A: Severe attachment drift when controls are neutral, delayed joystick response, and a noticeable drop in pilot control pressure are definitive indicators. Internal debris holding the valve poppet open allows hydraulic oil to backflow freely, causing erratic attachment control.
A: Mechanics must absolute clean the surrounding block area prior to removal, replace all matching O-rings, and pre-lubricate the valve body with clean hydraulic oil. Tightening must be done using a calibrated torque wrench to the exact factory spec to avoid housing distortion.
A: Cross-reference your physical main control valve or pilot line diagram with parts manual specification sheets for EC350C, EC350D, or EC380D models. Confirming the thread pitch, port depth, and system serial number before dispatch guarantees total mechanical compatibility.
A: RITO utilizes ultra-smooth internal micro-finishing combined with specialized clearance tolerances between the valve spool and cage. This prevents localized heat seizing and enables the internal components to continuously shed micro-fine varnish deposits up to extreme temperatures.
A: We provide original, OEM, and high-quality aftermarket versions with stable supply capability.
Q:Why Choose RITO?
A:Listed Factory
Stable&Reliable Quality
OEM Factory for Chinese Top Excavator Brands
Supplier to Fortune 500 Companie





















