6
Maintenance
1. Lubricate each friction point monthly with #2
tube grease.
2. Check the movement and wear of wheels.
3. Check for oil leakage from the hydraulic
cylinder.
4. Store with table in lowered position.
Troubleshooting DSLT-770 Double Scissor Lift
Items in parentheses refer to the index numbers in the parts breakdown.
Trouble Probable
Cause
Remedy
Table will not lift.
Oil level low in hydraulic pump.
Remove air breather (9) and fill with
hydraulic fluid.
Lowering valve (29) or steel ball (26) is
not seating.
Clean lowering valve (29) or steel ball
(26) or replace.
Relief valve is not adjusted properly.
Reload truck within load capacity and
adjust valve by pressure relief adjusting
screw (17).
Table will not remain
elevated.
Lowering valve (29) or steel ball (26)
not seating properly.
Clean or replace lowering valve (29) or
steel ball (26).
O-ring (5) or U-packing (7) is worn out.
Replace o-ring (5) or U-packing (7).
Table will not lower.
U-packing (7) is worn out.
Replace U-packing (7).
Lowering valve relief plug (16) is
clogged.
Replace lowering valve relief plug (16).
Oil leaks from lowering
valve.
O-ring (28) is worn out.
Replace o-ring (28).
Oil leaks from pump
cylinder.
Oil seal (39) or U-packing (40) worn out. Replace oil seal (39) or U-packing (40).
Replacement Parts
Replacement parts are listed on the following pages. To order parts or reach our service department, call 1-
800-274-6848 Monday through Friday, 8:00 a.m. to 5:00 p.m. CST. Having the Model Number and Serial
Number of your machine available when you call will allow us to serve you quickly and accurately.
Non-proprietary parts, such as fasteners, can be found at local hardware stores, or may be ordered from JET.
Some parts are shown for reference only, and may not be available individually.
