Mec Speed Level Series Service & Parts Manual page 159

Secton 9 - Troubleshootng - 3084ES Models
Problem
LIFT AND DRIVE
Main Relief Valve RV-3 out of
adjustment
No drive or lift
Pump or pump coupler failure
operation motor
operates
Diverter Valve EC-1 malfunction
Hydraulic tank empty
Motor malfunction
No drive or lift System interlock
operation motor
does not operate
Battery discharged
Problem
STEER
Joystick rocker switch inoperative
Steering Valve SV-2 inoperative
No steer in either
System interlock
direction
Hoses connected incorrectly
Pressure Relief Valve RV-2 set too
low
Steering Valve inoperative or stuck
Steers in one
No power to steering coil
direction only
System interlock
One or both steering cylinder
internal seal failure
Steers but not fully
or steers slowly Pressure relief valve set too low
King pin/s seizing in the bore
Wheels do not stay
One or both steering cylinder
in position while
internal seal failure
driving
Steering Valve SV-2 sticking or
damaged
Steers
uncommanded
Check Valve CV-1 or CV-2 damaged
or contaminated with debris
Page 152
Possible Cause
Possible Cause
Speed Level Seres - Servce & Parts Manual
Remedy/Solution
For test purposes, swap RV-3 with RV-2.
Inspect, replace as necessary
Inspect, replace as necessary
Check, fill with approved oil
Inspect, replace as necessary
Check HELP messages using EZ-Cal
Will receive 4-4 or 7-7 flash on GP400. Clean,
service and charge batteries. Battery charger may
not operate if battery voltage drops below 20 volts.
Remedy/Solution
Check rocker switch output on green and yellow
wires, input on blue wire.
Check steering valve for power or damage.
Check HELP messages using EZ-Cal
See hydraulic section for correct connection.
Set steer relief valve to 2000 PSI
Inspect; replace steering valve
Check for power and ground in both directions, repair
wiring
Check HELP messages using EZ-Cal
Check steering cylinder seals, replace
Set steer relief valve to 2000 PSI
Disassemble and inspect, repair, replace bushings
Check steering cylinder seals, replace
Remove and inspect for visible debris and stem
straightness, clean with solvent and air
Remove and clean or replace check valves see
hydraulic diagram for manifold location
January 2019