3406E Truck Engine Caterpillar

Jake Brake Compression Brake

Tightening Sequence for Noncurrent Mounting Bolts

A change to the tightening procedure for 340 Series compression brakes has produced two different sets of mounting bolts. The set of noncurrent mounting bolts can be identified by the exclusive use of 12 point bolts for mounting the compression brake to the cylinder head. Refer to Illustration 1. The set of current mounting bolts can be identified by containing 3 hex head bolts and one twelve point bolt. Refer to Illustration 3.

Illustration 1	g01096130
Typical top view of Jake Brake's compression brake

Use this procedure for tightening the compression brake to the engine.

1. Tighten two center bolts (1) and (2).

   Torque for center bolts ... 54 N·m (40 lb ft)

2. Tighten mounting stud nut (5).

   Torque for mounting stud nut ... 54 N·m (40 lb ft)

   Note: Some of the early 340, 340A, and 340B compression brakes utilized two mounting studs that are located in the front of the brake housing. If your application has two mounting studs, use a crisscross pattern to torque the mounting stud nuts and the center bolts.

3. Tighten two outer bolts (3) and (4).

   Torque for outer bolts ... 54 N·m (40 lb ft)

4. Tighten two center bolts (1) and (2) again.

   Torque for center bolts ... 109 N·m (80 lb ft)

5. Tighten the mounting stud nut (5) again.

   Torque for mounting stud nut ... 109 N·m (80 lb ft)

6. Tighten two outer bolts (3) and (4) again.

   Torque for outer bolts ... 109 N·m (80 lb ft)

Illustration 2	g01096145
Typical view of a Jake Brake's compression brake

(6) Final torque for slave piston adjustment screw locknut ... 34 N·m (25 lb ft)

(7) Final torque for solenoid valve ... 13 N·m (9 lb ft)

(8) Final torque for installation of the mounting stud into the cylinder head ... 65 ± 10 N·m (48 ± 7 lb ft)

Tightening Sequence for Current Mounting Bolts

A change to the tightening procedure for 340 Series compression brakes has produced two different sets of mounting bolts. The set of noncurrent mounting bolts can be identified by the exclusive use of 12 point bolts for mounting the compression brake to the cylinder head. Refer to Illustration 1. The set of current mounting bolts can be identified by containing 3 hex head bolts and one twelve point bolt. Refer to Illustration 3.

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Illustration 3	g01091089
The torque sequence and the bolt locations for installation of the Jake Brake compression brake.

1. Install hex head bolts (1), (3), and (4) into the positions that are shown in Illustration 3. Install the 12 point bolt (2) across from the mounting stud for the compression brake. Install the mounting stud nut (5) onto the mounting stud. Finger tighten the mounting bolts and the mounting stud nut.

   Note: Ensure that the placement of the bolts agree with the bolt locations that are shown in Illustration 3. Incorrect placement of the bolts will result in a loss of brake performance.

2. Refer to the torque sequence that is shown in Illustration 3. Tighten bolts (1), (2), (3), and (4) to the following preload torque.

   Preload torque for bolts ... 50 ± 7 N·m (37 ± 5 lb ft)

3. Tighten mounting stud nut (5) to the following preload torque.

   Preload torque for mounting stud nut ... 50 ± 7 N·m (37 ± 5 lb ft)

4. Use the torque sequence that is shown in Illustration 3. Tighten bolts (1), (2), (3), and (4) to the following torque-turn angle.

   Tighten the bolts for this additional torque-turn angle. ... 90 ± 5°

5. Tighten mounting stud nut (5) to the following torque-turn angle.

   Tighten the mounting stud nut for this additional torque-turn angle. ... 90 ± 5°

   Note: Some of the early 340, 340A, and 340B compression brakes utilized two mounting studs that are located in the front of the brake housing. If your application has two mounting studs, tighten the second mounting stud nut as the last nut in the torque sequence. Refer to Steps 3 and 5.

Illustration 4	g01087336
Typical view of a Jake Brake compression brake

(6) Final torque for solenoid valve ... 13 N·m (9 lb ft)

(7) Final torque for slave piston adjustment screw locknuts ... 34 N·m (25 lb ft)

(8) Final torque for installation of the mounting stud into the cylinder head ... 65 ± 10 N·m (48 ± 7 lb ft)

Slave Piston Lash Settings

Note: Refer to Testing and Adjusting, "Slave Piston Lash - Adjust" for the complete procedure for adjusting the slave piston lash.

Note: The slave piston lash settings are specific to the model number of the compression brake and to the serial number prefix of the engine. Use these settings only for the compression brakes and serial number prefixes that are specified in the table.

Pacbrake Compression Brake

Tightening Sequence for Pacbrake Compression Brakes

Illustration 5	g00975488
Typical top view of Pacbrake's engine compression brake

1. Tighten two center bolts (2).

   Torque for center bolts ... 54 N·m (40 lb ft)

2. Tighten mounting stud nut (4).

   Torque for mounting stud nut ... 54 N·m (40 lb ft)

3. Tighten two outer bolts (1).

   Torque for outer bolts ... 54 N·m (40 lb ft)

4. Tighten two center bolts (2) again.

   Torque for center bolts ... 109 N·m (80 lb ft)

5. Tighten the mounting stud nut (4) again.

   Torque for mounting stud nut ... 109 N·m (80 lb ft)

6. Tighten two outer bolts (1) again.

   Torque for outer bolts ... 109 N·m (80 lb ft)

(3) Final torque for slave piston adjustment screw locknut ... 34 N·m (25 lb ft)

Illustration 6	g00975493
Typical side view of Pacbrake's engine compression brake

(5) Final torque for installation of the mounting stud into the cylinder head ... 88 N·m (65.0 lb ft)

Slave Piston Lash Settings

Note: The slave piston lash settings are specific to the serial number of the engine. Use these settings only for the serial number that is specified in the table.

Note: Refer to Testing and Adjusting, "Slave Piston Lash - Adjust" for the complete procedure for adjusting the slave piston lash.