Head Gaskets - Both

Complete replacement of both cylinder head gaskets on the 8.3L V10 engine, including removal of intake manifold, exhaust manifolds, valve covers, timing cover, timing chains, camshafts, and cylinder heads.

Warnings

Tools required

Parts

• Head gasket - left bank × 1 — OEM Mopar/Dodge Viper 8.3L specification
• Head gasket - right bank × 1 — OEM Mopar/Dodge Viper 8.3L specification
• Cylinder head bolts - set of 10 per head × 2 — Use OEM specification - TTY bolts, not reusable
• Valve cover gasket - left × 1 — Use OEM specification
• Valve cover gasket - right × 1 — Use OEM specification
• Intake manifold gasket set × 1 — Use OEM specification
• Exhaust manifold gasket - left bank × 1 — Use OEM specification
• Exhaust manifold gasket - right bank × 1 — Use OEM specification
• Timing cover gasket × 1 — Use OEM specification
• Timing cover seal × 1 — Use OEM specification
• Crankshaft front seal × 1 — Use OEM specification
• Oil drain plug crush washer × 1 — Use OEM specification
• Engine coolant (Zerex G-05 HOAT 50/50) × 1 — 19 quarts total capacity
• Engine oil (0W-40 full synthetic) × 1 — 11 quarts total capacity
• RTV sealant (high-temp) × 1 — Mopar or equivalent specification

Fluids

• 0W-40 full synthetic — 11 qt
• Zerex G-05 HOAT 50/50 — 19 qt

Preparation

1. Ensure engine is completely cold to touch before beginning work
2. Disconnect negative battery cable and secure away from terminal
3. Remove engine cover panels and decorative covers
4. Place vehicle on level ground with parking brake engaged
5. Position large coolant drain pan under engine - this system holds 19 quarts
6. Document or photograph all electrical connector positions and routing before disconnection
7. Have replacement parts, gaskets, and new head bolts on hand before starting - this is not a job to pause mid-way
8. Clear adequate workspace around engine bay - you will need room to maneuver large components

Procedure

1. 1

   Drain Coolant and Oil
   Open radiator drain valve and remove radiator cap to drain coolant system completely into drain pan. Once coolant flow stops, remove oil drain plug and drain engine oil into separate pan. Install new crush washer on drain plug and reinstall finger-tight for now (will torque during final reassembly). Draining oil now prevents contamination during head gasket work. Note: Fill cooling system with the factory-specified coolant volume (verify total capacity from the Viper 8.3L service manual) of Zerex G-05 HOAT 50/50 coolant through radiator and overflow reservoir.
2. 2

   Remove Intake System and Throttle Body
   Remove air intake tube and air filter housing assembly. Disconnect throttle cables and cruise control cable from throttle body. Disconnect electrical connectors from throttle position sensor and idle air control valve. Remove throttle body mounting bolts and remove throttle body assembly. Disconnect all vacuum lines from intake manifold, marking positions for reassembly. Disconnect fuel supply and return lines at fuel rail (relieve fuel system pressure first by removing fuel pump fuse and cranking engine briefly).
3. 3

   Remove Fuel Rails and Injectors
   Disconnect electrical connectors from all 10 fuel injectors. Remove fuel rail mounting bolts (typically 4 bolts per rail). Carefully lift fuel rails with injectors attached from intake manifold. Cap or plug all fuel injector ports in intake manifold to prevent debris entry. Store fuel rail assemblies in clean area.
4. 4

   Remove Intake Manifold
   Disconnect all remaining electrical connectors, vacuum lines, and breather hoses from intake manifold. Remove intake manifold mounting bolts in reverse order of tightening sequence (work from outside toward center). There are approximately 16 bolts securing the intake manifold on this engine. Carefully lift intake manifold straight up and off cylinder heads. The manifold is aluminum and relatively light but bulky - have a clean workspace ready to set it down.
5. 5

