This procedure covers the removal and replacement of a single cylinder head gasket on the 3.5L EcoBoost V6 engine, including disassembly of timing components, head removal, surface preparation, and reassembly with new gasket and bolts.

Warnings

Tools required

Parts

• Cylinder head gasket × 1 — Use OEM Ford specification
• Cylinder head bolts (set) × 1 — Use OEM Ford specification - TTY bolts
• Valve cover gasket × 1 — Use OEM Ford specification
• Intake manifold gaskets × 1 — Use OEM Ford specification
• Exhaust manifold gaskets × 1 — Use OEM Ford specification
• Timing chain tensioner gasket × 1 — Use OEM Ford specification
• Coolant thermostat and O-ring × 1 — Use OEM Ford specification
• Engine oil filter × 1 — FL-910S or equivalent

Fluids

• Motorcraft Orange Coolant — 13 qt
• Motorcraft 5W-20 Synthetic Blend — 6 qt

Preparation

1. Disconnect negative battery cable and wait 10 minutes for airbag system to discharge
2. Raise vehicle and support securely on jack stands rated for vehicle weight
3. Remove engine under-shields and splash guards
4. Place large drain pan under radiator and drain cooling system completely
5. Drain engine oil and remove oil filter
6. Remove front wheel on side being serviced for better access
7. Install engine support bar across engine bay or attach engine hoist to support engine weight
8. Relieve fuel system pressure by removing fuel pump fuse and running engine until it stalls
9. Photograph or label all electrical connectors, vacuum lines, and hose routing before disconnection

Procedure

1. 1

   Remove intake and charge air systems
   Remove air intake tube and air filter housing. Disconnect charge air cooler (intercooler) tubes from throttle body and turbocharger outlet. Remove charge air cooler if necessary for access. Disconnect all vacuum lines, PCV hoses, and breather tubes connected to intake manifold and valve covers. Label each connection for reassembly.
   ⚠Charge air system operates under boost pressure. Ensure engine is off and cooled before disconnecting pressurized components.
2. 2

   Disconnect fuel system and electrical connections
   Disconnect fuel rail supply line using proper fuel line disconnect tool. Cap open fuel line to prevent contamination. Disconnect fuel injector electrical connectors (all six cylinders). Disconnect ignition coil connectors, then remove coils from cylinder head being serviced. Remove spark plugs. Disconnect camshaft position sensor, variable cam timing (VCT) solenoid, and any other sensors on the affected head.
   ⚠️Even with pressure relieved, residual fuel will be present in lines. Have rags ready to catch fuel and prevent spills on hot components.
3. 3

   Remove valve cover
   Disconnect any remaining wiring harness clips or brackets attached to valve cover. Remove valve cover bolts in reverse of tightening sequence (work from outside toward center). Carefully lift valve cover off and remove old gasket material. Inspect valve cover for warpage or damage.
4. 4

   Remove intake manifold
   Disconnect throttle body electrical connector and all remaining sensors on intake manifold. Remove intake manifold mounting bolts working from outside toward center. Carefully lift intake manifold away from engine and set aside. Remove and discard intake manifold gaskets. Stuff clean shop rags into intake ports to prevent debris entry.
   ⚠Intake manifold is heavy and awkward. Use caution when lifting to avoid dropping or damaging fuel rail components.
   Torque spec

   Intake Manifold Bolts25 Nm (18 lb-ft)
5. 5

   Remove exhaust manifold
   Disconnect oxygen sensor electrical connectors. Remove oxygen sensors from exhaust manifold if necessary for access. Spray exhaust manifold studs with penetrating oil and allow to soak. From underneath vehicle, disconnect exhaust pipe from manifold (may require cutting if studs are seized). Remove heat shields. Remove exhaust manifold nuts and carefully remove manifold. Remove and discard exhaust gaskets.
   ⚠Exhaust manifold studs are prone to breaking on high-mileage engines. Have replacement studs available and be prepared to extract broken studs from cylinder head.
   Torque spec

