1.Main relief valve control the pressure of open-close action.(The valve body is carved with words “主”).

2.The left and Right rotation is controlled separately.(The valve body is marked by arrows).

3.Except 6Ton excavator, other model excavator oil return to oil tank or radiator directly,please try not to return to excavator distribution valve so that to avoid valve explosion caused by high pressure in very short time of out-of-step oil return.