Remove, resurface, and reinstall the cylinder head on a 6.7L Cummins diesel engine, including valve train removal, gasket replacement, and torque-to-yield head bolt installation.

Warnings

Tools required

Parts

• Cylinder head gasket × 1 — Use OEM Mopar gasket
• Cylinder head bolt set (TTY) × 1 — Use OEM - torque-to-yield bolts
• Valve cover gasket × 1 — Use OEM specification
• Intake manifold gasket × 1 — Use OEM specification
• Exhaust manifold gasket × 1 — Use OEM specification
• Injector O-ring kit × 1 — Use OEM specification
• Anti-seize compound × 1 — Nickel-based high temperature
• Thread sealant × 1 — Use OEM specification

Fluids

• Mopar OAT Coolant (Purple) — 18 qt
• Mopar 5W-20 Synthetic Blend — 13 qt

Preparation

1. Park vehicle on level surface and engage parking brake
2. Disconnect both batteries (negative terminals first) and remove battery hold-downs
3. Drain cooling system completely using block drain and radiator petcock
4. Drain engine oil and remove oil filter
5. Remove engine cover and air intake system from turbocharger to air filter housing
6. Relieve fuel system pressure by loosening fuel filter bleed screw
7. Label and photograph all electrical connections, vacuum lines, and fuel lines for reassembly reference
8. Support engine weight with hoist or overhead support fixture before beginning disassembly

Procedure

1. 1

   Remove valve cover and upper engine components
   Disconnect engine wiring harness and position aside. Remove charge air cooler outlet tube. Disconnect fuel supply and return lines at fuel filter housing. Remove valve cover bolts in reverse of tightening sequence and carefully remove valve cover. Clean any residual gasket material from valve cover mating surface.
   Torque spec

   Cover Bolts22 Nm (16 lb-ft)
2. 2

   Remove rocker arms and pushrods
   Loosen rocker arm bolts gradually in a crisscross pattern to prevent bending pushrods. Remove rocker arm assembly and set aside. Remove all 12 pushrods and place in numbered holder or cardboard template to maintain original position. Inspect pushrod ends for wear or damage. Pushrods must be reinstalled in exact same positions.
   ⚠Number or mark each pushrod position 1-12 from front to rear. Mixing positions will cause valve train noise and accelerated wear.
   Torque spec

   Mounting Bolts37 Nm (27 lb-ft)
3. 3

   Disconnect fuel injectors and glow plugs
   Disconnect electrical connectors from all six fuel injectors. Remove high-pressure fuel lines from injectors using proper flare nut wrenches to prevent line damage. Cap all fuel line openings immediately. Remove glow plugs and electrical connections. Do not remove injectors from cylinder head at this time unless replacement is required.
   ⚠️Even with pressure relieved, residual fuel pressure exists. Use rags to contain fuel spray when breaking fuel line connections.
4. 4

   Remove intake and exhaust manifolds
   Remove intake manifold bolts in reverse sequence from outside to center. Carefully separate intake manifold from cylinder head, watching for coolant spillage. Remove exhaust manifold heat shield. Apply penetrating oil to exhaust manifold studs and allow to soak. Remove exhaust manifold nuts working from center outward (hot to cold). If studs break, mark for extraction during cylinder head service.
   ⚠Exhaust manifold studs are prone to breaking due to heat cycling. Work slowly and use heat if necessary.
   Torque spec

   Intake Manifold Bolts25 Nm (18 lb-ft)

   Exhaust Manifold Nuts30 Nm (22 lb-ft)
5. 5

   Disconnect coolant passages and external components
   Disconnect upper radiator hose and heater hoses from cylinder head. Remove coolant temperature sensors and save for reinstallation. Disconnect any remaining brackets, tubes, or wiring attached to cylinder head. Verify all connections are free before attempting head removal.
   Torque spec

   Sensor Bolts15 Nm (11 lb-ft)
6. 6

   Remove cylinder head bolts
   Remove cylinder head bolts in reverse of tightening sequence (work from outside toward center in three passes). Due to torque-to-yield design, bolts may require significant force to initially loosen. Once all bolts are removed, inspect for thread damage or necking. Discard all old head bolts - they cannot be reused. Clean bolt holes in block using thread chaser and compressed air.
   ⚠Head bolts must be loosened gradually in sequence to prevent head warpage. Do not remove any bolt completely until all have been loosened.
   Torque spec

   Cylinder Head Bolts65 Nm (48 lb-ft)
7. 7

   Remove cylinder head from engine block
   Break cylinder head seal using appropriate pry points at designated locations (typically at front and rear corners). Never pry between gasket surfaces. Attach lifting equipment to cylinder head using proper lift brackets. Carefully lift cylinder head straight up to clear dowel pins. Place cylinder head on clean padded work surface with combustion chambers facing up. Immediately cover open cylinders in block with clean rags to prevent debris entry.
   ⚠️Cylinder head weighs approximately 150-170 lbs. Use engine hoist or minimum of two people for safe removal.
8. 8

