28. MACHINES READY FOR ATTACHMENTS 28.2 HYDRAULIC CIRCUIT Change-over hydraulic circuit When the machine is equipped with an attachment or a bucket, set left and right 3-way valve a as follows. Referring to the following chart, turn the rotor of the right 3-way valve a using a wrench to select the attachment to be mounted. (The arrows indicating the port direction are stamped on the 3-way valve head). NOTICE When the machine is equipped with the breaker, connect the return circuit directly to the return filter. The set pressure of the relief valve is set to 20600 kPa (210 kg/ cm 2 , 2980 psi) as standard when delivered from the factory.
If a breaker by another manufacturer is installed, adjustment is required. Consult your Komatsu distributor. PC450-ENG 5-7 Attachment Right 3-way valve a Breaker etc. Right of machine Crusher etc. Right of machine When not used Right of machine