Esco 10439, Operating Instructions & Parts Manual

MAINTENANCE

Important: 

Use only a good grade 

hydraulic jack oil.  Avoid mixing different 
types of fluid and 

NEVER 

use brake fluid, 

turbine oil, transmission fluid, motor oil or 
glycerin.  Improper fluid can cause 
premature failure of the jack and the 
potential for sudden and immediate loss of 
load. 
 

Adding oil 

1 . 

With saddle fully lowered and jack 

in its upright, level position, remove oil filler 
plug.  It may be necessary to remove cover 
plate on same models. 
2. 

Fill until oil is level with the filler plug 

hole, reinstall oil filler plug and cover plate. 
 
Changing 

oil

For best performance and longest life, 
replace the complete fluid supply at least 
once per year. 
 

3. 

With saddle fully lowered, remove 

the oil filler plug.  It may be necessary to 
remove cover plate on some models. 
1. 

Lay the jack on its side and drain 

the fluid into suitable container. 

Note:

Dispose

of

hydraulic

fluid

 in 

accordance with local regulations. 

2.Fill with good quality jack oil.  We 
recommend Mobile ~DTE 13 or equivalent.  
Reinstall oil filler plug and cover plate.

Lubrication

1 . 

A coating of light lubricating oil to 

pivot points, axles and hinges will help to 
prevent rust and assure that wheels, 
casters and pump assemblies move freely. 
2. 

Periodically check the pump piston 

and ram for signs of rust or corrosion.  
Clean as needed and wipe with an oily 
cloth. 
 

 NEVER USE SANDPAPER OR ABRASIVE

MATERIAL ON THESE SURFACES!

TROUBLE SHOOTING

Symptom

Possible Cause Corrective

Action

Jack will not lift load        Release valve not tightly closed 

Overload condition 
Pressure of air supply is too low 

Ensure release valve tightly 
closed 
Remedy overload condition 
Change to a suitable pressured 
air source 

Jack bleeds off after 
lift 

Release valve not tightly closed 
Overload condition 
Hydraulic unit malfunction 

Ensure release valve tightly 
closed 
Remedy overload condition 
Contact ESCO Tech. Service 

Jack will not lower 
after unloading 

Reservoir overfilled 
Linkages binding 

Drain fluid to proper level 
Clean and lubricate moving parts 

Poor lift performance 

Fluid level low 
Air trapped in system 

Ensure proper fluid level 
With ram fully retracted, remove 
oil filler plug to let pressurized air 
escape, reinstall oil filler plug 

Will not lift to full 
extension 

Fluid level low 

Ensure proper fluid level