FG00053.
PARTS-SERVICE
July 20, 1995
B/C/W60-80XT
GRAM
W45XT, T5XT
SUBJECT: ACCEL POTENTIOMETER (HYSTER PART # 23111641 AND ACCEL SWITCH
(HYSTER PART # 2309240) TROUBLESHOOTING/SETUP AND INSTALLATION
PROCEDURES
FAULT PROCEDURES
The following are the common faults with the accelerator switch.
Fault #1: Lift truck will not move in either direction. The directional contactors close normally. No power
when the direction/speed control is moved.
Possible causes: Accelerator pot is damaged or needs to be adjusted.
Wires 18 and 29 are connected to the PMC controller improperly.
Fault #2: Directional contactors close, lift truck accelerates to full speed immediately.
Possible cause: Accelerator pot is damaged or needs to be adjusted.
Fault #3: Directional contactors close, lift truck accelerates to full speed but does not accelerate smoothly.
Possible cause: Accelerator pot is damaged
Fault #4: Directional contactors close, lift truck accelerates but not to full speed in one or both directions.
Possible cause: Accelerator pot needs to be adjusted
Direction/speed switch is worn or out of adjustment.
We reserve the right to make changes in design or add improvements without incur-
ring the obligation to make such changes in equipment previously manufactured.
H6030
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ACCELERATOR SWlTCH EVALUATION
Examine the accelerator switch for proper mechanical functions. Some accelerator switches do not have
sufficient lever gear and potentiometer gear engagement. This may be corrected by loosening the nut and
moving the potentiometer closer to the lever gear. Check to ensure that the gears are free to rotate through
full travel and return to neutral when the control lever is released.
ACCELERATOR POTENTIOMETER ADJUSTMENT
Refer to 2200 SRM 279, Page 24.
NOTES:
1. Potentiometer 2304385 was replaced by 2311164. This new potentiometer (identifiable by the white
and black wires and the white label denoting  DIODE PROTECTED ) is polarity sensitive. The white
wire, wire #29 is positive (+) side of the potentiometer.
2. To verify the proper connection of wires #18 and #29 to the PMC controller, refer to 2200 SRM 411,
Page 20, Figure 21 and 8000 SRM 457 for the appropriate wire schematic.
INSTALLATION OF THE ACCELERATOR POTENTIOMETER
The new potentiometer (part #2311164) has different mounting hardware that the prior potentiometer. The
flange bushing has been replaced with an O-ring and an additional star washer. The proper installation is
shown in Figure l.
1. POTENTlOMETER
2. STAR WASHERS
3. O-RING
4 NUT
5. MOUNTiNG PLATE
Figure 1
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If this does not remedy the gear engagement, then the slot in the mounting plate can be made deeper to
allow for more adjustment. See Figure 2.
Figure 2
Reinstall the potentiometer and check the gear engagement. The engagement should be consistent when the
control lever is rotated from neutral to full rotation.
If the gear engagement is significantly less at full rotation than in neutral, (the gear teeth lose mesh, see Figure
3) then the lever gear must be replaced.
CORRECT ENGAGEMENT INCORRECT ENGAGEMENT
Figure 3
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Early versions of the lever gear were made without the web. See Figure 4. These lever gears are more
likely to have engagement problems that those with the web.
WEB
LEVER GEAR
Figure 4
Also, check for wear between the lever gear and the actuating cam. See Figure 5.
WEAR POINT #1
WEAR POINT #2
Figure 5
Wear at point #1 will allow the lever gear to return further when the control lever is returned to neutral
causing the potentiometer to need adjustment. Wear at points #1 and #2 will prevent the actuating cam
from fully rotating the lever gear which, will not fully rotate the potentiometer, therefore the truck will not
achieve full speed. Replace worn parts.