User manual

35
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 direct-
ed to another “open center” valve. This allows the
backhoe valve and a loader valve, or other accesso-
ry, to be connected to the tractor hydraulic system
simultaneously, 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 Bush
Hog. The first procedure shows the recommended
method of connecting a Bush Hog loader with a Bush
Hog valve to a Bush Hog backhoe. The second pro-
cedure shows the recommended method for con-
necting a Bush Hog backhoe and a competitive
loader or a non Bush Hog 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 Bush Hog 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 opera-
tor when seated in the operating position on the
backhoe.
FIRST PROCEDURE
ASSEMBLY OF A BUSH HOG BACKHOE
TO A BUSH HOG LOADER VALVE
IMPORTANT: Improper hydraulic hook-up can
cause serious damage to backhoe control valve or
other hydraulic components. Refer to the Bush
Hog loader Operator’s Manual during this proce-
dure.
When connecting the Bush Hog backhoe valve to a
Bush Hog 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
Bush Hog loader in past years. The fittings required
to convert the Bush Hog 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 Bush Hog 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 identification 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 O-rings on sleeve are posi-
tioned properly and are not pinched or damaged.
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 pressure 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
fitting directly to a port on the tractor reservoir as shown
in Figure 23.