Maintaining Your High Pressure Water Jetter
February 18, 2014
Whether your jetting unit is used once a month or four times a day, these routine maintenance tasks need to be conducted on a regular basis, and you don’t have to be an engine mechanic or pump expert to handle most of it. All operators who come into contact with the unit need to be trained and familiar with not only the operation and functions of the machine, but also in the service checklists to ensure that the system is performing properly and operating safely.
All high-pressure jetting units are similar in design and essentially differ only in configuration and size required to produce pressurized water at various pressure (PSI) and water flow (GPM) outputs. Whether the jetting unit is a small cart machine, trailer-mounted unit, truck-mounted unit or part of a combination machine, each contain five primary components that require preventative maintenance. Every jetting unit consists of a high-pressure water pump, power source (auxiliary engine or hydraulically driven motor), a hose reel with high-pressure jetting hose, a pressure relief/unloader valve and a water control (on/off) valve. When personnel understand the theory and function of all components, then routine maintenance is achievable on any size jetting unit.
With increased Department of Transportation (DOT) regulations, a checklist specific to high-pressure jetting equipment maintenance should be added to the operator’s daily inspection responsibilities. Operators should reference the manufacturer’s owner manual for specific maintenance requirements, as well as the separate manuals for the pump and engine.
Daily Maintenance
• Check Engine Oil: Consult Engine manual for recommended oil specifications.
• Check High-Pressure Pump Oil: Most high-pressure pumps will have a sight-gauge or dip stick, reference pump manual for oil specifications.
• Check & Clean Water Filters: All pumps like clean water, so it’s imperative to clean filter systems before every use. When filling from a hydrant, be sure to flush it first to remove any sediment and debris before filling tank. Most jetting machines will have a dual filtration system consisting of a sock filter for the water tank and an inline micron filter before the pump.
• Check for Any Leaks: Before running your jetter, inspect inlet plumbing, pump, and water systems for any leaks that could be a safety issue and detract from the unit’s performance. Additionally, inspect engine, hydraulic systems and hoses for oil and fuel leaks.
• Check Tire Inflation: Constant weight variance due to fluctuating water levels can affect the pressure in your truck or trailer tires, so make sure to check the inflation before every use to the recommended PSI listed on the tire for maximum load capacity.
• Check Trailer/Truck Lights: Check all Stop, Turn, Brake, and Hazard lights.
• Check Trailer Chains & Hitch Connection: Always double check that trailer hitch is connected properly using the appropriate size ball, and make certain that safety chains and break engagement are connected from the trailer to the towing vehicle.
• Anti-Freeze/Winterization: Water freezes at 32 F and any water left within a jetter can cause catastrophic damage in freezing temperatures. Most jetting units will have a recirculation system allowing an anti-freeze solution to be pumped through the pump and plumbing system to prevent freezing. Other units incorporate an air-purge valve to protect against freezing, which allows pressurized air to be introduced thus displacing all the water from the system. NEVER start the machine if you suspect it is frozen and make sure that all operators are proficient with winterizing procedures during cold weather operation to prevent costly damage to your pump and water system. Consult owner’s manual for detailed instructions on anti-freezing and air-purging of jetter as manufacturers employ various methods of winterizing machines.
• Check Nozzles: Nozzles need to be checked for clogged orifices and cleaned on a daily basis. When a nozzle becomes blocked, it changes the dynamics and reduces the efficiency of the high-pressure jetting unit. A clogged orifice or orifices increases the restriction of the water thus increasing water pressure. Excess pressure is relieved by dumping pressurized water through a relief valve back into the water tank, reducing the cleaning ability and productivity of the jetter. Additionally, nozzles bore out and wear over time, causing the pump and engine to work harder to produce desired pressure. Nozzles need to be checked for performance periodically and replaced/repaired as necessary.
Monthly Maintenance
• Check Axles/Bearings: Most wheel bearings will have an easy lube zerk fitting, and if not, remove dust cap and hub to pack bearings with grease. Check brake shoes for wear, and adjust if necessary. Consult owner’s manual for specifics or bring unit to a qualified inspection facility.
• Check Lug Nuts: Torque lug nuts to recommended specifications.
• Grease Engine Stub Shaft: Most engines will have a grease zerk fitting where power is transferred from the engine to the pump’s drive system. These power packs are turning at very high RPMs, which is why they require regular lubrication.
• Check Pump/Engine Drive Belt: When the jetter is off, remove the cover or guard to access the belt, then check to make sure belt is aligned and tensioned properly. Consult manufacturer’s recommendation for the appropriate deflection, and NEVER perform any belt maintenance while the unit is running.
• Check Hydraulic Oil: Consult manual for recommended oil specifications.
• Check Hydraulic Selector: Make sure that hydraulic selector handle moves smoothly, if not, consult manual as some selectors require regular lubrication.
• Check Battery Connections: Make sure that battery terminals and connections are secure and free of corrosion to prevent any electrical damage.
• Grease Hose Reel Bearing: Most jetter manufacturers now offer a Pivot, or Swivel hose reel that allows operators to position the reel system at different intervals, so it is necessary to grease the bearing frequently to prevent undue wear or seizing. Consult owner’s manual for location of grease fittings for reel bearing
• Check Engine Belts: Visually inspect the alternator and fan belts for wear, cracks, or fraying.
• Check Frame: Conduct visual inspection and check all steel frame components for cracks or fatigue, including all welds, seams, joints, etc.
The critical maintenance check of a high pressure jetting unit can only occur during actual jetting operations, and high-pressure jetting hose should be considered a wear item that periodically requires replacement. While the high-pressure jetting hose can be visually inspected for tears, scrapes and damage, some leaks and other defects can only be detected when the machine is running. The operator must constantly be observant for any damage to the hose coating as the reel spools in and out.
Cuts or scraping to the outer plastic coating, blistering or pinhole leaks are indicative of a potentially dangerous hose burst. Most pinhole leaks and blistering will only become apparent when the unit is operating under pressure. If the hose coating has worn or peeled away to expose such flaws, work should cease immediately until the hose has been repaired or replaced. Repair for either of these problems normally consists of cutting out the damaged sections then installing a hose splice or coupler to join the hose back together. Hose can last several months or several years depending on the care and appropriate use by the operator, and a hose guide or “tiger tail” should always be used in most jetting applications.
Just like your vehicle, all jetting units require periodical fluid/filter changes to keep the system’s components running properly. These services include changing the engine oil and filter, pump oil and filter, air filters, fuel filters and hydraulic oil and filters. While most automotive companies recommend an oil change every 3,000 miles, the fluid/filter service on a jetter should be performed every 250 hours of operation or once a year. For those who run their machines more frequently or on a daily basis, fluid/filter changes need to be performed more often depending upon hours of use, conditions of operation and climate factors. Contact your equipment manufacturer and consult the jetter’s pump and engine manuals for detailed fluid/filter instructions and specifications.
Just like any piece of machinery, high-pressure water jetting equipment can last for many years and thousands of hours when serviced and maintained properly.
Ryan Peake is Southeast/Southwest direct sales manager for Mongoose Jetters.