How power steering specialists Fix Noisy Pumps
The whining or groaning of the power steering pump can be very annoying at first, but it often indicates a serious problem. Here we describe how we solve such faults.
What the Noise Is Telling You
A high-pitched whistle whilst turning the wheel could indicate that there is low power steering fluid or the fluid is aeration. A groan or screech which becomes louder when locked full left and right could be caused by the pump working harder than normal. This could be due to blockages around the reservoir fill area i.e. around the reservoir screen. A squeal upon starting up could indicate that the belt is loose or worn.
Checking Fluid and the Reservoir Screen
Fluid level is checked cold and rechecked warm. Fluid is checked for signs of water contamination or signs of air ingestion (it may appear milky or have a foamy appearance). The reservoir screen is removed and cleaned as required as a partially blocked screen can restrict the feed to the pump causing increased noise as the pump works harder to achieve the required pressure.
Pressure and Flow Testing
A pressure and flow test is the next diagnostic test carried out by power steering specialists. This test is usually carried out using a gauge that is attached to the high-pressure hose. This test will confirm whether or not the pump is producing the correct amount of pressure and flow to service the power steering system. It will also confirm if the pump is faulty and needs to be replaced, rather than just assuming that it is.
Repair or Replacement
Some pumps can be reconditioned with a new seal and bearings but this would generally be reserved for older vehicles or those of unusual make. A remanufactured exchange unit would generally be the more cost effective solution for modern vehicles, and would be supplied with a full warranty. Once the new pump has been fitted the power steering system would then need to be properly bled of all air.
Confirming the Fix
After repair of a power steering pump a road test with several turns lock to lock must be completed to confirm that the noise has been cured and that the repair has been held. Also the fluid level and condition must be re-checked.