   Remove Valve Covers
   Disconnect any electrical connectors or breather hoses attached to valve covers. Remove valve cover bolts from both left and right covers (10 bolts per cover). Carefully lift valve covers off, tapping gently with dead blow hammer if stuck. Inspect valve train for any obvious damage or unusual wear patterns. Leave rocker arms and pushrods in place for now - their removal will come after exhaust manifold removal. Note this is a pushrod (OHV) engine with a single in-block camshaft.
6. 6

   Remove Exhaust Manifolds
   Working from underneath vehicle if necessary, disconnect exhaust pipes from both exhaust manifolds at flange connections. Remove exhaust manifold mounting nuts from both banks - verify the number of studs/nuts per manifold against the Viper 8.3L service manual before ordering hardware. Left and right manifolds can be challenging to access; use swivel sockets and extensions as needed. Once all nuts are removed, carefully work exhaust manifolds free from heads.
   Torque spec

   Exhaust Manifold Nuts34 Nm (25 lb-ft)
7. 7

   Remove Accessory Drive Components
   Remove serpentine belt by releasing tensioner. Remove alternator mounting bolts and reposition alternator with wires still attached. Remove power steering pump mounting bolts and secure pump aside without disconnecting hydraulic lines. Remove A/C compressor mounting bolts and secure compressor aside without disconnecting refrigerant lines. Remove water pump (4 bolts). These components must be clear to access timing cover.
8. 8

   Remove Harmonic Balancer and Timing Cover
   Remove crankshaft pulley center bolt using breaker bar (verify factory torque spec from Viper 8.3L service manual before relying on any assumed value). Use harmonic balancer puller to remove balancer from crankshaft - do NOT use jaw-type pullers that grip outer edge as this can damage the balancer. With balancer removed, remove timing cover bolts (approximately 15 bolts of varying lengths - mark positions). Carefully pry timing cover off using plastic pry tools, working around perimeter. Remove old timing cover gasket and seal.
   Torque spec

   Crankshaft Pulley Bolt180 Nm (133 lb-ft)
9. 9

   Mark and Verify Timing Alignment
   Rotate crankshaft to TDC on cylinder #1 (both intake and exhaust valves closed, rocker arms loose). For a head gasket job on this pushrod engine, timing chain alignment is not disturbed since the in-block camshaft and single timing chain remain in place. If timing verification is required, align the single crankshaft sprocket mark with the single camshaft sprocket mark per the Viper 8.3L service manual. Use paint marker or scribe to mark current position of all timing components relative to each other AND relative to engine block/heads. Take photographs from multiple angles. This documentation is CRITICAL for reassembly timing verification.
   ⚠Timing mark verification is the most critical step. Incorrect timing during reassembly will cause valve-to-piston contact and destroy the engine. Double and triple-check all marks.
10. 10

    Remove Timing Chains and Camshaft Sprockets
    NOTE: The 8.3L Viper V10 uses a single in-block camshaft driven by a single timing chain and sprocket from the crankshaft. For a head gasket replacement, the camshaft and timing chain do not need to be removed. If timing cover work is required, remove the single camshaft sprocket bolt and slide the single timing chain and sprockets off. Disregard references to multiple bank-specific chains and four camshaft sprockets. from engine. Remove camshaft sprockets by sliding off camshaft snouts.
    Torque spec

    Timing Chain Tensioner Bolt25 Nm (18 lb-ft)

    Camshaft Sprocket Bolt80 Nm (59 lb-ft)
11. 11

    Remove Rocker Arms and Pushrods
    Remove rocker arm mounting bolts from all 20 rocker arms (10 per bank). Keep rocker arms organized by cylinder and position (intake/exhaust) using labeled storage. Lift out all pushrods and store in organized manner - pushrods MUST return to their original positions. Inspect pushrod ends and rocker arm contact surfaces for unusual wear. Store all valve train components in clean, protected area.
12. 12

