July 2002

Maintaining Equipment By John Bartok

Equipment maintenance is an important part of operating agreenhouse or nursery business. The development of new machines and thedifficulty in obtaining good labor has led to the use of more equipment ingreenhouse operations.

The following episode I observed while on a greenhouse tourillustrates the cost of poor maintenance and the need for a preventivemaintenance program. This type of occurrence is common in the horticultureindustry, as maintenance is generally not given high priority.

It was 12:45 p.m., and the 7-person crew was just fallinginto a pace transplanting bedding plant plugs into flats on a belt conveyor. Atthe rate of 250 flats per hour, this crew would finish filling the 26- x 96-footgreenhouse by the 4:30 quitting time.

Suddenly, the flat filler stopped dead without warning, butthe motor was still running. The crew chief started looking for the troublewhile everyone else took a break. After retrieving the frayed 36-inch V-beltfrom under the machine, he headed for the storage room hoping to find areplacement. After a 15-minute search without any success, he decided to sendsomeone to the hardware store. The 30-mile trip and the time to install the newbelt would probably take most of the afternoon so he decided to send the crewhome. A 1,000-flat production loss such as this can have a significant effecton meeting production schedules.

Assign equipment maintenance to a responsible person

Someone that is mechanically inclined should be given theresponsibility for maintenance. In small operations, it may be the grower alongwith his many other responsibilities. In larger operations, freeing up oneperson for part of each day or week may be enough. When your business grows tomore than 10 or 15 employees and your equipment list gets longer, it is time tohire a full-time person. Vo-ag or Vo-tech graduates who have majored inmechanics have performed well for some growers.

Provide a place to work and a good set of tools

For small operations where vehicles and equipment areserviced on the premises, a work area in the headhouse or in a garage may besufficient. For larger operations, a separate building is desirable. The areashould be near the growing area, have good access for vehicles and contain bothelectricity and water. Provisions should be made to heat the work area duringcold weather. It is convenient to store tractors, electric carts and othermobile equipment in an adjacent, unheated, machinery storage area.

Shop size. The size of the shop should be large enough to accommodate the equipment that will beserviced. If trucks and tractors will be maintained, an open floor area anddoor large enough for access is necessary.

Space for floor-mounted equipment, such as a drill press,table saw and welder, is also needed. A good arrangement is to locate a shopfacility in one end of a storage building.

Shop layout. The layout of your shop should be flexible to accommodate the equipment that willbe serviced. An area should be provided for the day-to-day jobs. Oil, grease,air and water should be convenient to this area for servicing vehicles. Arepair bay is convenient if equipment is to be disassembled and overhauled. Itshould be well-lighted and have space for storing the parts that are removed.

Perhaps the greatest weakness of most maintenance shops isthe lack of an organized arrangement for the hand and power tools. Specific areas should be designated for welding, woodworking, plumbing and electricalwork, with equipment associated with these jobs located nearby.

Shop equipment.Portable tools that have the greatest use in a maintenance shop include a 3/8-and 1/2-inch electric drill; a sander; 3/8-inch, battery-powered drill/driver;a saber saw; 7 1/2-inch circular saw; and a compressor. The compressor can beused to power a wide selection of air tools and spray equipment.

Stationary tools that are worth owning include a 6-inchbench grinder, drill press, 10-inch radial arm or table saw and a metal bandsaw.

Where repairs include metal work such as fabrication or thecutting of steel, both an alternating current welder and an oxyacetylene welderare needed. Courses on proper welding techniques are available through avocational agriculture or industrial arts program at local high schools.

Consider safety when planning and using the shop. Place amulti-purpose, dry chemical (A:B:C) fire extinguisher near entrance doors andthe welding area. Protective clothing, including safety goggles and steel-toeshoes should be worn when working on equipment.

Keep a good supply of spare parts on hand

To keep equipment down time to a minimum, keep on hand asupply of hardware, short-life replacement parts and specialized parts that maynot be readily available. Assortments of small hardware items, such as pins,stove bolts, cap screws, washers, etc. are packaged in convenient 20- to30-drawer cabinets that sell for $15-25. Larger bolts, pipe fittings, etc., areavailable individually or in box lots at most hardware stores and equipment suppliers.

Most of the equipment used in the horticulture industry iswell-built, requiring only routine maintenance. When purchasing a new piece ofmachinery, it is best to review the owner’s manual and inspect themachine to identify parts that are likely to fail first. Items such as V-belts,drive chains, sprockets and oil and air filters can be purchased locally ifavailable or ordered from the manufacturer.

Small items are best stored in labeled bins on racks.Plastic bins are available in several sizes to hold loose materials. Largerparts are normally stored on shelves. Good lighting in the storage area willspeed identification of the parts.

