Loader Bobcat 773. Manual - part 27

CONTROL VALVE (S/N 509640660 & Above, S/N
509616542 & Above) (Cont’d)

Main Relief Valve

Assembly

Install new O–rings (Item 3) [A] and back–up ring (Item
2) [A] on the main relief valve.

Install the glid ring (Item 1) [A] & [B] over the O–ring.

Install the main relief valve (Item 1) [C].

Tighten to 35–40 ft.–lbs. (47–54 Nm) torque.

Load Check Valve

Assembly

Install a new O–ring (Item 1) [D] on the plug (Item 2) [D].

A

P–08971

B–06764

3

1

2

3

1

2

C

P–08969

1

D

P–11342

2

1

–2–54–

773 BICS Loader

Service Manual

B

P–08970

1

CONTROL VALVE (S/N 509640660 & Above, S/N
509616542 & Above) (Cont’d)

Load Check Valve (Cont’d)

Assembly (Cont’d)

Install the plug (Item 1) [A].

Tighten the plug (Item 1) [A] to 35–40 ft.–lbs. (47–54 Nm)
torque.

Install a new O–ring (Item 1) [B] on both of the load check
plugs.

Install the poppet (Item 2) [B], spring (Item 3) [B] and load
check plug (Item 4) [B] in the lift and tilt sections.

Tighten the plugs to 35–40 ft.–lbs. (47–54 Nm) torque.

Install the restrictor (Item 1) [C] in the lift section base end
port.

Install the end caps (Item 1) [D] on the base end of the lift
and tilt sections.

Install the BICS

™

 valve on the control valve. (See Page

2–27.)

NOTE: There are two restrictor sizes. 0.134 inch

(3,40 mm) and 0.141 inch (3,58 mm).

A

P–08967

1

C

P–08964

1

D

P–11013

1

1

773 BICS Loader

–2–55–

Service Manual

B

P–08966

4

1

3

2

CONTROL VALVE (S/N 509640660 & Above, S/N
509616542 & Above) (Cont’d)

Spool Seal Installation

To install new spool seals when the centering spring (tilt
spool) or the detent assembly (lift spool) are not removed
from the spool, use the following procedure:

Check the seal surface area in the control valve for rust,
corrosion, scratches, etc. Correct any irregularities
before continuing.

Oil and install the new spool seal (Item 1) [A] in the spool
bore.

Put plastic material (example: Plastic food wrap) on the
valve spool [B].

Put clean oil on the spool seal. Install the spool seal (Item
1) [B] on the spool. Be careful not to damage the seal on
the sharp edges.

NOTE: The seal must be installed with the lip face

toward the valve body. The lip face has the
largest outside diameter.

Remove the plastic material.

Install the spool into the control valve, by slowly turning
the spool while pushing the spool through the spool bore
and spool seal [C].

Be careful not to damage the spool seal.

Install the O–ring (Item 1) [D] and bushing (Item 2) [D].

Continue assembling the control valve.

A

P–08987

1

C

P–11012

D

P–08981

1

2

–2–56–

773 BICS Loader

Service Manual

B

CD–15080

1

CONTROL VALVE (S/N 509640659 & Below, S/N
509616541 & Below)

Removal And Installation

Stop the engine. Move the hydraulic controls to release
the hydraulic pressure. Raise the seat bar.

Raise the operator cab. (See Page 1–1.)

Control panel removal is optional. (See Page 3–1.)

When repairing hydrostatic and hydraulic
systems, clean the work area before
disassembly and keep all parts clean. Always
use caps and plugs on hoses, tubelines and
ports to keep dirt out. Dirt can quickly damage
the system.

I–2003–0888

Never work on a machine with the lift arms up
unless the lift arms are secured by an approved
lift arm support device. Failure to use an
approved lift arm support device can allow the
lift arms or attachment to fall and cause injury
or death.

W–2059–0598

Thoroughly clean the control valve area.

Loosen or remove the tubeline clamp (Item 1) [A].

Disconnect the drain hoses (Item 1) [B] from the main
control valve.

Disconnect the electric solenoid connectors (Item 2) [B].

Disconnect the outlet tubeline (Item 1) [C] from the
control valve.

Disconnect both tubelines (Item 1) [D] from the auxiliary
section of the control valve.

Revised Jan. 99

Raise the lift arms and install an approved lift arm support
device. (See Page 1–1.)

A

P–04105

1

C

P–04104

1

D

P–04100

1

773 BICS Loader

–2–57–

Service Manual

B

P–04099

1

1

2