SLEEVE 9Z9437 - Caterpillar

Illustration 1 g00434058
Location of the cylinder crossover relief valve
Illustration 2 g00298579
(1) Valve (2) Valve (A) Port (B) PortThe relief valve is used to prevent damage from high pressure oil in the cylinder circuit. This occurs when the steering wheel is stationary and an outside force on a front wheel suddenly moves a cylinder rod into a cylinder or out of a cylinder.While the steering wheel is stationary a sudden movement of the front wheels due to striking an object will cause an increase in the oil pressure in one end of each cylinder. This increase in oil pressure is also felt through port (A) or port (B) by valve (1) or valve (2). At an oil pressure of approximately 18270 kPa (2650 psi), valve (1) or valve (2) will open. This will allow oil flow to the low pressure side of the cylinders.