   Inspect and clean cylinder head and block surfaces
   Remove all gasket material from cylinder head and block surfaces using plastic scraper and wire brush. Do not gouge or scratch surfaces. Clean bolt holes in block thoroughly with thread chaser and blow out with compressed air. Inspect cylinder head surface for cracks, especially between valve seats and injector bores. Check head surface with precision straightedge and feeler gauge at multiple points. Maximum allowable warpage is 0.002 inches per 6 inches.
   ℹ️Record warpage measurements before resurfacing. Maximum material removal should not exceed 0.010 inches from original specification.
9. 9

   Send cylinder head for professional resurfacing
   Transport cylinder head to qualified machine shop for resurfacing. Provide specifications: surface finish 60-80 RA, maximum cut 0.010 inches. Request valve guide inspection, valve seat inspection, and pressure testing while head is at machine shop. Verify head height after resurfacing to ensure it remains within specification (affects compression ratio and valve geometry).
   ⚠Excessive resurfacing will advance valve timing and increase compression ratio. Stay within manufacturer limits.
10. 10

    Prepare for cylinder head installation
    Upon return from machine shop, clean cylinder head thoroughly with solvent and dry with compressed air. Verify all bolt holes in block are clean and dry - any oil or coolant will cause false torque readings. Install new dowel pins if worn. Apply light coat of engine oil to head bolt threads and underside of bolt heads. Do NOT apply sealant to head gasket - use gasket dry as supplied.
    ⚠Contamination in head bolt holes will prevent proper torque clamping. Ensure holes are completely clean and dry.
11. 11

    Install new head gasket and position cylinder head
    Position new head gasket on engine block, ensuring all alignment dowels engage properly and all coolant and oil passages align. Verify gasket orientation - 'TOP' or 'FRONT' markings must be correct. Install cylinder head alignment pins to guide head onto dowels. Using hoist or assistants, carefully lower cylinder head onto block, engaging alignment dowels. Remove alignment pins once head is seated.
    ⚠Head gasket is directional and must be installed correctly. Verify all passages align before lowering head.
12. 12

    Install and torque cylinder head bolts
    Install all new cylinder head bolts finger-tight. Following manufacturer tightening sequence (starting from center, working outward in spiral pattern): Step 1 - Torque all bolts to 48 lb-ft. Step 2 - Torque all bolts again to 48 lb-ft in sequence. Step 3 - Rotate each bolt an additional 90 degrees in sequence. Step 4 - Rotate each bolt another 90 degrees in sequence (total 180 degrees rotation after initial torque). Mark bolts with paint pen to track rotation.
    ⚠Torque-to-yield procedure must be followed exactly. Skipping steps or improper sequence will cause head gasket failure.
    Torque spec

    Cylinder Head Bolts65 Nm (48 lb-ft)
13. 13

    Reinstall pushrods and rocker arm assembly
    Apply assembly lubricant to pushrod ends. Install each pushrod in its original numbered position, ensuring it properly seats in lifter socket. Verify each pushrod rotates freely with light finger pressure. Position rocker arm assembly over pushrods, ensuring each rocker arm engages its respective pushrod and valve stem. Install rocker arm mounting bolts and torque in crisscross pattern to specification.
    ⚠Each pushrod must fully seat in lifter socket. Improper seating will cause valve train failure immediately upon startup.
    Torque spec

    Mounting Bolts37 Nm (27 lb-ft)
14. 14

    Reinstall manifolds and external components
    Install new exhaust manifold gasket. Apply anti-seize compound to exhaust manifold studs. Install exhaust manifold and torque nuts to 22 lb-ft working from center outward (hot to cold pattern). Install new intake manifold gasket and position intake manifold. Torque intake manifold bolts to 18 lb-ft in sequence from center outward. Reinstall glow plugs with anti-seize. Reconnect fuel injector lines and torque to specification. Install new injector O-rings if injectors were removed.
    Torque spec

    Exhaust Manifold Nuts30 Nm (22 lb-ft)

    Intake Manifold Bolts25 Nm (18 lb-ft)
15. 15

    Install valve cover and complete reassembly
    Install new valve cover gasket - ensure it seats properly in valve cover groove. Position valve cover on cylinder head, aligning all bolt holes. Install valve cover bolts and tighten in sequence from center outward to 7 lb-ft. Reconnect all electrical connectors, coolant hoses, and fuel lines. Reinstall charge air cooler tube, air intake system, and engine cover. Reconnect batteries (positive first, then negative).
    Torque spec

    Cover Bolts22 Nm (16 lb-ft)

Reassembly

1. Fill cooling system with 18 quarts of Mopar OAT Purple coolant, burping air from system using bleed screws
2. Fill engine with 13 quarts of Mopar 5W-20 synthetic blend oil and install new oil filter
3. Prime fuel system using lift pump or manual priming pump until firm pressure is felt
4. Double-check all electrical connections, fuel lines, and coolant hoses are secure
5. Verify no tools or rags remain in engine compartment

Verification

• With glow plugs removed, crank engine to verify oil pressure before full start
• Start engine and check immediately for oil leaks, fuel leaks, or coolant leaks
• Monitor for unusual valve train noise - ticking or tapping indicates pushrod misalignment
• Allow engine to reach operating temperature and verify cooling system operation
• Check for exhaust leaks at manifold gasket while engine is running
• Recheck valve cover and head gasket areas for leaks after engine reaches full temperature
• Perform test drive and monitor for proper engine performance, boost levels, and temperature stability
• Recheck valve cover bolt torque and head bolt area for leaks after 500 miles of operation

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