Head Gaskets - Both

Complete replacement of both cylinder head gaskets on the 3.0L V6 Twin Turbo engine, including timing chain removal, cylinder head removal, surface preparation, and reassembly with proper torque sequences.

Warnings

Tools required

Parts

• Cylinder head gasket - left bank × 1 — Use OEM specification
• Cylinder head gasket - right bank × 1 — Use OEM specification
• Valve cover gasket - left × 1 — Use OEM specification
• Valve cover gasket - right × 1 — Use OEM specification
• Timing cover gasket × 1 — Use OEM specification
• Cylinder head bolt set (both banks) × 1 — Use OEM specification - typically TTY
• Exhaust manifold gaskets × 2 — Use OEM specification
• Intake manifold gaskets × 1 — Use OEM specification
• Oil drain plug crush washer × 1 — Use OEM specification
• Coolant temperature sensor O-ring × 2 — Use OEM specification
• Various O-rings and seals kit × 1 — Use OEM specification
• Engine oil × 6 — Selenia Racing 10W-60
• Oil filter × 1 — Use OEM specification

Fluids

• Selenia Racing 10W-60 — 5.5 qt
• Maserati OAT Coolant — 10 qt

Preparation

1. Park vehicle on level surface and engage parking brake
2. Disconnect negative battery cable and wait 10 minutes for system capacitors to discharge
3. Remove engine cover and undertray panels
4. Drain engine coolant completely into appropriate container
5. Drain engine oil and remove oil filter
6. Relieve fuel system pressure by removing fuel pump fuse and cranking engine until it stalls
7. Remove front strut tower brace if equipped
8. Tag and photograph all electrical connectors, vacuum lines, and coolant hoses for reassembly reference
9. Support engine with hoist or support fixture from above

Procedure

1. 1

   Remove intake and accessory components
   Remove air intake system including air filter housing and intake ducting. Disconnect throttle body electrical connector and remove throttle body. Disconnect fuel lines using proper disconnect tools. Remove intake manifold by disconnecting all vacuum lines, electrical connectors, and breather hoses. Remove mounting bolts in reverse of tightening sequence and lift intake manifold away. Remove ignition coils and spark plugs from both cylinder banks.
   Torque spec

   Intake Manifold Bolts26 Nm (19 lb-ft)
2. 2

   Remove valve covers and accessory drive
   Disconnect all electrical connectors from valve covers including VVT solenoids and camshaft position sensors. Remove PCV system components and breather hoses. Unbolt and remove both valve covers. Remove serpentine belt by releasing tensioner. Remove crankshaft pulley bolt using impact wrench or holding tool, then remove pulley. Remove power steering pump and AC compressor (if equipped) and secure aside without disconnecting refrigerant lines.
   ⚠Crankshaft pulley bolt requires significant torque to remove. Use impact wrench or proper holding tool to prevent crankshaft rotation.
   Torque spec

   Cover Bolts18 Nm (13 lb-ft)

   VVT Solenoid Bolt10 Nm (7 lb-ft)

   Crankshaft Pulley Bolt180 Nm (133 lb-ft)
3. 3

   Remove timing cover and set engine to TDC
   Remove all timing cover bolts in sequence, noting different bolt lengths and locations. Carefully remove timing cover and gasket. Rotate crankshaft clockwise to Top Dead Center (TDC) for cylinder #1 using crankshaft socket. Verify timing marks on camshaft sprockets align with marks on cylinder heads and crankshaft keyway is at 12 o'clock position. Mark timing chain position relative to sprockets with paint marker for additional reference.
   ⚠Document timing chain position thoroughly with photos. This is critical for proper reassembly timing.
   Torque spec

   Cover Bolts18 Nm (13 lb-ft)
4. 4

   Remove timing chain and camshaft components
   Install timing chain tensioner pins or clips to lock tensioners in compressed position. Remove timing chain tensioner bolts and remove tensioners. Unbolt timing chain guides. Hold camshafts using wrench on hex section and remove camshaft sprocket bolts from all four camshafts (intake and exhaust, both banks). Remove camshaft sprockets and timing chain as an assembly. Remove camshaft caps in reverse of tightening sequence (outside to center), noting cap positions and orientation. Carefully remove camshafts and store in protected area.
   ⚠Camshaft caps are position-specific and must be reinstalled in exact original locations. Label each cap clearly.
   Torque spec

