POWER BEYOND KITS
FOR TRACTORS WITH OPEN-CENTER HYDRAULIC SYSTEMS
General Description
A power beyond application is required to convert a hydraulic valve so that pressurized oil can be directed to another “open center” valve. This allows the back- hoe valve and a loader valve, or other accessory, to be connected to the tractor hydraulic system simulta- neously, without the inconvenience of using a flow diverting valve.
Since the power beyond application is only required on “open center” hydraulic systems, oil will be con- stantly flowing from the pump through the backhoe and loader or other accessory valve, and then back to the reservoir. “Open center” refers to this constant flow through the open center of the valves.
The assembly instructions cover two conditions that require a power beyond kit to be ordered from Great Bend. The first procedure shows the recommended method of connecting a Great Bend loader with a Great Bend valve to a Great Bend backhoe. The sec- ond procedure shows the recommended method for connecting a Great Bend backhoe and a competitive loader or a non Great Bend valve. The second is also used to operate the backhoe and loader off the back- hoe PTO pump kit option. In the first procedure, the power beyond plug is included with the loader valve when the valve is ordered. The second procedure requires the power beyond kit for the backhoe valve be ordered from Great Bend as a separate item.
The hoses and fittings required in either procedure to connect the two valves together are not supplied. The proper fittings and hose lengths required must be determined for each specific application. The parts must be supplied by the customer.
Tractor Preparation
Stop tractor, lower all attachments to the ground, and relieve pressure in all hydraulic lines by moving all control handles back and forth or side to side several times.
Note: The terms RIGHT and LEFT for all adapter parts are determined from the position of the operator when seated in the operating position on the backhoe.
FIRST PROCEDURE
ASSEMBLY OF A BUSH HOG BACKHOE TO A GREAT BEND LOADER VALVE
IMPORTANT: Improper hydraulic
When connecting the Great Bend backhoe valve to a Great Bend front end loader valve, the input pressure line from the tractor will be connected to the loader valve first. The power beyond pressure line will be connected to the input pressure port of the backhoe valve. In order to properly plumb the system, the loader valve will require converting to a power beyond valve. Refer to the Operator’s Manual received with the loader for the proper assembly of the power beyond valve.
There have been several different valves used on the Great Bend loader in past years. The fittings required to convert the Great Bend loader valve to a power beyond application are included in the loader valve kit. If the fittings (or plugs) cannot be located, they can be obtained from Great Bend Service Parts. Before attempting to order the plug you must first determine the manufacturer of the loader valve assembled to your loader. This can be determined from the identifi- cation plate located on the valve.
1.Install the power beyond plug received with the loader valve into valve cavity as shown in Figure 23 (Page 36). Make sure
2.Install a pressure line (supplied by customer) between the tractor pressure “out” port and the pres- sure inlet port of the loader valve.
3.Install a pressure line (supplied by customer) between the power beyond fitting of the loader valve and the pres- sure inlet port on the backhoe bulkhead connection as shown in Figure 23.
4.Complete assembly of “return” hoses as shown in Figure 23. Connect tee fitting to return outlet port on the backhoe bulkhead connector as shown. Connect return hose from rerturn outlet port of the loader valve to the branch port of the tee fitting. Hoses and tee supplied by customer. Connect a second return hose from the tee fit- ting directly to a port on the tractor reservoir as shown in Figure 23.
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