Section 5. Troubleshooting Model 8210/8250 Maintenance Manual
Symptom Tables: Lift/Lower System
5-20 Publication: 1146945/001, Revised: 25 Sep 2018
Unable to Pick Up a Load
Slow Lower
Load Drifting/Settling
Possible Cause Action
Load too large for the lift truck
capacity
Check the load weight. Check the lift pressure setting.
Battery problems Lead acid battery: Replace the battery with a fully-charged battery.
Lithium-ion battery: Check charge status LEDs for charge level.
Incorrect lift pressure adjustment Check and adjust the lift pressure setting.
Contaminated or bad pressure relief
valve
Check for contamination in the hydraulic fluid.
If contamination is present, flush, fill, and bleed the hydraulic
system. Clean the relief valve. fluid. See “Hydraulic Fluid” on
page 7-95.
If no contamination is found, replace the relief valve.
Bad lift pump or motor Replace the lift pump or motor.
Possible Cause Action
Bad lift/lower solenoid valve Repair or replace the solenoid valve.
Plugged or malfunctioning flow
control valve
Check for contamination in the hydraulic fluid.
If contamination is present, flush, fill, and bleed the hydraulic
system. Clean the relief valve. See “Hydraulic Fluid” on page 7-95.
If no contamination is found, replace the flow control valve.
Contamination in the lowering
solenoid valve
Inspect the solenoid for contamination or binding.
Mechanical binding in the lift
mechanism
Adjust or replace the mechanism.
NOTE: If the pump hits relief and lower is attempted, lowering is slow. Release the lower button
momentarily, then continue to lower. Normal lower speed should resume.
Possible Cause Action
Contaminated or bad check valve Check for contamination in the hydraulic fluid.
If contamination is present, flush, fill, and bleed the hydraulic
system. Clean the check valve. See “Hydraulic Fluid” on page 7-95.
If no contamination is found, replace the check valve.
Leaking or contaminated lowering
solenoid valve
Check for contamination in the hydraulic fluid.
If contamination is present, flush, fill, and bleed the hydraulic
system. Clean the solenoid valve. See “Hydraulic Fluid” on
page 7-95.
If no contamination is found, replace the solenoid valve.
Load too large for the lift truck
capacity
Check the load weight. Check the lift pressure setting.
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