    Remove Camshafts
    NOTE: The 8.3L Viper V10 is a pushrod (OHV) engine with a single camshaft located in the engine block valley. There are no overhead camshafts or camshaft bearing caps to remove. This step does not apply and should be deleted. For a head gasket job, the single in-block camshaft is not disturbed. Loosen bolts gradually in multiple passes to prevent binding or distortion. Once all cap bolts are removed, lift bearing caps off. Carefully lift each camshaft straight up out of cylinder head. Inspect camshaft lobes and journals for scoring or unusual wear. Store camshafts in protected area where they cannot roll or be damaged.
13. 13

    Remove Cylinder Head Bolts
    Remove cylinder head bolts from both heads in reverse order of tightening sequence (typically from outer bolts toward center). There are 10 head bolts per cylinder head. Loosen head bolts gradually in multiple passes using cross-pattern sequence to prevent head warping. Once all bolts are loose, remove bolts completely and discard - these are TTY (torque-to-yield) bolts and CANNOT be reused. Using new head bolts is mandatory for this repair.
    ⚠️Head bolts MUST be replaced with new bolts. Torque-to-yield bolts are stretched during installation and lose their clamping ability if reused. Using old bolts will result in head gasket failure.
14. 14

    Remove Cylinder Heads
    With all head bolts removed, carefully break heads free from engine block using plastic pry points (do not pry on gasket surfaces). You may need to tap heads gently with dead blow hammer to break gasket seal. Once free, lift cylinder heads straight up off engine block. Heads are heavy (approximately 50-60 lbs each) - use assistance or hoist if needed. Place heads on clean padded surface with gasket surface facing up.
    ⚠Cylinder heads are heavy and awkward. Use proper lifting technique and assistance to prevent dropping or damaging components.
15. 15

    Clean and Inspect Gasket Surfaces
    Remove all old gasket material from cylinder head mating surfaces and engine block deck using plastic scrapers. Do NOT use metal scrapers that can gouge aluminum surfaces. Use gasket remover chemical to dissolve stubborn gasket residue. Clean all surfaces thoroughly with brake cleaner and lint-free cloths until completely clean and dry. Inspect cylinder head mating surfaces with machinist straight edge and feeler gauges - maximum allowable warpage is typically 0.002 inch over entire surface. Check engine block deck surface similarly. If warpage exceeds specification, cylinder heads must be professionally resurfaced before reinstallation.
    ⚠Any debris, old gasket material, or surface imperfections will cause the new head gaskets to fail. Mating surfaces must be absolutely clean and flat.
16. 16

    Install New Head Gaskets and Cylinder Heads
    Verify engine block deck surface is completely clean and dry. Install new head gaskets onto engine block, carefully aligning all coolant and oil passages - gaskets are marked LEFT and RIGHT and have definite front-to-rear orientation. Do NOT use any sealant on head gaskets unless specifically required by gasket manufacturer. Carefully lower cylinder heads onto block, aligning heads with dowel pins. Ensure heads seat fully onto gaskets before installing bolts.
    ℹ️Head gaskets are orientation-specific. Verify LEFT/RIGHT and FRONT/REAR orientation before installation. Backwards gaskets will block coolant or oil passages.
17. 17

    Install and Torque Cylinder Head Bolts
    Install new cylinder head bolts finger-tight in all positions on both heads. Using torque wrench and torque angle gauge, tighten head bolts in proper sequence (typically from center outward in spiral pattern). Tightening procedure: Follow the exact torque-plus-angle sequence specified in the factory Viper 8.3L service manual — DO NOT use generic values. Verify each step (initial seating torque, intermediate torque, and final angle-torque passes) against Mopar documentation before proceeding, as incorrect head bolt torque will cause gasket failure. Verify each bolt has been properly torqued and angled.
    ⚠Head bolt tightening sequence and torque procedure must be followed exactly. Improper torque or sequence will result in head gasket failure or head warping.
    Torque spec

    Cylinder Head Bolts88 Nm (65 lb-ft)
18. 18

    Install Camshafts
    NOTE: The 8.3L V10 is a pushrod engine with a single in-block camshaft that is not removed during head gasket service. This step does not apply and should be deleted. Proceed directly to installing pushrods and rocker arms. 14.0 Nm (10.0 lb-ft) for all camshaft cap bolts. Verify camshafts rotate freely by hand after installation.
    Torque spec

