Figure 211 High-pressure oil manifold (brake) 1. Brake Control Pressure (BCP)
sensor
2. Brake Shut-off Valve (BSV) assembly
3. M10 plug
4. Injection Control Pressure (ICP) sensor
5. M8 x 90 bolt (12) 6. M12 plug
7. Rail end plug assembly (2) 8. Injector oil inlet adaptor (6) 9. Back-up ring (6)
10. Injector oil inlet seal (6)
11. High-pressure oil manifold (brake)
12. Oil inlet O-ring
13. Brake actuator piston (6) 14. Oil pressure relief valve 15. Brake actuator piston lock nut
(6)
The engine brake system uses high-pressure oil in the high-pressure oil manifold, controlled by a brake shut-off valve, to force six brake actuator pistons down onto the valve bridges to partially open one exhaust
valve for each cylinder. The release of combustion chamber compression on the power stroke increases engine braking. See Diamond Logic® Brake System (page 50) for additional details.
Periodic Service
WARNING: To prevent personal injury or death, read all safety instructions in the "Safety Information" section of this manual.
WARNING: To prevent personal injury or death, shift transmission to park or neutral, set parking brake, and block wheels before doing diagnostic or service procedures.
WARNING: To prevent personal injury or death, wear safety glasses with side shields.
Limit compressed air pressure to 207 kPa (30 psi).
WARNING: To prevent personal injury or death, disconnect the main battery negative terminal before disconnecting or connecting electrical components.
WARNING: To prevent personal injury or death, do not let engine fluids stay on your skin.
Clean skin and nails using hand cleaner and wash with soap and water. Wash or discard clothing and rags contaminated with engine fluids.
GOVERNMENT REGULATION: Engine fluids (oil, fuel, and coolant) may be a threat
to the environment. Recycle or dispose
of engine fluids and filters according to
applicable regulations. Never put engine
fluids in the trash, on the ground, in sewers, or bodies of water.
NOTE: If the valve cover is removed for any reason, verify six brake piston locknuts are tight. If loose, verify and reset brake lash.
Engine Brake Lash Adjustment
Crankshaft is rotated twice during brake lash adjustment procedure.
• Three brake actuator pistons are adjusted when piston 1 is at Top Dead Center (TDC) compression.
• Three brake actuator pistons are adjusted when piston 6 is at Top Dead Center (TDC) compression.
Corresponding intake and exhaust valve lash can be adjusted (page 295) when piston 1 and 6 are at TDC compression.
NOTE: Valve lash adjustments are not required when adjusting engine brake lash.
1. Remove the valve cover (page 298) and EGR tube support bracket (page 124).
2. Turn the crankshaft in the direction of engine rotation to remove gear lash. Position piston 1 at TDC compression by observing cylinder 6 rocker arms in overlap as the vibration damper timing mark approaches the TDC mark on the front cover. Cylinder 6 exhaust valve will be closing (coming up) and the intake valve will be starting to open (going down).
3. If piston 1 is at TDC compression, see Chart 1 (page 189) and do steps 4, 5, and 6 for cylinders 1, 3, and 5.
Chart 1
Brake and valve lash adjustments (inches) with piston 1 at TDC compression (Chart 1) Cylinder 1 Cylinder 2 Cylinder 3 Cylinder 4 Cylinder 5 Cylinder 6 intake
0.019 0.019 0.019 0.019 0.019 0.019
Brake 0.019 Brake 0.019 Brake 0.019
Brake and valve lash adjustments with piston 1 at TDC compression
Chart 2
Brake and valve lash adjustments (inches) with piston 6 at TDC compression (Chart 2) Cylinder 1 Cylinder 2 Cylinder 3 Cylinder 4 Cylinder 5 Cylinder 6 intake
0.019 0.019 0.019 0.019 0.019 0.019
Brake 0.019 Brake 0.019 Brake 0.019
Brake and valve lash adjustments with piston 6 at TDC compression
Figure 212 High-pressure oil manifold (brake) 1. Cylinder 1
7. Brake actuator piston locknut (6) 8. Front of engine
Figure 213 Brake lash measurement 1. Brake actuator piston screw
2. Brake actuator piston locknut
3. Valve bridge 4. Feeler gauge
4. Measure brake lash when engine is cold. Put a 0.48 mm (0.019 in) feeler gauge (page 200) between the brake actuator piston and valve bridge, a light drag on the feeler gauge should be felt. If adjustment is required, loosen actuator piston locknut and turn actuator piston screw.
5. Once brake lash is set, tighten actuator piston locknut to special torque (page 200) and remove feeler gauge. Recheck lash with a light drag on feeler gauge. If drag is too tight or loose, repeat steps 4 and 5.
Corresponding valve lash can be adjusted before
6. Turn the crankshaft 360° in the direction of engine rotation to remove gear lash. Position piston 6 at TDC compression by observing cylinder 1 rocker arms in overlap as the vibration damper timing mark approaches the TDC mark on the front cover.
7. If piston 6 is at TDC compression, see Chart 2 (page 189) and do steps 4, 5, and 6 for cylinders 2, 4, and 6.
Removal
NOTE: If the valve cover is removed for any reason, verify six brake piston locknuts are tight. If loose, verify and reset brake lash (page 188).
