Hyundai r35z-7 Workshop Manual page 206

HOW TO CHECK INTERNAL BOOM CYLINDER LEAKAGE
1.
Lower the bucket teeth to the ground with
bucket cylinder fully retracted and arm
cylinder rod retracted almost in full.
2.
Disconnect hose(A) from rod side of boom
cylinder and drain oil from cylinders and
hose.(Put cups on piping and hose ends)
3. Raise bucket OFF the ground by retracting
the arm cylinder rod.
If oil leaks from piping side and boom
cylinder rod is retracted there is an internal
leak in the cylinder.
If no oil leaks from piping side and boom
cylinder rod is retracted, there is an internal
leak in the control valve.
5-23
R35Z75TS01
A
R5575BY02
R35Z75TS02