   Exhaust Manifold Nuts25 Nm (18 lb-ft)
6. 6

   Remove accessory drive components and front covers
   Remove serpentine belt. Remove belt tensioner and idler pulleys as needed for access. Remove crankshaft pulley bolt (requires crankshaft holding tool) and remove pulley. Remove engine front cover bolts and carefully pry cover away from engine block. Remove timing chain front cover to access timing components.
   ℹ️Crankshaft pulley bolt is very tight (typically 250+ lb-ft). Use proper holding tool and breaker bar.
7. 7

   Lock timing chain and remove camshaft components
   Rotate crankshaft to TDC position for cylinder #1 (verify timing marks align on crankshaft and camshafts). Install camshaft alignment tools per Ford special service tool instructions to lock camshafts in position. Mark timing chain to camshaft sprocket position with paint pen. Install timing chain holding tool to prevent chain from dropping. Remove camshaft VCT solenoids. Remove camshaft sprocket bolts while holding sprockets with chain wrench. Remove camshaft sprockets, leaving timing chain supported by holding tool.
   ⚠️If timing chain falls or jumps position, extensive engine damage will occur. Ensure chain is properly secured before removing sprockets.
8. 8

   Remove camshafts
   Remove camshaft bearing cap bolts in reverse order of tightening sequence (typically outside to inside, multiple passes). Carefully lift bearing caps off, keeping them in order for reinstallation. Remove camshafts from cylinder head and place on clean surface. Inspect camshaft lobes and journals for scoring or excessive wear. Keep all components organized by position.
   ⚠Camshaft caps must be reinstalled in exact original positions and orientations. Mark each cap location before removal.
9. 9

   Remove cylinder head
   Remove cylinder head bolts in reverse of tightening sequence (typically from center outward in multiple passes). Discard all cylinder head bolts as they cannot be reused. Carefully break cylinder head loose from block using plastic mallet or pry points (never pry between sealing surfaces). Lift cylinder head straight up and away from engine block. Place head on clean wooden blocks with combustion chambers facing up.
   ⚠Cylinder head weighs approximately 60 lbs. Use proper lifting technique or have assistant help to avoid injury or dropping head.
   Torque spec

   Cylinder Head Bolts - Step 140 Nm (30 lb-ft)
10. 10

    Clean and inspect sealing surfaces
    Remove old head gasket from engine block. Thoroughly clean cylinder head and engine block sealing surfaces using plastic gasket scraper and brake cleaner. Remove all old gasket material, carbon deposits, and oil residue. Do NOT allow debris to fall into cylinders, oil passages, or coolant passages. Use straightedge and feeler gauges to check cylinder head surface for warpage. Maximum allowable warpage is 0.002 inch across entire surface. If warpage exceeds specification, cylinder head must be machined or replaced. Inspect cylinder bores for scoring or damage. Check deck surface of block for warpage.
    ⚠Never use abrasive pads or metal scrapers on aluminum sealing surfaces. Scratches or gouges will prevent proper sealing and cause gasket failure.
    ℹ️Stuff clean rags into cylinders and oil return passages while cleaning to prevent debris entry.
11. 11

    Install new head gasket and position cylinder head
    Verify all cylinder head bolt holes in block are clean and dry. Install new cylinder head gasket on engine block, ensuring correct orientation (gasket has TOP marking and front/rear indicators). Align gasket dowel pins with holes in block. Verify gasket is fully seated. Carefully lower cylinder head onto block, aligning with dowel pins. Ensure head seats completely on gasket without shifting gasket position.
    ⚠Do not apply any sealant to head gasket unless specifically required by Ford service procedures. Modern multi-layer steel gaskets are designed to seal without additional sealant.
12. 12

