Cylinder Head Resurface

This procedure covers removal, machining/resurfacing, and reinstallation of the cylinder head on the 2018-2024 Honda Accord 1.5L turbocharged engine to correct warpage or surface damage.

Warnings

Tools required

Parts

• Cylinder head gasket × 1 — Use OEM Honda specification
• Cylinder head bolt set (TTY) × 1 — Use OEM Honda specification
• Valve cover gasket × 1 — Use OEM Honda specification
• Exhaust manifold gasket × 1 — Use OEM Honda specification
• Intake manifold gasket × 1 — Use OEM Honda specification
• Timing chain tensioner gasket × 1 — Use OEM Honda specification
• Thermostat housing gasket × 1 — Use OEM Honda specification
• Spark plug tube seals × 4 — Use OEM Honda specification
• Engine oil and filter × 1 — Use OEM Honda specification

Fluids

• Honda Genuine 0W-20 — 4 qt
• Honda Type 2 Coolant (Blue) — 6 qt

Preparation

1. Ensure engine is completely cold (minimum 2 hours after last operation)
2. Disconnect negative battery terminal and wait 3 minutes for SRS system discharge
3. Drain engine coolant completely into appropriate container using radiator drain plug and lower radiator hose
4. Drain engine oil and remove oil filter
5. Remove engine cover and air intake system including turbocharger inlet ducting
6. Remove intercooler and associated piping
7. Label and disconnect all electrical connectors, vacuum lines, and fuel lines from cylinder head area
8. Relieve fuel system pressure by removing fuel pump relay and cranking engine briefly
9. Install engine support fixture to hold engine weight during disassembly
10. Place shop towels over fender areas and protect wiring harnesses from falling hardware

Procedure

1. 1

   Remove Valve Cover and Accessories
   Remove ignition coils and spark plugs, labeling positions. Disconnect PCV hoses and breather tubes from valve cover. Remove valve cover bolts in reverse of tightening sequence (outside-to-inside pattern). Carefully lift valve cover away and inspect gasket condition. Remove any accessory brackets still attached to cylinder head.
   Torque spec

   Cover Bolts15 Nm (11 lb-ft)
2. 2

   Remove Exhaust Manifold
   Disconnect oxygen sensors and turbocharger oil/coolant feed lines. Remove heat shields from exhaust manifold. Working from the cold (outer) side toward the hot (center) side, remove exhaust manifold nuts. Separate exhaust manifold and turbocharger assembly from cylinder head. Inspect studs for damage.
   ⚠Even on a cold engine, exhaust studs may be brittle from heat cycling. Apply penetrating oil 30 minutes before removal to prevent breakage.
   Torque spec

   Exhaust Manifold Nuts30 Nm (22 lb-ft)
3. 3

   Remove Intake Manifold
   Disconnect throttle body electrical connector and coolant hoses. Remove fuel rail with injectors as an assembly (do not disconnect injectors unless necessary). Remove intake manifold bolts in a crisscross pattern from outside to inside. Lift intake manifold away from cylinder head. Inspect manifold mounting surface and injector seals.
   Torque spec

   Intake Manifold Bolts25 Nm (18 lb-ft)
4. 4

   Set Engine to TDC and Lock Timing Chain
   Rotate crankshaft clockwise using crankshaft pulley bolt until cylinder #1 is at top dead center (TDC) on compression stroke. Verify timing marks on camshaft sprockets align with timing cover marks. Install timing chain locking tools or wire-tie chain to sprockets to prevent chain-to-sprocket movement. Mark chain-to-sprocket relationship with paint marker as backup reference.
   ⚠️Timing chain position is critical. Take photographs of all timing marks and chain routing before proceeding. Loss of timing alignment will cause valve-to-piston contact.
5. 5

   Remove Timing Chain Components from Cylinder Head
   Remove timing chain upper guide and tensioner arm. Hold camshaft sprockets with chain holder tool and remove camshaft sprocket bolts. Carefully lift camshaft sprockets off camshafts while keeping chain engaged on crankshaft sprocket below. Secure chain to prevent dropping into timing cover using wire or locking tool. Remove timing chain rear cover bolts from cylinder head area.
   Torque spec

