The IHMEE hydraulic system operates at oil pressures up to 3,000 psi (20 680 kPa). Never
disconnect any hydraulic line or fitting without first dropping system pressure to zero. Failure to
comply may result in serious injury or death to personnel.
Hydraulic fluid (Dexron III) is TOXIC. Wear protective goggles and gloves; use only in
well-ventilated area; avoid contact with skin, eyes, and clothes. Skin and clothing that come in
contact with hydraulic oil should be washed immediately. Saturated clothing should be removed
immediately. Failure to comply may result in injury to personnel.
Ensure that only the indicated auxiliary valve is operated. You are within the backhoe crush zone
when operating the backhoe auxiliary valve. Manual operation of any other valves can cause
serious injury or death.
(11) Locate backhoe hydraulic valve block (1) under backhoe top plate.
(12) Use hydraulic valve manual override lever (2) to operate auxiliary valve (3) until all hydraulic pressure is
(13) Using a clean rag, clean area around quick disconnect coupling dust caps on dipper and attachment hoses and
remove dust caps.
(14) Using a clean rag, clean quick disconnect couplings.
(15) Connect attachment hydraulic lines to backhoe quick disconnect couplings.
The operation of the attachments is controlled by the joysticks on the operators seat. Refer to the attachment's OEM
manuals for details of their safe operation.
It is important to maintain the correct hydraulic fluid flow when using the attachments. If the flow is
too low, the efficiency of operation will be impaired. If it is too high, damage to the attachment may
The flow is controlled by adjusting the engine speed. Table 8-1 shows the correct engine speed for some common
hydraulic attachments. A decal showing this information is attached to the side console in the cabin of the vehicle.