PAGE 2-13
CHAPTER 2 MAINTENANCE
NMC-WOLLARD
2021 Truax Blvd. Eau Claire, WI 54703 ● P: 715-835-3151● F: 715-835-6625 ● www.nmc-wollard.com
TML-704H Maintenance Lift Manual No. 310547
2 TROUBLE SHOOTING
SEPTEMBER 01, 2015
2.11 PROBABLE CAUSES/REMEDIES BY CODE:HYDRAULIC
Code
Number
Probable Cause
Test/Remedy
H1
Hydraulic hose or
tubing blocked or
pinched
Remove and inspect. Replace if necessary.
H2
Suction strainer
clogged
Remove and clean with mineral spirits. Check
condition of reservoir and reinstall strainer.
H3
Return filter clogged
Replace element. Check condition of reservoir and
suction strainer.
H4
Reservoir
contaminated
Open reservoir and check for contamination. Drain
and clean with mineral spirits and a lint-free cloth if
necessary. Flush system and refill with new oil.
(MOBIL-DTE-13)
H5
Oil level low
Add oil to proper level on sight gauge.
H6
Wrong type hydraulic
oil or contaminated oil
Flush system, drain and refill with new oil. See H4.
H7
Defective or
improperly adjusted
relief valve
Check pressures. Readjust or replace valve as
required.
H8
Counterbalance valve
out of adjustment
Remove and readjust as required, or replace.
H9
Valve clogged or
damaged
Remove and inspect. Clean or replace as
necessary.
H10
Cylinder rod seal
defective
Remove and inspect. Clean or replace as
required. Check rod surfaces for damage. Replace
if required.
H11
Cylinder piston seal
defective
Replace and test. Check cylinder bore for wear or
damage.
H12
Return spring broken
Remove and inspect. Replace spring or valve as
required.
H13
Pressure regulating
spring broken
Remove and inspect. Replace spring or valve as
required.
H14
Hydraulic pump
defective
Remove and test on a hydraulic test bench. Repair
or replace as necessary. (See Mfr’s service data,
Chap. 5.)
H15
Hydraulic pump shaft
seal leaking
Allow any air in reservoir to disperse. Run system.
Stop pump and crack the pump pressure line,
check for air in the oil. Remove and repair pump if
required.
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