Basic Repair Tips for a Pressure Washer Pump

a pressure washer
  • 2-6 hours
  • Beginner
  • 20-100

Pressure washer pump repair does not require the help of a professional unless dealing with serious damage. Usually, the cause of the failure is improper operation or installation. When the pump is not working properly, read on for pressure washer pump repair tips.

Oil Leaks

Oil leaks can occur between the pumping section and the crankcase. This is usually caused by worn out crankcase piston rods and seals as well as worn out plunger retainer o-rings. If this occurs, simply replace the rods and seals and o-rings with new ones.

Failure of Pump to Prime

This is usually caused by trapped air inside the pump. To fix the problem, simply remove the discharge hose and flood the suction hose with water. Start the pump again and allow it to run until the trapped air is removed.

Low Pressure

Low pressure can be caused by a lot of different factors. If the nozzle is worn, replace it with a new one to fix the issue. If the belt slips, make sure to tighten it. Air leaks in the inlet plumbing may also cause low pressure. In this case, disassemble the pump and reseal it. The inlet suction strainer may also cause the problem. Clean it if it is clogged or check it if it is the proper size. Using the wrong size will definitely cause low-pressure issues. Inspect the pump for other leaks as well and repair them to see if it fixes the issue.

Noise and Pressure Thread Fluctuations

Clogs in the suction strainer or air leaks in the inlet fittings or suction hose can cause fluctuations in the pressure thread and noise. To repair the problem, clean the strainer or inspect the suction line for any loose liner or clogging debris.

Pump Runs Rough with Very Low Pressure

This may happen when the inlet of air is restricted. If so, check if the seal is airtight. If not, make sure to tighten the seal properly. Air leaks can also cause the problem as well as the stuck discharge valve and inlet. To fix the problem, make sure to inspect the valves and inlets for any clogging debris. Clean out any debris or replace the valves if they are worn out.

Manifold Water Leakage

If the manifold is leaking, replace it with a new one especially if it is already worn. Water leakage should be repaired as much as possible because it also causes low pressure.

Water in Crankcase

This can be caused by humid air that condenses into water. This can also occur when the packing is worn or the o-rings and piston rod sleeves are worn as well. This can be fixed by changing oil intervals and using high-grade non-detergent oil. Replace any worn parts as well.

Loud Noise

If the crankshaft pulley is loose or the bearing is worn, it causes loud noise on the pump. To fix the problem, tighten the setscrew or replace the bearing.