BR160, BR166, BR172, BR272 and BR378 Brush Cutters Caterpillar

Illustration 1	g01175426
(1) Hydraulic motor (2) Gearbox (3) Return line (4) Supply line (5) Frame (6) Blades

Disassembled View

Note: Remove the work tool from the host machine before you perform any disassembly procedure or any assembly procedure.

ReferenceRefer to the Operation and Maintenance Manual, "Work Tool Installation and Removal".

Illustration 2	g01292603

(1) Guard

(2) Gearbox ... 40 kg (90 lb)

Note: Use two people or a suitable lifting device for gearbox (2) .

(3) Coupler

(4) Hydraulic motor

(5) Setscrews for the coupler Apply 9S-3263 Thread Lock Compound to the threads.

(6) Frame

(7) These nuts require a special torque procedure. Refer to "Carrier (Design A)" or "Carrier (Design B)" for the correct torque specification.

(8) Carrier (blade)

(9) Blade

(10) Bolt (blade)

(11) Nut (carrier) ... 610 ± 80 N·m (450 ± 60 lb ft)

(12) Cotter pin

Carrier (Design A)

Special Torque Procedure

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Illustration 3	g01341210
Carrier (Design A)

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Illustration 4	g01149877

1. Remove the plate that covers the access hole on the top of the brush cutter.

2. Insert a socket through the access hole in order to remove each nut for each blade.

3. Remove blades from the brush cutter.

4. Clean new 264-9552 Pins, 271-2353 lockwashers, and 3D-4904 Locknuts with a cleaner/degreaser. Allow hardware to dry. Before assembly, verify that nothing is contaminating the bolts, lockwashers, locknuts, or hardware on the carrier assembly.

5. Apply 169-5464 Primer Loctite part #7649 to the bolt and nut threads per directions on label.

6. Apply either 154-9731 Thread Lock Loctite part # 271 (10 mil) or 155-0695 Thread Lock Loctite part # 271 (50 mil) in a circumferential band around the first 10 bolt threads in order to ensure full coverage of the mated threads after tightening.

   The Loctite should be stored in a sealed container in a dry location between 8 °C (46 °F) and 21 °C (70 °F). Do not use the product past the expiration date that is printed on the bottle.

7. Assemble the new blade, the bolt, the lockwasher and the nut to the carrier. Torque the nuts to 610 ± 80 N·m (450 ± 59 lb ft).

8. Confirm that blades rotate freely.

9. Attach a Special Instruction, SEHS7332, "Do Not Operate" warning tag or a similar warning tag to the Quick Disconnect of the Brush Cutter.

   The thread lock must be allowed to cure at temperatures of at least 4 °C (39 °F) for a minimum of 24 hours.

   Note: After the thread lock has cured, apply localized heat to the nut and the bolt in order to disassemble the nut and bolt. Heat the nut and bolt to approximately 250 °C (482 °F). Disassemble the nut while the nut is hot.

10. Install the plate that covers the access hole on the top of the brush cutter.

Carrier (Design B)

Special Torque Procedure

Illustration 5	g01341213
Carrier (Design B)

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Illustration 6	g01149877

1. Remove the plate that covers the access hole on the top of the brush cutter.

2. Insert a socket through the access hole in order to remove each nut for each blade.

3. Remove blades from the brush cutter.

4. Position the new blades on the brush cutter. Replace the nuts.

5. Torque the nuts to 1050 ± 80 N·m (775 ± 60 lb ft).

   There is an optional torque method for this design of carrier. Tighten the nut to an initial torque of 500 N·m (370 lb ft). Rotate the nut an additional (60 degrees) in order to achieve the required 1050 ± 80 N·m (775 ± 60 lb ft) torque value.

6. Install the plate that covers the access hole on the top of the brush cutter.