Brake Shut-off Valve (BSV) Assembly 1. Remove valve cover (page 298).
Figure 214 BSV assembly
1. Solenoid 2. Solenoid nut 3. Harness connector
2. Disconnect UVC harness connector from BSV assembly.
3. Remove solenoid nut and solenoid from brake shut-off valve.
Figure 215 Brake shut-off valve
4. Remove brake shut-off valve from high-pressure oil manifold.
5. Remove and discard brake shut-off valve O-rings and back-up rings.
Brake Control Pressure (BCP) Sensor
Figure 216 BCP sensor
1. Disconnect 3-pin harness connector from BCP sensor, installed in the high-pressure oil manifold forward of cylinder 2 fuel injector.
2. Remove BCP sensor.
3. Discard sensor O-ring.
Under Valve Cover (UVC) Harness Valve Cover Gasket Assembly (Brake)
Figure 217 UVC harness assembly (brake)
1. Injector 1 connector (front of engine)
2. Injector 2 connector 3. Injector 3 connector 4. Injector 4 connector
5. Injector 5 connector 6. Injector 6 connector
7. Injection Control Pressure (ICP) sensor connector
8. Brake Shut-off Valve (BSV) connector
9. Brake Control Pressure (BCP) sensor connector
1. Disconnect four injector wiring harness (page 86) connectors from the UVC harness assembly.
NOTE: ICP and BCP sensors are identical and share the same part number.
2. Disconnect six injector connectors, ICP, and BCP sensor connectors.
3. Disconnect BSV connector.
4. Starting at one side, lightly pry up and open each of the six wire channel retainers while gently pulling up to remove UVC harness from engine.
High-pressure Oil Manifold (Brake)
1. Remove 12 M8 x 90 bolts holding high-pressure oil manifold to the cylinder head.
Figure 218 High-pressure oil manifold removal
WARNING: To prevent personal injury or death, get assistance to remove or install the high-pressure oil manifold assembly.
2. Lift high-pressure oil manifold straight up just enough to drain oil out of manifold before lifting it away from cylinder head.
3. Lift up and remove high-pressure oil manifold from engine.
Figure 219 Injector oil inlet adaptor installed in high-pressure oil manifold
1. Injector oil inlet adaptor 2. Backup ring
3. Injector oil inlet seal 4. Oil inlet tube
5. Internal O-ring (not serviceable)
4. Remove and discard injector oil inlet adaptor seals and backup rings.
5. Remove any damaged injector oil inlet adaptor assemblies using Injector Adaptor Removal Tool (page 200).
Figure 220 Oil inlet O-ring
6. Discard oil inlet O-ring
Oil Pressure Relief Valve
Figure 221 Oil pressure relief valve
1. Remove oil pressure relief valve from high-pressure oil manifold.
2. Discard valve O-ring.
Brake Actuator Piston Assembly
Figure 222 Brake actuator piston locknut
1. Remove brake actuator piston locknut.
Figure 223 Brake actuator piston removal
2. Remove brake actuator piston assembly from the high-pressure oil manifold.
Figure 224 Brake actuator piston assembly
3. Remove brake actuator piston.
NOTE: There are no seals associated with the brake actuator piston assembly.
Cleaning and Inspection
WARNING: To prevent personal injury or death, wear safety glasses with side shields.
Limit compressed air pressure to 207 kPa (30 psi).
1. Clean high-pressure oil manifold, brake actuator pistons, valve bridges, oil pressure relief valve, oil manifold plugs, brake shut-off valve, and brake control pressure sensor with a suitable non-caustic solvent.
2. Blow parts dry using filtered compressed air.
3. Inspect high-pressure oil manifold, oil pressure relief valve, and oil manifold plugs for cracks and leaks. Replace cracked or leaking parts.
Figure 225 Injector oil inlet adaptor installed in high-pressure oil manifold
4. Verify six injector oil inlet adaptor oil inlet tubes move and are not frozen. Inspect injector oil inlet adaptors for internal O-ring extrusion and high-pressure oil leak paths. Replace any adaptor which has an extruded internal O-ring, frozen oil inlet tube, or high-pressure oil leak path.
5. Inspect all brake actuator pistons and valve bridge contact surfaces. Look for pitting and material transfer deformation. Replace pitted or deformed parts if necessary. Polished surfaces are acceptable.
6. Inspect the brake shut-off valve and brake control pressure sensor for cracks and leaks. Replace cracked or leaking parts.
Installation
Brake Actuator Piston Assembly
Figure 226 Brake actuator piston assembly
1. Lubricate brake actuator piston and high-pressure oil manifold bore with clean engine oil.
2. Install brake actuator piston in high-pressure oil manifold. Install used brake actuator pistons in the same location as removed.
NOTE: There are no seals associated with the brake actuator piston assembly.
Figure 227 Brake actuator piston installation
Figure 228 Brake actuator piston locknut
4. Install brake actuator piston locknut.
5. Final brake lash adjustments will be made after high-pressure oil manifold is installed on the cylinder head.
Oil Pressure Relief Valve
Figure 229 Oil pressure relief valve
1. Install new O-ring on oil pressure relief valve.
2. Install oil pressure relief valve and tighten to special torque (page 200).