internal injector pump leaks. Additional procedures can determine the amount of other contaminants such as soot, sulfur, oxidation, and nitration by-products which can indicate poor compression, combustion, or improper engine operating speeds. Similar tests can also analyze the hydraulic oil and determine the condition of the power train and hydraulic systems components. Periodic oil sampling can help minor repairs remain minor and even major repairs remain as minor as possible. For example: A normal engine overhaul with labor and "soft parts" will cost approximately one-half of what a major engine overhaul with labor and "hard parts" will cost after an engine has failed. A soft parts overhaul scheduled and performed when wear analysis indicates it is needed may include labor and only those wear parts such as pistons, rings, sleeves, bearings, gaskets, bushings, and normal crankshaft grinding and valves reseating. A hard parts overhaul may require all soft parts plus a new or rebuilt crankshaft, camshaft, or connecting rods; line-boring and/or cylinder boring; and additional parts that were damaged because the owner or manager had followed the "if it is not broke, don't fix it routine." When the engine broke, it "broke" major parts that normally are not considered replacement items. Periodic oil sampling also allows the owner or manager to: schedule and reduce downtime for planned repairs, and to monitor and improve other preventive maintenance procedures. For example: If silicon, piston and sleeve wear continues to show up in sample results, closer monitoring of air filter cleaning and/or replacement procedures, changing the brand of air filters used, or other improvements may be required. ## Preventive Maintenance and Service Records Just as important as performing the preventive maintenance procedures is recording when the procedures were done, recording any abnormal conditions that were noticed, and notifying the proper person so additional repairs can be made. For example: An operator had been performing the routine daily checks every morning and the periodic maintenance checks weekly. He or she noticed that the fan belt was becoming worn and the cords where exposed. However, the operator did not replace the belt, or inform someone that the belt needed to be changed. The radiator fins were damaged when the belt finally broke. Properly kept service and maintenance records help to ensure all procedures are performed as needed and repairs are made. They will help the agricultural business owner or manager schedule the next service interval or needed repairs with other anticipated shop and field work. Proper records may increase the trade-in or resale value of the tractor or equipment by verifying to the prospective buyer that it has been properly maintained and is in excellent repair. Proper service records will help the owner or manager to more accurately develop an annual repair and maintenance expense budget. Service records will help provide information for the periodic oil sampling program and verify trends that may be developing. Proper service records may also help the agricultural owner or manager decide when to sale or trade equipment. **Diagram:** | | | | --- | --- | --- | | TRACTOR | 10 HR | 50 HR | | SERIAL # 11, 222, 335 | SPECIFIC PROCEDURES LISTED IN OPERATORS MANUAL | | UNIT # 5 | PLUS OTHERS THE OWNER MAY LIST | | MODEL # 5555 | 20 HR | 100 HR | | CONSULT OPERATOR MANUAL | | | | FOR 250 HR & YEARLY | | | | | | | | --- | --- | --- | --- | | HOURS TODAY | DATE | 1-15-92 | 1658 1758 | | HOURS SINCE LAST SERVICE | 98 | 2-14-92 | 100 | | NEXT SCHEDULED SERVICE DATE | 2-15-93| | 16 | | WHO PERFORMED SERVICE | Fred | | John | | COMMENTS | ADDITIONAL COMMENTS | | --- | --- | | Alt. belt will need replacing next service | ON BACK | | Battery was low | | | | | Shown is an example of a service record form that could be neatly stored in a notebook in the shop or service center. Service record forms may also be included in some operator's manuals. Software programs are available for those businesses that have computers. Forms or data base templates should be as simple as possible, yet provide a place for all important information to be recorded. Information should include: * Description of equipment including model and serial numbers, business unit number, and extra equipment or accessories added * Date service was performed * Who performed the service * Total number of hours on the equipment speed-hour-meter when service was performed * Total number of hours since last service * Date and/or hours of next anticipated service or maintenance interval * Any unusual noise or conditions or potential problems the operator and/or person performing the service may have observed and under what circumstances Some service records may also include a place to list all parts and supplies used. ## Acknowledgements Dr. Joe Muller, Curriculum Specialist, Instructional Materials Service, developed and organized the information in this topic. Mr. Chuck McHam, Graduate Assistant, Department of Agricultural Education, Texas A&M University assisted. Mr. Rodney Schmalriede, Graduate Assistant, Department of Agricultural Education, Texas A&M University, developed the student activities. ## References: * Fundamental of Operation: Preventive Maintenance, Deere and Company, Moline IL. * Tractor Maintenance, American Association for Vocational Instructional Materials, Athens, GA. * Jacobs and Harrell, Agricultural Power and Machinery, McGraw Hill Company, New York, NY. * Scheduled Oil Sampling, Caterpilliar Incorporated, Peoria, IL. * Machinery Maintenance, Deere and Company, Moline, IL.