   Timing Chain Tensioner Bolt25 Nm (18 lb-ft)

   Camshaft Sprocket Bolt80 Nm (59 lb-ft)

   Camshaft Cap Bolts14 Nm (10 lb-ft)
5. 5

   Remove exhaust manifolds
   Disconnect oxygen sensor electrical connectors from both banks. Remove heat shields from exhaust manifolds. Disconnect exhaust pipes from manifolds at flange connections. Remove exhaust manifold nuts in crisscross pattern and remove both exhaust manifolds. Inspect manifolds for warping or cracks.
   Torque spec

   Exhaust Manifold Nuts36 Nm (26 lb-ft)
6. 6

   Remove cylinder heads
   Disconnect all remaining electrical connectors from cylinder heads including coolant temperature sensors. Disconnect coolant hoses from cylinder heads. Loosen cylinder head bolts in reverse of tightening sequence (outside to inside pattern) in multiple passes. Remove cylinder head bolts completely - these are torque-to-yield and must be discarded. Carefully lift cylinder heads off engine block using proper lifting points. Place heads on padded surface with gasket surface facing up.
   ⚠Cylinder heads are heavy (approximately 40-50 lbs each). Use proper lifting technique or assistance to avoid injury.
   Torque spec

   Cylinder Head Bolts93 Nm (68 lb-ft)
7. 7

   Inspect and clean all mating surfaces
   Thoroughly inspect cylinder head gasket surfaces and engine block deck for damage, warping, or excessive corrosion. Use straight edge and feeler gauge to check flatness - maximum allowable warpage is typically 0.002 inches per 6 inches. Clean all gasket surfaces using plastic scrapers first, then metal scrapers carefully to avoid gouging aluminum. Remove all old gasket material, sealant, and carbon deposits. Clean surfaces with brake cleaner and compressed air. Stuff clean rags into cylinders to prevent debris entry. Inspect cylinder head bolt holes in block for thread damage and clean thoroughly.
   ⚠Any scratches or gouges in gasket surfaces can cause leak paths. Surface must be perfectly clean and smooth.
   Torque spec

   Gasket Surface Bolts22 Nm (16 lb-ft)
8. 8

   Install new head gaskets and cylinder heads
   Remove rags from cylinders. Verify all dowel pins are present and properly seated in engine block. Install new cylinder head gaskets onto engine block, ensuring correct orientation (gaskets are bank-specific and have TOP markings). Verify gasket coolant and oil passage holes align perfectly with block passages. Carefully lower cylinder heads onto block, aligning with dowel pins. Install NEW cylinder head bolts finger tight. Tighten cylinder head bolts in proper sequence (center outward pattern) in multiple steps: First pass to 30 Nm, second pass to 60 Nm, third pass to final torque of 93 Nm, then apply additional angle torque as specified (typically 90 degrees additional rotation).
   ⚠️Cylinder head bolts MUST be new torque-to-yield bolts. Old bolts will stretch beyond elastic limit and cause gasket failure.
   Torque spec

   Cylinder Head Bolts93 Nm (68 lb-ft)
9. 9

   Install exhaust manifolds
   Install new exhaust manifold gaskets onto cylinder heads. Position exhaust manifolds and install new manifold nuts finger tight. Tighten exhaust manifold nuts to specification in crisscross pattern starting from center fasteners working outward. Install heat shields. Reconnect exhaust pipes to manifolds with new gaskets. Connect oxygen sensor electrical connectors.
   Torque spec

   Exhaust Manifold Nuts36 Nm (26 lb-ft)
10. 10

    Install camshafts and timing components
    Lubricate camshaft journals and lobes with assembly lube or engine oil. Install camshafts into cylinder heads in correct positions (intake/exhaust marked). Install camshaft caps in original locations with markings visible and arrows pointing toward front of engine. Tighten camshaft cap bolts in sequence from center caps outward in multiple passes to final torque of 14 Nm. Verify camshafts rotate freely. Position crankshaft at TDC for cylinder #1. Install timing chain onto camshaft sprockets according to timing marks documented during disassembly. Install sprockets onto camshafts, aligning timing marks precisely. Hold camshafts with wrench on hex and tighten sprocket bolts to 80 Nm. Install timing chain guides and tensioners with pins/clips still installed. Remove tensioner pins to activate tensioners. Rotate engine two complete revolutions by hand and verify all timing marks realign perfectly.
    ⚠️Verify timing marks alignment at least three times before proceeding. Incorrect timing will destroy engine on startup.
    Torque spec

