Contenu
The condition described by most as "boiling" sometimes isnt. Though excess heat in the power steering system can indeed cause the fluid to boil, there are other conditions that can mimic the effect.
Pinched Lines
The pressure side line of a power-steering pump can sometimes become pinched. This causes pressure to back up into the reservoir and gives the appearance of boiling.
Low Fluid
A low-fluid condition may not allow the heat generated by the steering pump and rack to disperse, causing whats left to overheat and boil.
Power Steering Pump
A failing power steering pump will often generate excess heat through the grinding of worn bearings and gerotors. The fluid on the low-pressure side of the pump will begin to boil and rise through the reservoir.
Hard Driving
Rapid back-and-forth sawing on the steering wheel can cause an overheat condition in the rack-and-pinion steering.
Consequences
After it has been overheated, power steering fluid loses much of its lubricity and resistance to future super-heating.