    Install and torque cylinder head bolts
    Lightly oil threads and underside of bolt heads of NEW cylinder head bolts with clean engine oil. Install all cylinder head bolts finger-tight. Following the specified tightening sequence from center outward: Step 1 - Torque all bolts to 26 lb-ft. Step 2 - Torque all bolts to 44 lb-ft. Step 3 - Loosen all bolts 1 full turn (360 degrees). Step 4 - Torque all bolts to 26 lb-ft. Step 5 - Rotate all bolts an additional 90 degrees using angle gauge. Step 6 - Rotate all bolts an additional 90 degrees (total 180 degrees from Step 4). Verify all bolts have been torqued through complete sequence.
    ⚠️Cylinder head bolt torque sequence and procedure must be followed exactly. Deviation from specified sequence or torque values will result in head gasket failure and potential engine damage.
    ⚠Verify you are using NEW torque-to-yield head bolts. Old bolts will not achieve proper clamping force and will cause immediate gasket failure.
    Torque spec

    Cylinder Head Bolts - Step 140 Nm (30 lb-ft)
13. 13

    Reinstall camshafts and timing components
    Lubricate camshaft journals and lobes with clean engine oil. Install camshafts into cylinder head in correct positions (intake and exhaust are different). Install camshaft bearing caps in exact original positions and orientations. Torque camshaft cap bolts to specification in sequence from center outward in multiple passes. Install camshaft alignment tools to verify proper positioning. Install camshaft sprockets onto camshafts, aligning timing chain marks made during disassembly. Install and torque sprocket bolts while holding sprockets. Verify all timing marks align correctly before removing alignment tools. Remove chain holding tool and verify timing chain tension.
    ⚠️Verify timing alignment multiple times before proceeding. Incorrect timing will destroy engine when started.
14. 14

    Reinstall remaining components
    Install new exhaust manifold gaskets and reinstall exhaust manifold. Torque exhaust manifold nuts to specification in sequence from center outward. Reinstall oxygen sensors with anti-seize on threads. Install new intake manifold gaskets and reinstall intake manifold. Torque intake manifold bolts to specification from center outward. Install new valve cover gasket and reinstall valve cover. Torque valve cover bolts to specification from center outward. Reconnect all electrical connectors, vacuum lines, and hoses using photos/labels from disassembly. Install spark plugs and ignition coils. Reconnect fuel supply line. Reinstall timing covers, crankshaft pulley, and accessory drive components. Install new serpentine belt. Reinstall charge air cooler tubes and air intake system.
    Torque spec

    Exhaust Manifold Nuts25 Nm (18 lb-ft)

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

    Refill fluids and final preparation
    Install new engine oil filter. Refill engine with 6 quarts of Motorcraft 5W-20 synthetic blend oil. Close cooling system drains and refill with 13 quarts of Motorcraft Orange Coolant (mix per manufacturer specifications if using concentrate). Reinstall engine under-shields. Remove engine support equipment. Double-check all connections, bolts, and hoses are properly secured. Verify no tools or rags were left in engine bay. Reconnect battery negative cable.
    ℹ️Air will be trapped in cooling system. Plan to burp cooling system and verify proper coolant level after initial warm-up cycle.

Reassembly

1. Reassembly is covered in the main procedure steps as this is a complex repair requiring specific reassembly sequence
2. Ensure all electrical connectors are fully seated with locking tabs engaged
3. Verify serpentine belt is properly routed on all pulleys before starting engine
4. Check for any loose bolts or disconnected hoses before initial start

Verification

• Start engine and verify it runs smoothly without abnormal noises or misfires
• Monitor for any coolant, oil, or fuel leaks around repaired areas during initial warm-up
• Verify no exhaust leaks at manifold gasket
• Allow engine to reach operating temperature and verify cooling fans cycle normally
• Check coolant level after engine cools and top off as needed to account for air purging
• Monitor engine oil level and top off if necessary after settling period
• Test drive vehicle and verify normal operation, power delivery, and boost pressure
• Recheck all fluid levels after test drive and inspect for any new leaks
• Scan for diagnostic trouble codes to verify no timing, sensor, or fuel system issues

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