Allmand Brothers TLB 535 - Manual (Page 37)

37
*Thermal Shock is defined on the following page.
PROBLEM POSSIBLE CAUSE CORRECTION
Leakage of cylinder piston seals or
accessory valve between cylinder
line or ports.
Replace seals or
accessory valve
SLIP—SLOW
MOVEMENT OF
STEERING WHEEL
FAILS TO CAUSE
ANY MOVEMENT OF
STEERED WHEELS
Worn steering control unit meter
Replace steering control
unit
TEMPORARY HARD
STEERING OR HANG-UP
*Thermal Shock
Check unit for proper
operation and cause of
thermal shock
ERRATIC STEERING
Air in system due to low level of oil,
cavitation of pump, leaky fitting,
pinched hose, etc.
Loose cylinder piston
*Thermal shock damage
Sticking flow control cartridge in gear
pump
Correct condition and add
fluid
Replace cylinder
Replace steering control
unit
Replace flow control
cartridge or gear pump
Air in hydraulic system. Most likely
air trapped in cylinders or lines
Bleed air out of system
“SPONGY” OR SOFT
STEERING
Low fluid level
Add fluid and check for
leaks
Steering column upper shaft is loose
or damaged Tighten steering wheel
nut
Lower splines of column may be
disengaged or broken
Repair or replace column
Steering control unit meter has a lack
of oil. This can happen on start-up,
after repair, or long periods of non-
use Usually starting engine
and allowing hydraulic oil
to circulate will cure the
problem
No flow to steering control unit—Can
be caused by:
Low fluid level
Add fluid and check for
leaks
Ruptured hose Replace hose
FREE WHEELING—
STEERING WHEEL TURNS
FREELY WITH NO FEELING
OF PRESSSURE AND NO
ACTION OF STEERED
WHEELS
Internal steering control unit damage
due to “Thermal Shock” Replace the steering
control unit
FREE WHEELING—
STEERING WHEEL TURNS
WITH SLIGHT RESISTANCE
BUT RESULTS IN LITTLE
OR NO STEERED WHEEL
ACTION
Cylinder piston seal blown out.
Determine the cause.
Correct the cause and
replace the blown seal.
EXCESSIVE FREE PLAY AT
STEERING WHEEL
Loose steering wheel nut. Steering
column shaft worn or damaged.
There should be very little play in the
unit itself
Repair or replace steering
wheel connection or
column
Broken or worn linkage between
cylinder and steered wheels
Check anchor points in
steering linkage between
cylinder and steered
wheels
EXCESSIVE FREE PLAY AT
STEERED WHEELS
Leaking cylinder seals Replace cylinder seals
STEERING (continued)