    Camshaft Cap Bolts14 Nm (10 lb-ft)
19. 19

    Install Pushrods and Rocker Arms
    Install pushrods in their original positions, ensuring lower end seats properly in lifter cup. Lubricate rocker arm pivot points and valve stem tips with assembly lube. Install rocker arms in original positions over pushrods and valve stems. Rotate crankshaft as needed so cam lobe is pointing away from rocker arm (valve fully closed) before tightening each rocker arm bolt. Torque rocker arm fasteners to the factory-specified value from the Viper 8.3L service manual (verify before assembly). Verify each pushrod spins freely by hand after rocker arm installation.
    Torque spec

    Rocker Arm Bolts30 Nm (22 lb-ft)
20. 20

    Install Timing Components
    Install camshaft sprockets onto camshaft snouts, aligning keyways. Install crankshaft sprocket if removed. Route timing chains over sprockets, aligning all timing marks per documentation from disassembly: crankshaft at TDC, both camshaft sprockets aligned with their respective marks. Install and hand-tighten camshaft sprocket bolts (holding camshaft hex to prevent rotation), but do NOT fully torque yet. Install timing chain guides. Install timing chain tensioners (compress tensioner plunger and install retaining pin before installation, then remove pin after tensioner is bolted in place). Torque tensioner bolts to 25.0 Nm (18.0 lb-ft). NOW torque camshaft sprocket bolts to 80.0 Nm (59.0 lb-ft) while holding camshaft hex. Rotate engine two complete revolutions by hand and verify all timing marks realign perfectly.
    ⚠️Verify timing mark alignment after rotating engine two full revolutions. If marks do not realign, timing is incorrect and must be corrected before proceeding.
    Torque spec

    Timing Chain Tensioner Bolt25 Nm (18 lb-ft)

    Camshaft Sprocket Bolt80 Nm (59 lb-ft)
21. 21

    Install Timing Cover
    Clean timing cover mating surface thoroughly. Install new crankshaft front seal into timing cover using seal driver or appropriate socket. Apply thin bead of RTV sealant to timing cover where specified by factory service manual (typically at block-to-oil pan junction and block-to-head junctions). Install new timing cover gasket. Position timing cover onto engine, aligning over crankshaft snout and dowel pins. Install all timing cover bolts finger-tight, then torque in sequence to 25.0 Nm (18.0 lb-ft) for 8mm bolts. Allow RTV to cure per manufacturer instructions before adding fluids.
    Torque spec

    Timing Cover Bolts - 8mm25 Nm (18 lb-ft)
22. 22

    Install Harmonic Balancer
    Lubricate crankshaft snout and inside of harmonic balancer with clean engine oil. Slide harmonic balancer onto crankshaft, aligning keyway. Using harmonic balancer installation tool (or carefully tap with dead blow hammer and large socket), seat balancer fully onto crankshaft. Install crankshaft pulley bolt and torque to the factory-specified value from the Viper 8.3L service manual (verify before assembly — do not rely on an assumed 180 Nm). This bolt may require impact wrench for installation.
    Torque spec

    Crankshaft Pulley Bolt180 Nm (133 lb-ft)
23. 23

    Install Water Pump and Accessory Components
    Install water pump with new gasket (4 bolts). Reinstall A/C compressor to mounting bracket. Reinstall power steering pump to mounting bracket. Reinstall alternator to mounting bracket. Reconnect all electrical connections to these components. Install and tension serpentine belt using tensioner.
24. 24

    Install Exhaust Manifolds
    Install new exhaust manifold gaskets onto cylinder head studs. Position exhaust manifolds onto studs and install all manifold nuts finger-tight. Torque exhaust manifold nuts in sequence from center outward to 34.0 Nm (25.0 lb-ft). Reconnect exhaust pipes to manifold flanges with new gaskets and hardware.
    Torque spec

