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.).

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.

Figure 12

C

B

A

E

I

DG

H

F

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.

CAUTION

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

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.

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.

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Bush Hog 865H, 965H, 665H, 765H manual Assembly