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Troubleshooting Pumps & Unloader Valves

Troubleshoot common issues faced with pumps & unloader valves

Low Pressure in the Pump

Problem. Probable Cause. Solution. Pump runs normally but pressure is low. Pump is sucking air. Check inlet circuit and possibility of air ingress. Stuck valves. Check & clean, or replace if necessary. Unloader valve faulty. Check & replace if necess

Pressure Fluctuating/ Not Steady

Problem. Probable Cause. Solution. Pressure Fluctuating & not Steady. Jammed valves. Check & clean out if necessary. Pump is sucking air. Check inlet circuit and possibility of air ingress. Worn packings. Check & replace if necessary. Worn nozzle. Ch

Pump Losing Pressure After Some Period of Use

Problem. Probable Cause. Solution. Pump builds proper pressure, but starts dropping after some time of use. Worn check valves. Check & replace if necessary. Jammed check valves. Check & replace if necessary. Worn unloader valve seat. Check & replace

Noisy Pump/ Making Weird Sounds/ Knocking Sound

Problem. Probable Cause. Solution. Pump is more noisy than usual/ Making weird sounds. Inlet plumbing of improper size. Check & replace if necessary. Broken spring of the discharge valve. Check & replace if necessary. Worn. bearings. Check & replace

Presence of water in oil/ Oil looking milky

Problem. Probable Cause. Solution. Presence of water in oil (Oil looking milky). Worn oil seals. Check & replace if necessary. High humidity in the air. Check & change oil more frequently. Worn packings. Check & replace if necessary. Please reach out

Water leaking from the pump

Problem. Probable Cause. Solution. Water dripping from between the pump head & pump body. Worn O-ring plunger retainer. Check & replace if necessary. Worn packings. Check & replace if necessary. Water leaking from the piston (spring holder) or valve

Oil leaking from the pump

Problem. Probable Cause. Solution. Oil dripping from between the pump head & pump body. Worn oil seals. Check & replace if necessary. Worn packings. Check & replace if necessary. Oil leaking from the shaft side of the pump. Shipping cap instead of ve

Pressure fluctuating when letting go of gun trigger

Problem. Probable Cause. Solution. Pressure fluctuating when letting go of gun trigger. Leaky gun and/ or pressure hose. Check O-rings in the gun and look for holes in the hose. Replacement/repair as required. Worn O-rings in the pump head. Check & r

Excessive water return in the bypass at the operating pressure

Problem. Probable Cause. Solution. Excessive water return in the bypass at the operating pressure. Nozzle size is too small. Please refer nozzle size calculator at 1/4-in Quick-Connect Pressure Washing Spray Nozzles, Set of 5. Worn poppet and/ or sea

Pressure gauge fluctuating when the gun is on

Problem. Probable Cause. Solution. Pressure gauge fluctuating when the gun is on. Dirty unloader valve. Clean valves and lubricate parts. Worn packing seals in the pump. Check & replace if necessary. Worn check valves in the pump. Check & replace if

Very high pressure in the hose line when the gun shuts off

Problem. Probable Cause. Solution. Very high pressure in the hose line when the gun shuts off. Excessive tightening of the spring in the unloader valve. Turn the unloader valve counter- clockwise to reduce the pressure setting in the spring. If that