Maintenance records prevent failures

Keeping good records aids in scheduling maintenance. Manymanufacturers supply a form to check off the date and service performed. Abetter method is to use a computer. You can set up your own program or purchasecommercial software. Each week a printout is made of the machines needingservicing.

In setting up the schedule, follow the recommendations ineach operator’s manual. Enter the various jobs to be performed under the”hours of operation” headings. Then check off the intervals ofservice after they are performed.

Watch and listen

Employees should be encouraged to watch and listen forpossible problems as they operate the equipment. Worn belts, loose chains, lowtire pressure, frayed hoses and electrical cords, etc. are signs ofpending trouble and should receiveimmediate attention. Indicator lights and dials are placed on machines to makethe inspection easier.

Keep all service manuals together

A considerable amount of time can be saved if alloperator’s manuals are kept in one location. A file cabinet in the workshoparea gives convenient access. Organize them by type of machine and keep them inindividually labeled files.

Service Tips and Guidelines

The following apply to most gasoline- and diesel-poweredvehicles and are general in nature. Individual recommendations on a particularvehicle can be found in the manufacturer’s service manual or in one ofthe general service manuals.

Frequent air cleaner servicing is important to avoid wear ofthe cylinder and valves. Servicing should be more frequent if the engine isoperated in dusty conditions such as field work.

Change oil regularly.Oil loses its lubricating and cleaning qualities as it gets dirty, and itsadditives wear out. Select oil to meet weather and operating conditions.

Several different oil/gasoline mixes are used for 2-cycleengines. Keep a gas can for each engine, and identify the mix ratio and numberof ounces of oil/gallon of gas needed.

Check coolant levels daily. Replace coolant every two years, as it may become acid and full ofcontaminants. Before winter, measure freeze protection level.

Check fan belts for tightness and wear. A belt that’s too tight puts an extra load onbearings. A loose belt allows slippage and may not operate the machine at thecorrect speed.

Keep battery terminals clean and free of corrosion.Neutralize acid deposits with a baking soda and water solution. After cleaning,coat terminals with grease or silicone spray. Check cables for cracks or wear.

Follow manufacturer’s recommendation for servicingignition systems. Condenser, points, plugsand ignition wires may need to be cleaned or replaced.

Most manufacturers recommend a daily check on oil levels,including engine, transmission, power steering and differential.

To increase tire life, inflation level should be checked frequently.Under-inflation reduces tire life. Over-inflation causes excessive wear in thecenter of the tire.

Use the operator’s manual as a guide for lubricatingthe vehicle. Most manufacturers provide a lubrication chart that indicates thefrequency of lubrication. Typical intervals are 5, 10, 25 and 50 hours.

Materials Handling and Processing Equipment

Storage. Most of thevehicles and equipment used in the production of plants are not in useyear-round. Some of it only sees use for a few days a year and is then put intostorage to make room for other equipment.

Clean the exterior and component parts of soil. These cancollect moisture and cause rust to form. A shop vacuum works well for thisoperation. If the machine is outside, air from a compressor can be used but besure to wear a dust mask and safety glasses.

Service engines as noted above, and drain the fuel tank oradd fuel stabilizer.

Electric Motors.Although electric motors require less maintenance than other types ofequipment, some periodic servicing is required. Unless the motor is operatedunder severe conditions such as dust or outdoors, a once-a-year servicing isadequate. Caution — shut off power to the motor before working on it.

Typical servicing includes: 1) Cleaning dust and dirt fromair passages and cooling surfaces. A heavy dust build-up will result inoverheating and break-down of the wire insulation; 2) checking bearings forwear, excessive endplay or drag. Misalignment of pulleys or over-tightness ofV-belts can cause the bearings to wear or the motor to overheat. Alignment canbe done with a straight edge placed against the face of the pulleys. To get theproper belt deflection at mid-span, multiply the distance between shafts byone-sixty-fourth of an inch; 3) Checking wiring for worn or frayed spots andreplacing if necessary. Clean switch contacts with a contact cleaner or veryfine sandpaper. Replace worn brushes and springs in wound-rotor motors.

Hydraulic Equipment.Regular maintenance keeps hydraulic systems operating without breakdowns. Itincludes keeping the equipment clean, checking for leaks, proper fluid leveland proper operation.

Always remove the pressure from the hydraulic system beforedoing any servicing.

Change the fluid and service filters at the interval recommendedby the manufacturer. Clean dirt away from fill pipe before adding oil.

High-pressure fluid leaks are very dangerous. Fluid thatgets under the skin must be surgically removed to avoid gangrene.

External leaks from pipes and pumps should be fixed to avoidlow fluid level and to prevent pollution of the ground water. They can also letair into the system resulting in spongy action of the cylinders.

Inspect operation of the valves frequently for leaks andpoor operation. Springs or seat may have to be replaced.