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1. Remove control valve from the backhoe.

2. Thoroughly clean the exterior of the valve before
beginning disassembly procedures.

3. At the BACK of the valve remove all bonnet assem-
bly parts which are connected to the spool. Keep
parts in the order of disassembly. See Figure 11 for
the parts involved in the make-up of the bonnet
assembly.

IMPORTANT: DO NOT remove the spool from the
valve. The seals can be replaced externally. Prevent
spools from turning or moving by inserting a screw dri-
ver through the clevis slot, or by running a rod through
the pin hole and using the rod as a handle. DO NOT
hold the spool with a wrench. This will destroy the fin-
ish.

4. At the BACK of the valve, remove seal retainer,
back-up washer, and spool O-ring seal, or retaining
sleeve,bonnet O-ring seal and spool U-cup seal.

5. Thoroughly clean counterbores.

6. Install new seals:

A. Spring-Centered Bonnet Assembly Only:

Lightly oil new O-ring seal. Slide O-ring seal over 

valve spool and insert in seal counterbore. Replace
back-up washer and seal retainer.

B. Float Bonnet Assembly Only:

Replace retaining sleeve on valve spool. Lightly oil
new U-cup seal. Slide U-cup seal over valve spool
being careful to orient seal as shown in Figure 11.
Install new O-ring seal in bonnet counterbore.

7. At the BACK of the valve replace bonnet assembly
parts, reversing the order in which they were disas-
sembled in step 3. Use 12 ft. lbs. torque to tighten
assembly screw on spring centered bonnet assembly.

8. At the FRONT of the valve remove all parts con-
nected to the spool (handle, linkage, etc.).

9. At the FRONT of the valve remove seal plate retain-
er, seal retainer, back-up washer and spool O-ring
seal.

10. Thoroughly clean counterbore.

11. Lightly oil new O-ring seal. Slide O-ring seal over
valve spool and insert in seal counterbore. Replace
back-up washer, seal retainer, and seal plate retainer.

12. Reattach all parts connected to the spool (handle,
linkage, etc.).

20

ASSEMBLY

Basic components for all models can be identified in Figure 12. Refer to Page 38 for photographs of units on their shipping pallets.  

General:

The backhoe has been partially disassembled and
strapped to a skid for shipping purposes. Initial installa-
tion on the tractor will require a hoist or other device
capable of safely lifting the entire backhoe from the skid.
After the initial installation is complete, the backhoe can
serve as its own erecting hoist, by lowering stabilizers
and bucket to the ground. Additional lifting devices will
not be required for normal removal and reattaching.

Assembly(865H & 965H) 

Figure 12

IMPORTANT: Tighten all hardware to torque require-
ments specified in torque chart.

1. Remove the stabilizer assemblies and any miscellaneous
items which have been fastened to the skid and arrange
conveniently. Reposition Stabilizer Cylinders from their ship-
ping configuration, by assembling them into the mainframe,
using the hardware provided. Be sure cylinder ports are
pointed upward and hoses are routed above the cylinder to
mainframe pivot pin connection. Refer to page 38.

Figure 12

CAUTION

DO NOT cut any strapping that
fastens the backhoe mainframe
and swing frame to the skid base
at this time.

CAUTION

Be sure hoist being used is suit-
able, has sufficient capacity and
is in the proper position.  Do not
allow anyone under a backhoe
member supported by hoist.

C

B

E

D

A

I

G

H

F

2. Support boom(A) and dipperstick (B) with hoist and
remove boom transport lock pin. Lower boom and
manually extend dipperstick until it rests on ground.
Move control handle to “BOOM DOWN” position as
required to aid movement.

Summary of Contents for 765H

Page 1: ...BUSH HOG Operator s Manual MODELS 665H 765H 865H 965H ASSEMBLY OPERATION MAINTENANCE BACKHOES 801 4 00 50034063...

Page 2: ...ler we stock genuine Bush Hog parts which are manufactured with the same precision and skill as our original equipment Our trained service personnel are well informed on methods required to service Bu...

Page 3: ...ush Hog dealer from whom he purchased it for service or replacement of defective parts which are covered by warranty Repairs to be sub mitted for warranty consideration must be made within forty five...

