Vacuum excavators can be seen on almost every underground infrastructure construction project. It’s no wonder because these machines, whether chassis- or trailer-mounted, provide a safer alternative to digging with a hydraulic excavator and faster alternative to digging by hand.
These benefits amount to nothing if the equipment is down, and just like with any other pieces of construction equipment, the key to optimal uptime is proper maintenance. Here are some tips to keep your vacuum excavation equipment running in peak shape.
While some of these items seem obvious, it is seldom done and this is a good reminder that some major problems can be averted with these minor steps.
When it comes to the chassis, be sure to check the date of the last complete chassis service. Also, check all fluid levels, visually inspect all lights and visually inspect all tires for wear or damage. In the cab, make sure that there are no engine or other warning lights on the dash.
With the vacuum system itself, it is best to perform a full walk around to inspect for leaks, damage and complete an inventory of all required parts and pieces. Inspect all hoses for wear including the boom hose, and the entirety of the wash hose. Inspect and clean the entirety of the filtration system on both the vacuum and water pump sides. This includes the cyclone and vacuum filter and bear in mind that the cyclone can sometimes bridge with debris so be thorough. Also, you’ll want to clean out the inline water pump filter. Also, it is best to fully clean the unit to create the best first impression when arriving at the job.
Fluids are the blood that keeps your vacuum excavator running. Be sure to check the dates of the last oil changes on the blower, water pump and hydraulic system. Inspect blower oil levels and the visual quality of that oil. The oil should be clear with a yellowish tint. Milky or dark oil needs changed and the cause for these oil conditions needs to be uncovered. Dark oil usually means an impending internal blower issue. Milky oil usually means contaminated lubricant.
Also be sure to inspect water pump oil level, hydraulic oil level and quality, and the glycol system levels if applicable.
Greasing is a fairly easy step, ensure all required grease zerks have been hit. If not, get them greased.
Lastly, test operate all electrical functions, including lighting, blower engagement, pump engagement and test fire the blower. Electrical issues are often simple to fix at the shop, but less so in the middle of a job. Also test all functions off of the wireless remote. Ensure the remote is charged (or has new batteries if applicable). Test run the boom, extend it and retract it, and run it through its entire range of motion.
Tips During Operation
The operator should continually monitor hydraulic temperatures to ensure appropriate cooling is occurring. When you cycle a load at disposal, fully inspect vacuum filtration. Obviously respond to any leaks or warnings if the system is either performing improperly or alerting you to do so.
Post Project Inspection
We highly recommend that at the completion of a project, the operator completes the full inspection protocol so that when they are called out again, they know they are good to go. If you wait until the phone rings, many times items are left undone because you are in a rush to get to work.
If a unit is brand new, we recommend that oils are changed at 50 hours. This includes the blower oil, water pump oil and hydraulic oil, as well as the transfer case oil if applicable. After this initial cycle, service every 200 hours is a good number. It’s also important to use the manufacturer’s recommended fluids.
Normally, you will not need to adjust these intervals for projects or for the changing seasons. If the operator can adhere to these intervals in all seasons and applications, they will avoid excessive wear.
The operator should be able to do all of the visual inspections and walk-around and should be able to diagnose the critical components of the unit. It is much more convenient for the physical services to be done in a shop. What is optimal and what is practical are different. Uptime is critical with all equipment and these units have multiple items that could act up. The operator is the only one there usually when it happens, so the more able that person is to get the truck back into service, the better it is for the operating company and the clients. The operator cannot leave the job unless it is a last resort, or you could potentially lose the client. Properly training the operators to be as adept as possible with the equipment is essential with these units.
Anything that is still within the warranty period and is significant should be performed by authorized personnel, both for quality and warranty reasons. Any chassis type work related to computers, codes, engines and transmissions should be completed by authorized technicians. Other examples of failures where the repairing personnel should be factory trained would be blowers, PTO systems, transfer cases and significant electrical issues. Most vacuum system manufacturers do not have service in each city, so most of the critical diagnosis is done over the phone, and if it is critical, it is usually most practical to either replace the failed component or ask the manufacturer to tell you where to take the unit for evaluation.
As stated above, you cannot afford to send the unit somewhere every time something goes awry. You should be able to call someone and get a solid diagnosis, and then assistance with a go forward plan including sourcing parts.
This article was compiled by staff at Trenchless Technology Canada, a sister publication to Utility Contractor, with input from Rival Hydrovac.