Vacuum Truck Maintenance

What You Can Do to Prolong the Life of Your Vacuum Truck
Olivia Day — Oct 01, 2010

When it comes to using a vacuum truck, you not only want full productivity and optimum performance, you also want to extend the productive life of the equipment as long as possible. Insist on high-quality, durable machines. Shortcuts can effectively reduce your overall productivity.

But the machine lasting due to good quality is only one half of the equation. The other half requires some special attention on your part. To get the best performance out of your vacuum truck, prolonging its life is key. By following these important maintenance tips on a regular basis, you will be able to go a long way to achieve the most favorable return on your investment.

General Preventative Maintenance


The most vital areas of preventative maintenance are paying particular attention to correct lubrication of the unit, routine cleaning and upkeep of the hydraulic system. The objective of preventative maintenance is to avoid operation difficulties and extended downtime for costly repairs. Adhere to a regular maintenance schedule and keep detailed records of all maintenance performed. Routinely inspect operating and maintenance records for deviations from normal operating conditions.

Daily Preventative Maintenance

Shut Down at the End of the Day

Shutting down the truck when your shift ends consists of emptying the water system by opening all water system drain-valves and opening the debris body to allow air circulation.

If the truck is being stored longer than overnight, the tailgate should be propped open with the rear door support and the debris body partially raised and blocked.

At times when the truck is going to be stored during temperatures below 32 F, it is important that the water system and debris body are free of water. Lubricating the truck and checking all fluids will also help.

Weekly Preventative Maintenance

Check Fluid Levels and Air Breather

When checking the fluid levels in the hydraulic tank and the blower, ensure that all cylinders are in their retraced position. The fluid level sight-glasses should be half covered. If the levels are low, fill the hydraulic tank with fluid or the blower with oil. If there is frequent or sudden loss of fluid, this could indicate leakage.

Clean the Debris Body

While the debris body is raised, wash it with the water handgun. Start at the upper front corner and work downward and to the rear of the body. Change sides and repeat the procedure. If equipped, wash out the sludge pump attached to the tailgate. Also make sure the debris body float-ball is clear of waste. After the cleaning is completed, run the truck for a short time to remove moisture from the body.

Air & Water Separator Cyclone Inspection

Clean the cyclone screens after inspecting them for an abundance of liquid or debris. Check the plug on the bottom of the cyclone for more debris.

Also be sure to check air access areas, such as intake hoses, nozzles and deflectors, for wear. Wipe away any dirt from the boom enclosure and apply a light coating of grease on the inside edges. Also check for tight connections between intake couplers, nozzles, ball joints, etc., as air leaks will reduce the efficiency of the blower.
 
Monthly Preventative Maintenance
Electrical System
Check electrical wiring and insulation for frays, breaks, corrosion and loose connections.

Body Hoist

Inspect the upper and lower trunnion ends of the cylinder, lifting lever, cross shafts, frame, valve and pump. Inspect all hose lines for damage and hose ends for tightness. Check the cylinder packing (a light film of fluid on the piston rod is acceptable), the mounting bolts for loosening and the pins for holes and wear.

Intake Hose

Wear on intake hoses should be expected, as they are made of rubber and fabric. This wear can be kept to a minimum by using a few good operation and maintenance practices. Inspect the hose frequently to determine where the most wear is occurring. Rotate the hose periodically to reduce wearing in one spot. Rotating the hose 180 degrees, 90 degrees and end-over-end, periodically, will lengthen its life. Minor cracks, punctures and other leaks should be repaired as soon as they are detected to prevent becoming unfixable.

Hydraulic System Service

Contamination: Many hydraulic problems can be traced directly to the hydraulic fluid. It is important that all foreign matter be kept from the fluid. Abrasive-type contamination may cause serious pump wear, malfunctioning of pumps and valves and sludge accumulations within the system.

Commercial Hydraulic Fluid Testing: Hydraulic fluid samples should be taken for laboratory analysis. The sampling should be done based on standards from the American National Standards Institute. Two samples should be taken from the center of the reservoir when the fluid is at an operating temperature. Place them in a clean, dry, glass bottle with a screw-on cap. Label the bottle with the date, type of fluid and model and serial numbers of the machine. Use one sample for laboratory analysis and the other for your own preliminary analysis. The most important analyses are particle count, Spectro-chemical, water content and viscosity.

In-House Hydraulic Fluid Testing: Let your fluid sample set for 20 to 30 minutes to eliminate air bubbles. Hold the bottle up to the light to check for debris in the fluid. Any visible debris is an indication of a severe solid-contamination problem. Common sources of this kind of contamination are component wear, an unsealed reservoir cover or dirty air-breather filters. If the fluid is cloudy, it may be an indication of water contamination. Common sources are inadequate outdoor storage, unsealed reservoir covers or condensation.
A “Blotter Spot Test” may also be performed to test for oxidation. Place a drop of fluid on a piece of white blotter paper. If the blotter remains colorless or develops only a light yellow ring, oxidation is under control. If color develops but is uniform throughout, the fluid is still serviceable but should be checked for correct additive content. If the sample shows distinct rings, the fluid should be changed. If a distinct dark spot remains in the middle, but a lighter color fluid migrated outward in the blotter paper the fluid is about to dump sludge or other byproducts into the system.

Semi-Yearly Preventative Maintenance

Hydraulic Filters

Change the hydraulic filters. To remove the filter elements, unscrew the filters from the filter assemblies’ head and remove the filter element. Throw out the old filters and refill new filters with hydraulic oil.

Yearly Preventative Maintenance

Flushing Hydraulic System

Drain all fluid from the hydraulic tank. Drain the fluid reservoir by removing the drain plug. Fill the tank with fresh fluid. Start the engine and operate all the hydraulic functions. Leave all the hydraulic cylinders in the retracted position and shut down the unit. Recheck the fluid level and add fluid as necessary to bring the level to half way in the sight gauge. Replace hydraulic tank breather.

Seasonal Storage

If the truck is going to be inactive for long periods of time, take the following steps to avoid corrosion in the body and air chamber. Steam-clean the inside of the body. Repaint with a good primer to prevent any corrosive action due to moisture. Rotate the blower monthly by hand, if needed.

By following these simple procedures, you should be able to effectively impact the value and return on your own important equipment investment.

Olivia Day is a writer with Whitemyer Advertising, Zoar, Ohio.

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