Page 4: ...Bush Hog duty taxes charges for normal service or adjustment loss of crops or any other loss of income rental of substitute equipment expenses due to loss damage detention or delay in the delivery of...

Page 5: ...he torque chart Machine operates properly Operators manual has been delivered to owner and he has been instructed on the safe and proper use of the backhoe Dealer s Signature CAUTION It is recommended...

Page 6: ...nd turn the tractor at low speeds 7 Stop tractor engine place transmission in park or neutral engage parking brake lower loader arms to ground cycle all hydraulic controls to relieve pressure allow ma...

Page 7: ...ck your local government regulations 4 BE SURE the SMV emblem is visible to the rear ADJUSTMENTS AND INSPECTION 1 CHECK pins that attach backhoe to tractor and all pivot pins for tightness several tim...

Page 8: ...his implement The following decals are located on the backhoe Keep decals clean and replace them immediately if they are missing Contact your dealer or Bush Hog for replacements Location Left Side of...

Page 9: ...not limited to instructions to Keep all guards in place when the machine is in operation Permit no riders on equipment Stop engine disconnect the power source and wait for all machine movement to stop...

Page 10: ...stabilizer control levers These controls are located on the control panel directly ahead of the operator See Figure 2 The following is a list of the controls with the function of each reading from lef...

Page 11: ...ver combined with the two operations performed by the bucket and dip perstick control lever provide four simultaneous oper Operating the Backhoe To avoid possible injury observe the following safety r...

Page 12: ...the hoe lessens it will begin to move It is balancing the force of one member against the other NOTE Actuating the bucket is the key to powerful dig ging Operating the crowd and bucket controls simul...

Page 13: ...rs and buck et back up to the full transport height It is normal for the backhoe to slowly settle while being transported Placing the Stabilizers Decreased Digging Depth Narrower Stabilizer Platform S...

Page 14: ...e crowding it out and swing ing it to the spoil pile As the pile is approached dump the bucket When the bucket is empty the dipperstick and bucket are in position to resume digging upon return to the...

Page 15: ...finishing straight walls or bellholes in sandy soil use a platform under the rear tires and the stabilizers The plat form distributes the load over a larger area and lessons the possibility of a cave...

Page 16: ...pped air must be removed after the hoses are connected Start tractor engine and operate backhoe through all movements fully several times to purge the system of air Hydraulic System Hoses Oil leaks in...

Page 17: ...increases wear greatly After greasing wipe off excessive grease from fittings Figure 6 Lubrication Points for Model 665H Figure 7 Lubrication Points for Model 765H Figure 8 Lubrication Points for Mod...

Page 18: ...e hydraulic system can now be disconnected CAUTION Make sure tractor PTO is disengaged and engine shut off before disconnecting pump or hydraulic lines a On PTO pump self contained systems the pump sh...

Page 19: ...t and crowd 8 9 10 11 12 13 23 25 26 E Loss of power in swing cylinders but other cylin ders functioning properly 8 9 10 11 12 13 23 24 26 F Maximum swing action cannot be obtained 12 15 G Slow operat...

Page 20: ...ow or defective relief pressure will have to be checked and corrections made Backhoe system pressure is 2100 psi for the 665H 2100 psi for the 765H 2400 psi for the 865H and 2250 psi for the 965H Reli...

Page 21: ...hat they can be reassembled in the same sequence 4 Mount the valve vertically in a vise to facilitate dis assembly and assembly 5 Remove the 3 tie rod nuts from the right end sec tion using a thin wal...

Page 22: ...ean counterbore 11 Lightly oil new O ring seal Slide O ring seal over valve spool and insert in seal counterbore Replace back up washer seal retainer and seal plate retainer 12 Reattach all parts conn...

Page 23: ...ackhoe member sup ported by hoist 3 Remove plastic bag containing bucket pins from backhoe Attach Bucket D to Dipperstick using one pin two bolts locknuts pin retainers and washers as needed to take u...

Page 24: ...4 x 4 1 2 bolt 9 flat washers 10 lock washer 9 and nut 11 Use hoist to raise or lower backhoe slightly until a hole in the upper bar aligns with a hole in the upper braces See Figure 13 6 Attach RH l...