   Mounting Bolts26 Nm (19 lb-ft)
6. 6

   Remove Camshafts and Valve Components
   Loosen camshaft bearing cap bolts in sequence from outer caps toward center in multiple passes (2-3 turns per pass) to prevent warping. Remove bearing caps and label by position and orientation. Lift camshafts from cylinder head and store in order. Remove rocker arms and valve lifters, organizing in numbered trays to maintain original positions. Inspect all components for wear or damage.
   ⚠Camshaft bearing caps are directional and position-specific. Mark each cap clearly before removal or cam seizure may occur during reassembly.
7. 7

   Remove Cylinder Head Bolts and Head
   Loosen cylinder head bolts in reverse of tightening sequence (start from outside, work toward center) in 2-3 passes to gradually release tension. Remove all cylinder head bolts and discard (TTY bolts cannot be reused). Carefully lift cylinder head straight up off engine block, using lifting eyes if equipped. Do not pry between head and block surfaces. Place head gasket-side-up on clean work surface padded with shop towels.
   ⚠Cylinder head weighs approximately 50 lbs. Use proper lifting technique or assistant to prevent injury or head damage from dropping.
   Torque spec

   Cylinder Head Bolts65 Nm (48 lb-ft)
8. 8

   Clean and Inspect Cylinder Head
   Remove old head gasket material from cylinder head surface using plastic gasket scraper (never metal tools). Clean all bolt holes, coolant passages, and oil return passages with brake cleaner. Inspect head for cracks using dye penetrant or magnetic particle testing if available. Check valve seats and combustion chamber for damage. Measure cylinder head flatness using precision straightedge and feeler gauge at multiple points lengthwise, crosswise, and diagonally.
   ℹ️Honda specifies maximum warpage of 0.002 inch (0.05mm). Any measurement exceeding this requires resurfacing. Maximum material removal is limited - consult machine shop for specifications.
9. 9

   Machine Shop Resurfacing
   Transport cylinder head to qualified machine shop for resurfacing. Specify Honda maximum warpage tolerance and material removal limits. Request surface finish of 60-80 RA for multi-layer steel gasket compatibility. Have shop perform valve seat inspection and lapping if requested. Upon return, verify final flatness measurement is within 0.001 inch specification and surface finish meets requirements. Clean head thoroughly after machining to remove all metal particles and cutting fluid residue.
   ℹ️Resurfacing changes deck height and may affect compression ratio slightly. Most machine shops remove 0.003-0.010 inch which is within acceptable limits for this engine.
10. 10

    Prepare Engine Block Surface
    With cylinder head removed, clean engine block deck surface thoroughly using plastic scraper. Remove all old gasket material without scratching aluminum surface. Clean bolt holes in block using thread chaser or tap, then blow out with compressed air. Verify all bolt holes are dry and free of oil or coolant. Inspect block deck for warpage using straightedge. Cover cylinders with clean shop towels to prevent debris entry. Do not rotate crankshaft during reassembly to maintain timing position.
    ⚠Any oil or coolant in cylinder head bolt holes will cause false torque readings and potential bolt/thread failure. Ensure holes are completely dry.
11. 11

    Install New Head Gasket and Position Cylinder Head
    Remove protective towels from cylinder bores. Position new cylinder head gasket on block, aligning all dowel pins and coolant/oil passages. Verify gasket orientation marking (TOP or OBEN) faces upward. Carefully lower cylinder head onto block, using lifting eyes and guiding onto dowel pins. Ensure head seats completely flat on gasket without shifting gasket position. Install new cylinder head bolts finger-tight in sequence.
    ⚠Do not apply any sealant to multi-layer steel head gasket. Gasket must be installed completely dry per Honda specifications.
12. 12

    Torque Cylinder Head Bolts
    Using proper tightening sequence (center outward pattern per Honda service manual), torque all cylinder head bolts to 65.0 Nm (48.0 lb-ft) in sequence. Then, using angle gauge, tighten all bolts an additional 90 degrees (1/4 turn) in same sequence. Follow with final angle tightening of 90 degrees (1/4 turn) in sequence for total of 180 degrees beyond initial torque. Verify each bolt reaches specified angle without binding or unusual resistance.
    ⚠️TTY bolt procedure is critical. Sequence is: 48 lb-ft, then +90°, then +90° (total 180° angle). Skipping angle steps or incorrect sequence will cause head gasket failure.
    Torque spec

