THIEMAN Series TVLR 125A, Руководство пользователя

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27.
g. Broken hydraulic line Broken or punctured hydraulic lines and fittings must be replaced with care
to avoid injury from high pressure oil streams.
h. Clogged or
disconnected suction
line
With the liftgate at the ground, disconnect the power unit and remove the
reservoir. Check to see if the suction tube is clogged or has fallen out of
the pump base. Clean the screen or reattach the suction tube as required.
i. Defective pump If all else fails, the power unit MAY be defective. If the liftgate is older,
the pump may be worn out and unable to pump fluid at pressure with the
correct flow rate. Feel free to contact Thieman for further consultation.
3. Problem Liftgate will not lower
Cause Correction
a. Defective or
improperly wired lower
switch
Check voltage on the black wire of the control cord near the switch. If no
voltage is present, the black wire from the motor start solenoid is loose or
broken and needs repaired. If voltage is present, then check for voltage at the
green wire on the switch with the switch in the “DOWN” position. If no voltage
is present, replace the switch.
b. Defective lowering
solenoid coil or valve
With the “DOWN” switch engaged, check for voltage on the green wire on
the lower solenoid valve coil terminal. If no voltage is present, the green
wire from the “DOWN” switch is loose or broken and needs replaced.
Check for proper ground at the purple wire on the lowering solenoid coil.
Repair or replace ground as required. If there is voltage (minimum of 9.5
volts) and proper ground at the lowering coil, and the valve is not opening
to allow the gate to lower, either the lower coil is bad or the entire lower
coil/valve assembly is bad. To check to see if the coil is defective, remove
the green and purple wires from the spade terminals on the lower coil and
check the resistance between these spade terminals (3.6 - 4.4 Ohm is
acceptable). Note: Low resistance can cause the 20-amp fuse to blow (see
Problem 1, part b) and high resistance will lower the coils magnetic force
and may not shift the valve. If proper resistance does not exist, replace the
defective coil, otherwise replace the defective lower coil/valve assembly.
c. Clogged or defective
hydraulic lines, fittings
or flow controls
Remove any obstruction in the hoses, fittings, and flow controls or replace
any hose, fitting or flow control which does not allow fluid to flow through
freely.
4. Problem Oil or foamy oil/air mixture flowing from reservoir breather
Cause Correction
a. Air is present in the
system
This can occur if air enters the system if the fluid level is low, see problem
2, part a, or if the suction tube is disconnected, see problem 2, part h.
Also, air may enter through fittings which are not tightened properly, so
check for any leaks around fittings or hoses. Once the source of the air is
determined, the cylinder must be bled of all air. Most air can be removed
from the system by lowering the gate to the ground to relieve all pressure
from the cylinder, unpinning the cylinder, and cycling them back and forth
several times from fully extended to fully retracted and allowing the pump
to bypass through the relief valves for a few seconds in each direction.
e. Reservoir was
overfilled or filled
with liftgate in wrong
position.
See the MONTHLY INSPECTION AND MAINTENANCE in the
“Maintenance Guide” section of this manual to find out what position the
liftgate should be in when checking the reservoir level and how full the
reservoir should be in that position.