Page 25: ...ion for further information Pump and reservoir kits are available as options The backhoe is mounted on the tractor lower link arms and an adjustable upper link is supplied to replace the tractor upper...

Page 26: ...own in Figure 15 Use four carriage 1 2 x 1 3 4 bolts 15 lockwashers 16 and nuts 17 5 Back tractor close to the backhoe Connect tractor lower link arms to lower link mounts at position C Figure 16 usin...

Page 27: ...actor hydraulic system as described in Hydraulic Hook Up section prior to remounting the backhoe onto the tractor 16 Attach bumper plate 37 to backhoe mainframe using two bolts 38 lockwashers and flat...

Page 28: ...cted to the pressure port of the trac tor s remote couplers or directly to the tractor valve The return hose B on the backhoe control valve should be connected directly to a port on the reser voir as...

Page 29: ...r hydraulic reservoir so that it bypasses all other tractor functions Backhoe Operation For the most part a backhoe will function about the same whether it is powered by an open center or closed cente...

Page 30: ...r link arms and an adjustable upper link is supplied to replace the tractor upper link A set of stabilizer arms are included They bolt from the adjustable upper link to the backhoe mainframe locking t...

Page 31: ...ces 221 using 3 4 x 5 bolts 203 flat washers 210 and nuts 207 Use hoist to raise or lower backhoe slightly until a hole in the upperr bar aligns with a hole in the upper braces See Figure 21 6 Attach...

Page 32: ...he 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 T...

Page 33: ...ation 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...

Page 34: ...erent valves IMPORTANT Never connect the return hose to a tractor remote coupler which can be pressurised Accidental pressurization can cause serious damage to backhoe valve Bush Hog Loader Valve Inle...

Page 35: ...e are positioned properly and are not pinched or damaged 2 665H and 765H Assemble 90 degree O ring adapter union 2 to power beyond sleeve 1 and direct fitting down through notch in Right Hand foot pad...

Page 36: ...E LOADER VALVE INLET OUTLET PRESSURE TO BACKHOE VALVE TRACTOR PRESSURE OUT PORT OUTLET INLET RETURN FROM BACKHOE VALVE TEE FITTING RETURN FROM LOADER VALVE TRACTOR RESERVOIR PORT Figure 24 662H 762H B...

Page 37: ...lock with two nuts 2 10 4 5 GPM PTO PUMP KIT Assemble suction hose 23 to pump 10 using reduc 35 er 14 90 degree beaded fitting 20 and hose clamp 24 as shown in Figure 25 6 1 or 8 GPM PTO PUMP KIT Ass...

Page 38: ...e 26 6 1 GPM PUMP KIT or 8 GPM PUMP KIT 14 20 15 1 27 9 2 24 10 25 13 7 4 9 2 23 5 21 24 FROM BACKHOE RETURN TO BACKHOE PRESSURE 6 12 3 16 19 18 22 11 17 FILTER ONLY 28 26 18 19 16 3 29 26 12 6 22 11...

Page 39: ...otation 180 180 180 180 G Loading Reach bucket at 60 3 2 3 7 3 7 4 11 H Transport Overhang 3 5 3 6 4 0 5 1 I Undercut 2 4 2 6 2 10 2 11 J Stabilizer Spread down position 6 6 7 5 8 3 9 3 K Stabilizer S...

Page 40: ...IZER CYLINDERS BEFORE REMOVING BACKHOE FROM SHIPPING PALLET Cylinder ports must be pointing upward and hoses routed above the cylinder to main frame pivot pin connection Models 865H Shown 965H Models...

Page 41: ...NOTICE INSTRUCTIONS FOR MOUNTING BUSH HOG BACKHOES ON SKID STEER LOADERS COME WITH THE INDIVIDUAL MOUNTING KITS THE EXAMPLE SHOWN BELOW IS A MODEL 865H MOUNTED ON A JOHN DEERE MACHINE 39...

Page 42: ...BUSH HOG L L C P O Box 1039 Selma AL 36702 1039 Telephone 334 874 2700 www bushhog com...

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