Problem #1: Sudden Loss of Suction
You engage the pump, but the vacuum gauge barely moves. You can hear the pump running, but it's not pulling vacuum. This is the most frequent issue operators face.
What to Check:
1. Check Your Valves: The number one cause of suction loss is an open valve. Walk around the truck and double-check that your intake valve is open and your discharge valve is fully closed and sealed. Even a slightly open discharge valve will prevent you from building vacuum.
2. Inspect for Air Leaks: A vacuum system is a closed loop. Any unintended air getting in will kill your suction.
- Hoses & Fittings: Are all your cam-lock fittings tight? Is the gasket inside the fitting in good condition?
- Manway Lids: Is the primary manway lid on top of the tank sealed tight? Check the wing nuts and inspect the gasket for cracks or wear. A worn manway gasket is a common culprit.
- Piping: Listen for a hissing sound along the truck's piping, which can indicate a crack or loose connection.
3. Check Your Shutoffs: Inspect the primary shutoff inside the tank and the secondary shutoff near the pump. If either is full of liquid or clogged with debris, it will block airflow and prevent the truck from pulling vacuum.
Problem #2: The Pump is Overheating
Your pump is running unusually hot to the touch, or you smell a burning oil scent. An overheating pump is a serious issue that can lead to costly, permanent damage if not addressed.
What to Check:
1. Pump Oil Level: This is the most critical check. Shut down the pump and check the oil reservoir. Low oil levels are the leading cause of overheating. If it's low, top it off with the manufacturer-recommended oil. If the oil looks milky or sludgy, it's contaminated and needs to be changed immediately.
2. Airflow: Vacuum pumps generate a lot of heat and need proper airflow to cool down. Make sure the pump's vanes are clear of dirt, mud, or debris.
3. Drive Belts: Check the tension on the belts driving the pump. A belt that is too loose will slip and create friction heat, while a belt that is too tight can strain the pump's bearings, also causing it to overheat.
Problem #3: Clogged Hose or Wand
You have a strong vacuum on the truck, but nothing is moving through the hose.
What to Check:
1. Look for the Obvious: First, check the end of your suction hose or wand. It's often clogged with rags, roots, or other debris right at the intake.
2. Try Reversing Pressure: If your system is equipped with a 4-way valve that allows you to create pressure, you can try to gently push air back through the hose to dislodge the clog. Warning: Only do this if you are trained on the procedure. Pressurizing a vacuum tank can be dangerous. Start with low pressure.
3. Manual Inspection: If you can't clear it with pressure, you'll have to do it the old-fashioned way. Lay the hose out straight and use a plumber's snake or a solid rod to push eh obstruction out. For sectional hoses, disconnect each section to find where the clog is located.
Problem #4: Valves are Sticking or Leaking
You close a valve, but liquid continues to drip from the hose or fitting. A leaky valve is messy, unprofessional, and can be an environmental hazard.
What to Check:
1. Inspect for Debris: The most common cause of a leaky valve is a small rock, twig, or other debris stuck in the valve seat, preventing it from closing all the way. Open the valve and inspect it carefully, cleaning out anything that's not supposed to be there.
2. Check the Seals: Over time, the rubber or neoprene seals and gaskets inside the ball valves and gate valves can become worn, cracked, or deformed. If cleaning the valve doesn't solve the leak, you will likely need to replace the internal seals.
Problem #5: Strange Noises from the Pump
Your pump is making a new noise you haven't heard before. Listening to your equipment is key to catching problems early.
What to Listen For:
1. Squealing Noise: A high-pitched squeal usually points to a loose or worn drive belt. Check the belt's tension and condition.
2. Grinding or Rattling: This sometimes means debris has bypassed your shutoffs and has entered the pump itself. Shut the pump off immediately. Running the pump with debris inside can destroy the vanes and housing. The pump will need to be flushed or potentially disassembled and cleaned.
3. Loud Knocking: A rhythmic knocking sound could indicate a serious internal problem, such as a broken vane or a failing bearing. This is another "shut the pump off immediately" situation. Continuing to run the pump will cause severe damage.
When to Call for Service
These quick fixes can solve most day-to-day issues. However, if you've run through this list and the problem persists, or if you encounter a larger issue like a loud grinding or knocking from the pump, it's time to call a professional. Give your truck or pump manufacturer a call.
A reliable, well-maintained truck is your most important asset as a pumper. By learning to spot these common issues, you can ensure your rig stays on the road longer and for less cash - ultimately making you more more money.
Looking for a truck that's built to last? Our trucks are engineered for maximum uptime and easy maintenance. Contact our team today to learn how our trucks can help you grow your business at 501-279-0001 or check out our inventory here!
By Riley Reed