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

    Reinstall Valvetrain Components
    Lubricate all valve lifters and rocker arms with fresh engine oil. Install lifters and rocker arms in their original positions using labeled organization from disassembly. Apply engine assembly lube to camshaft journals and lobes. Install camshafts in correct positions (intake and exhaust marked), aligning timing marks. Install camshaft bearing caps in original positions and orientation. Torque bearing cap bolts in sequence from center outward in multiple passes (2-3 passes) to specified torque.
    Torque spec

    Mounting Bolts26 Nm (19 lb-ft)
14. 14

    Reinstall Timing Chain and Components
    Verify crankshaft is still at TDC position. Install camshaft sprockets onto camshafts with timing chain properly engaged, aligning all timing marks exactly as photographed during disassembly. Install and torque camshaft sprocket bolts while holding sprockets. Install timing chain guide and tensioner arm. Install timing chain tensioner (release tensioner lock after installation). Remove timing locking tools and manually rotate engine 2 complete revolutions clockwise, verifying all timing marks realign at TDC. Install timing chain rear cover with new gasket.
    ⚠️Recheck timing marks three times before proceeding. Incorrect timing will destroy engine immediately upon startup.
    Torque spec

    Gasket Bolts19 Nm (14 lb-ft)

    Mounting Bolts26 Nm (19 lb-ft)
15. 15

    Reinstall Intake and Exhaust Manifolds
    Install new intake manifold gasket and position intake manifold onto cylinder head. Torque intake manifold bolts to 25.0 Nm (18.0 lb-ft) in crisscross pattern from center outward. Reinstall fuel rail and injectors. Apply anti-seize compound to exhaust manifold studs. Install new exhaust manifold gasket and position exhaust manifold/turbocharger assembly. Torque exhaust manifold nuts to 30.0 Nm (22.0 lb-ft) working from hot (center) to cold (outer) positions. Reconnect turbocharger oil and coolant lines.
    Torque spec

    Intake Manifold Bolts25 Nm (18 lb-ft)

    Exhaust Manifold Nuts30 Nm (22 lb-ft)
16. 16

    Reinstall Valve Cover and Accessories
    Install new spark plug tube seals in valve cover. Install new valve cover gasket in cover groove, ensuring proper seating. Position valve cover on cylinder head and install bolts finger-tight. Torque valve cover bolts to 10.0 Nm (7.0 lb-ft) in proper sequence (center outward). Install spark plugs and ignition coils. Reconnect all electrical connectors, vacuum lines, PCV hoses, and breather tubes. Reinstall intercooler piping and air intake system. Reinstall engine cover.
    Torque spec

    Cover Bolts15 Nm (11 lb-ft)
17. 17

    Refill Fluids and Final Checks
    Install new oil filter and refill engine with 4.0 quarts Honda Genuine 0W-20 oil. Refill cooling system with 6.0 quarts Honda Type 2 (Blue) coolant through radiator and reservoir. Reconnect battery negative terminal. Double-check all electrical connections, hose clamps, and bolt torques. Verify no tools or parts remain in engine bay.
    ℹ️Cooling system may require bleeding procedure to remove air pockets. Run engine with heater on full to circulate coolant and monitor level.

Reassembly

1. All torque specifications must be followed exactly, especially TTY cylinder head bolts which require initial torque plus angle tightening
2. Timing chain alignment is critical - verify timing marks three times before starting engine
3. Use only new gaskets and seals throughout reassembly - never reuse head gasket or head bolts
4. Apply anti-seize compound only to exhaust manifold studs, never to head bolts or gasket surfaces
5. Maintain organization of valvetrain components to ensure installation in original positions

Verification

• Before first start: rotate engine manually 2 full revolutions and recheck timing marks align perfectly at TDC
• Check for proper oil pressure within 5 seconds of initial startup (oil pressure light should extinguish)
• Monitor for coolant, oil, or exhaust leaks during first 5 minutes of runtime at idle
• Allow engine to reach full operating temperature and verify cooling fans cycle properly
• Check coolant level after engine cools and top off as needed, repeat after first 50 miles
• Perform test drive and monitor for abnormal noises, overheating, or warning lights
• Recheck valve cover bolt torque and all external fasteners after first heat cycle
• Change engine oil and filter after first 500 miles following cylinder head work

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

Chasing one of these codes and not sure which part is guilty? Ask a master mechanic about YOUR car →

More procedures for this vehicle