    Camshaft Cap Bolts14 Nm (10 lb-ft)

    Camshaft Sprocket Bolt80 Nm (59 lb-ft)

    Timing Chain Tensioner Bolt25 Nm (18 lb-ft)
11. 11

    Install timing cover and front accessories
    Clean timing cover mating surface thoroughly. Install new timing cover gasket or apply RTV sealant as specified. Position timing cover and install bolts in proper sequence, tightening 8mm bolts to 25 Nm. Install crankshaft pulley and tighten bolt to 180 Nm. Install power steering pump, AC compressor, and serpentine belt tensioner. Install serpentine belt according to routing diagram.
    Torque spec

    Cover Bolts18 Nm (13 lb-ft)

    Crankshaft Pulley Bolt180 Nm (133 lb-ft)

    Mounting Bolts50 Nm (37 lb-ft)
12. 12

    Install valve covers and intake system
    Install new valve cover gaskets onto valve covers. Position valve covers onto cylinder heads and install bolts in sequence from center outward to 10 Nm. Reconnect VVT solenoids, camshaft position sensors, and PCV system components. Install new intake manifold gaskets. Position intake manifold and tighten bolts in proper sequence to 26 Nm. Reconnect all vacuum lines, fuel lines, and electrical connectors. Install throttle body with new gasket. Install spark plugs to proper specification. Install ignition coils. Install air intake system including filter housing and ducting.
    Torque spec

    Cover Bolts18 Nm (13 lb-ft)

    VVT Solenoid Bolt10 Nm (7 lb-ft)

    Intake Manifold Bolts26 Nm (19 lb-ft)
13. 13

    Refill fluids and prepare for startup
    Install new oil filter. Install oil drain plug with new crush washer and torque to 35 Nm. Fill engine with 5.5 quarts of Selenia Racing 10W-60 oil. Fill cooling system with Maserati OAT coolant using vacuum fill method if available, or fill slowly through expansion tank allowing air to bleed. Reconnect negative battery cable. Verify all electrical connectors are secured. Double-check that all tools and rags have been removed from engine bay.
    ℹ️Use vacuum cooling system fill tool to eliminate air pockets in cooling system if available.
    Torque spec

    Oil Drain Plug35 Nm (26 lb-ft)
14. 14

    Initial startup and break-in
    Turn ignition to ON position without starting to prime fuel system. Check for fuel leaks. Crank engine for 5-10 seconds without starting to build oil pressure. Start engine and immediately check for oil pressure indication. Allow engine to idle and monitor for any unusual noises, leaks, or smoke. Check for coolant, oil, and fuel leaks at all connection points. Bleed cooling system by running engine to operating temperature with heater on full. Add coolant as necessary. After initial warm-up, shut down engine and allow to cool. Recheck all fluid levels and top off as needed. Reinstall engine covers and undertray.
    ⚠Monitor engine closely during first startup. Shut down immediately if unusual noises, excessive smoke, or rapid fluid loss occurs.

Reassembly

1. All fasteners must be torqued to specification in proper sequence - do not skip steps or guess at torque values
2. Use only new cylinder head bolts, gaskets, and single-use fasteners - never reuse TTY bolts
3. Apply assembly lube to all camshaft and rocker arm contact surfaces during installation
4. Verify timing chain alignment multiple times before final assembly - this is the most critical aspect of this repair
5. Install all electrical connectors fully until they click - verify lock tabs are engaged
6. Route all wiring harnesses and hoses in original positions away from hot or moving components

Verification

• Start engine and verify smooth idle with no unusual noises, misfires, or rough running
• Check for coolant, oil, and fuel leaks at all disturbed connections while engine is running and after shutdown
• Verify engine reaches normal operating temperature and cooling fans cycle properly
• Scan for diagnostic trouble codes using Maserati-compatible scan tool - there should be no codes present
• Monitor oil pressure gauge shows proper pressure at idle and higher RPM
• Test drive vehicle and verify normal power delivery, no overheating, and no warning lights
• After 50-100 miles of operation, recheck all fluid levels and inspect for any new leaks
• After 500 miles, consider rechecking valve cover bolt torque as gaskets may have compressed slightly

More procedures for this vehicle