    Exhaust Manifold Nuts34 Nm (25 lb-ft)
25. 25

    Install Valve Covers
    Install new valve cover gaskets into valve cover grooves (use small dabs of RTV to hold gaskets in place if needed). Position valve covers onto cylinder heads and install all valve cover bolts finger-tight. Torque valve cover bolts in sequence from center outward to 10.0 Nm (7.0 lb-ft). Do not overtighten - these are aluminum covers with rubber gaskets. Reconnect any breather hoses or electrical connections to valve covers.
    Torque spec

    Valve Cover Bolts10 Nm (7 lb-ft)
26. 26

    Install Intake Manifold
    Install new intake manifold gaskets onto cylinder heads - gaskets may have alignment pins or tabs. Apply small bead of RTV sealant at front and rear block-to-head junctions as specified. Carefully lower intake manifold into position, ensuring all gaskets remain properly seated. Install all intake manifold bolts finger-tight. Torque intake manifold bolts in sequence from center outward to 24.0 Nm (18.0 lb-ft). Reconnect all vacuum lines, breather hoses, and electrical connections to intake manifold.
    Torque spec

    Intake Manifold Bolts24 Nm (18 lb-ft)
27. 27

    Install Fuel System and Throttle Body
    Remove plugs from fuel injector ports in intake manifold. Lubricate fuel injector O-rings with clean engine oil. Install fuel rails with injectors into intake manifold, pressing firmly to seat all injectors. Install fuel rail mounting bolts and tighten securely. Reconnect all fuel injector electrical connectors. Reconnect fuel supply and return lines. Install throttle body with new gasket, reconnect all electrical connections, throttle cables, and vacuum lines. Reinstall air filter housing and intake tube.
28. 28

    Refill Fluids and Final Checks
    Torque oil drain plug to 35.0 Nm (26.0 lb-ft) with new crush washer. Fill engine with the factory-specified oil capacity (verify from the Viper 8.3L service manual) of the manufacturer-recommended synthetic engine oil grade. Close radiator drain valve. Fill cooling system with 19 quarts of Zerex G-05 HOAT 50/50 coolant through radiator and overflow reservoir. Reconnect battery negative cable. Reinstall engine covers. Double-check that all electrical connectors, vacuum lines, and hoses have been reconnected. Verify no tools or parts have been left in engine bay.
    Torque spec

    Oil Drain Plug35 Nm (26 lb-ft)

Reassembly

1. Installation is covered in the main procedure steps above
2. Torque specifications are critical - use calibrated torque wrench for all fasteners
3. All torque-to-yield components (head bolts) must be replaced with new parts
4. Timing mark alignment must be verified multiple times during assembly
5. Allow RTV sealant to cure before starting engine if specified by sealant manufacturer

Verification

• Before starting engine: Rotate crankshaft two complete revolutions by hand (using socket on crankshaft bolt) to verify no valve-to-piston interference and proper timing chain operation. Engine should rotate smoothly with no binding
• Verify all timing marks still align after manual rotation test
• Check engine oil level on dipstick - should be at FULL mark
• Check coolant level in reservoir - should be at COLD FULL mark
• Verify all electrical connectors are secure and all vacuum lines are reconnected
• Start engine and listen for unusual noises - should idle smoothly with no ticking, grinding, or rattling
• Verify oil pressure gauge shows normal pressure within 5 seconds of starting
• Monitor engine temperature - should reach normal operating temperature with thermostat opening (upper radiator hose becomes hot)
• Check for coolant leaks around head gasket areas, timing cover, and all hose connections
• Check for oil leaks around valve covers, timing cover, and all gasket areas
• Check for exhaust leaks at manifold flanges and exhaust pipe connections
• After 20 minutes of operation at normal temperature, shut off engine and allow to cool. Recheck coolant level and add if necessary (system will purge air)
• Road test vehicle under light load, monitoring temperature gauge for any overheating
• After 500 miles, recheck valve cover bolt torque and check for any fluid leaks

More procedures for this vehicle