Manitowoc Grove RT530E-2 Service And Maintenance Manual page 174

BOOM
Symptom
3. Boom raises
slowly.
4. Boom lowers
slowly.
5. Boom will not raise.
4-26
Probable Cause
a. Low hydraulic oil level.
b. Low engine rpm.
c. Damaged relief valve.
d. Extremely cold hydraulic oil.
e. Improper hose or fittings, installed.
f. Operating two functions with in the
same control valve bank assembly.
g. Restriction in return hose.
h. Cylinder piston seals leaking.
i. Scored cylinder barrel.
j. Worn hydraulic pump section.
a. Low hydraulic oil level.
b. Low engine rpm.
c. Damaged relief valve.
d. Operating two functions within the
same control valve bank assembly.
e. Extremely cold hydraulic oil.
f. Improper hose or fittings installed.
g. Restriction in return hose.
h. Cylinder piston seals worn.
i. Scored cylinder barrel.
j. Worn hydraulic pump section.
k. Piston rod broken (loose from piston).
a. Low hydraulic oil.
b. Main relief valve or circuit relief valve
damaged.
c. Excessive load.
d. Worn or damaged hydraulic pump
section.
e. Broken pump shaft.
f. Broken pump drive coupling.
g. Broken control valve spool.
Published 4-22-15, Control # 556-00
RT530E-2 SERVICE MANUAL
Solution
a. Replenish hydraulic oil to proper level.
b. Increase and maintain engine rpm.
c. Repair or replace relief valve.
d. Operate unit to bring oil to operating
temperature.
e. Replace hose or fittings. (Refer to
Manitowoc Crane Care Parts Manual).
f. Feather controls to obtain desired
speed of both functions.
g. Replace return hose.
h. Replace all cylinder seals.
i. Hone or replace barrel.
j. Repair or replace pump section.
a. Replenish hydraulic oil to proper level.
b. Increase rpm to recommended level.
c. Repair or replace relief valve.
d. Feather controls to obtain desired
speed of both functions.
e. Operate unit to bring oil to operating
temperature.
f. Replace hose or fittings. (Refer to
Manitowoc Crane Care Parts Manual).
g. Replace return hose.
h. Replace all cylinder seals.
i. Hone or replace barrel.
j. Repair or replace pump section.
k. Replace piston rod and all cylinder
seals.
a. Replenish hydraulic oil to proper level.
b. Repair or replace relief valve.
c. Reduce load as required.
d. Repair or replace pump section.
e. Replace pump shaft and seals.
f. Replace drive coupling.
g. Replace control valve.