308C CR Excavator Hydraulic System – Cylinders (Boom, Stick and Bucket)



Illustration 1 g00756146

(1) Head end port

(2) Boom cylinder

(3) Cylinder

(4) Piston rod

(5) Snubber

(6) Piston

(7) Rod end port

(8) Stick cylinder

(9) Snubber

(10) Snubber

(11) Bucket cylinder



Illustration 2 g00422702

Snubber operation (extension of cylinder rod )

(9) Snubber

(12) Passage

As the boom control lever is moved to the boom RAISE position, or the stick control lever is moved to the stick IN position, the boom cylinder (2) and stick cylinder (8) extends close to the end of the extension stroke. Passage (12) is restricted by snubber (9). The movement of the piston rod slows down before the piston rod stops.




Illustration 3 g00422703

Snubber operation (retraction of cylinder rod )

(10) Snubber

(13) Passage

As the stick control lever is moved to the stick OUT position, stick cylinder (8) retracts close to the end of the retraction stroke. Passage (13) is restricted by snubber (10). The movement of the piston rod slows down before the piston rod stops. The shock load is absorbed when the piston is slowed down.