Power Train
Testing And Adjusting
7.
Restriction caused by components:
Correct and make adjustments to wheel brakes
and parking brakes that drag.
Make changes to tires with less restriction.
Check and correct wheel bearing torques.
Problem 5: Low resistance to ground [battery
polarity either positive (+) or negative (-) or a
medium voltage is in direct contact with truck
frame (body) or drive motor body].
Probable Cause:
1.
Dirty battery, electrolyte on top of cells and is in
contact with the frame. Current flows through
battery box, which places a voltage on the truck
frame:
Clean the battery with baking soda and water
solution.
2.
Battery or control panel wire connections in
contact with truck frame:
Make a continuity test and move the wire from
contact.
Remove wires in sequence until the fault is
cleared.
The fault will be in the wire last disconnected.
3.
Dirty motor:
Remove metallic or carbon dust with air
pressure.
4.
Wet motor:
To dry the motor, heat it to 90¡C (194¡F).
Problem: 6. Commutator surface has groove or
extra wear.
Probable Cause:
1.
Brushes are worn too low, brush wires caused
arcing on the commutator:
Replace the brushes. See Brush Inspection in
Testing And Adjusting and the method to make
the Brush Lift Estimate in Testing And Adjusting.
2.
Dirty motor; and possibly salt water got inside:
Disassemble motor, remove the debris with air
pressure. If necessary, dry the motor with heat
to 90¡C (194¡F)
3.
Grades of brushes mixed:
Make sure all the brushes are of DAEWOO
standards. Do not use other brands of brushes.
Problem 7: Lift truck moves faster in one
direction than the other direction with the same
amount of accelerator pedal movement in Bypass
mode (speed).
Probable Cause:
1.
Motor brushes not located in the correct electrical
position (brush neutral settings):
If the holes in the brush holder are not
extended, make them longer so that brush
holder can have a little rotation. When the
holder is in the correct position, lift truck speed
will be the same in both directions.
2.
One directional contactor worn more than the
other or loose connection on one contactor:
Check contactor for wear and tighten any loose
connections.
Problem 8: Lift truck will not get to top speed.
Probable Cause:
1.
Battery not fully charged or battery has bad cells:
Charge the battery. Check for bad cells.
Replace battery if necessary.
2.
A fault either in the drive motor, control panel or
drive train:
Check lift truck speed in both directions. If the
MicroController panel needs tuned up, make
adjustments as shown in the respective
MicroController System Operation module. If
the drive motor is at fault, make the tests of the
motor components in Testing And Adjusting.
Problem 9: Lift truck does not have enough
power to position itself under a load. Lift truck
does not have enough power on ramps or towing
trailers.
Probable Cause:
1.
Current limit (C/L) set too low:
Set current limit (C/L) to specification in the
MicroController System Operation module.
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