Complete disassembly, inspection, machining, and reassembly of the 2.5L I4 engine including crankshaft, pistons, camshafts, timing chain, and cylinder head.

Warnings

Tools required

Parts

• Complete gasket set (head, valve cover, oil pan, timing cover) × 1 — Use OEM specification
• Cylinder head bolts (TTY) × 1 — Use OEM specification
• Main bearing cap bolts (TTY) × 1 — Use OEM specification
• Connecting rod bolts (TTY) × 1 — Use OEM specification
• Crankshaft main bearing set (standard or oversized) × 1 — Use OEM specification
• Connecting rod bearing set (standard or oversized) × 1 — Use OEM specification
• Piston ring set × 1 — Use OEM specification
• Timing chain kit (chain, guides, tensioner) × 1 — Use OEM specification
• Oil pump assembly × 1 — Use OEM specification
• Water pump × 1 — Use OEM specification
• Thermostat with gasket × 1 — Use OEM specification
• Oil filter × 1 — Use OEM specification
• Oil drain plug crush washer × 1 — Use OEM specification
• Spark plugs × 4 — Use OEM specification
• RTV silicone gasket maker (Hyundai approved) × 1 — Use OEM specification
• Engine assembly lube × 1 — Use OEM specification
• Thread locker (medium strength) × 1 — Loctite 243 or equivalent
• Anti-seize compound × 1 — Use OEM specification

Fluids

• Hyundai Genuine 0W-20 Engine Oil — 5 qt
• Hyundai/Kia Long Life Coolant (Green) — 10 qt

Preparation

1. Remove engine from vehicle following manufacturer procedure, disconnecting all electrical connections, fuel lines, coolant hoses, exhaust, and drivetrain components
2. Mount engine securely on engine stand using proper adapter plate bolted to transmission mounting surface
3. Clean exterior of engine thoroughly to prevent contamination during disassembly
4. Drain all remaining coolant and oil into appropriate containers
5. Set up clean workspace with labeled containers for fasteners, organized by component location
6. Have digital camera or smartphone ready to photograph timing marks, component positions, and routing of chains/belts
7. Gather all machine shop contact information if machining services will be required

Procedure

1. 1

   Remove external components and accessories
   Remove valve cover, intake manifold, exhaust manifold, fuel rail, ignition coils, and all remaining sensors and brackets. Remove alternator, AC compressor mounting bracket, and power steering pump bracket if still attached. Label all electrical connectors and vacuum lines. Apply penetrating oil to exhaust manifold studs and allow to soak.
   Torque spec

   Cover Bolts16 Nm (12 lb-ft)

   Intake Manifold Bolts25 Nm (18 lb-ft)

   Exhaust Manifold Nuts30 Nm (22 lb-ft)
2. 2

   Remove timing cover and set engine to TDC
   Remove crankshaft pulley using holding tool and appropriate socket. Note: this bolt is very tight at 180 Nm and may require impact wrench. Remove timing cover bolts in reverse sequence. Rotate crankshaft to TDC on cylinder #1 (compression stroke) by aligning timing marks on camshaft sprockets and crankshaft sprocket. Photograph all timing mark positions from multiple angles before proceeding.
   ⚠Crankshaft pulley bolt requires very high torque. Use proper holding tool to prevent crankshaft rotation and potential engine damage.
   Torque spec

   Crankshaft Pulley Bolt180 Nm (133 lb-ft)

   Cover Bolts16 Nm (12 lb-ft)
3. 3

   Remove timing chain assembly
   Remove timing chain tensioner bolt and extract tensioner. Remove timing chain guides using guide bolts. Carefully remove timing chain from camshaft and crankshaft sprockets, noting orientation. Remove camshaft sprockets using holding tool. Inspect all timing components for wear, scoring, or elongation. Replace timing chain kit components as assembly.
   Torque spec

   Timing Chain Tensioner Bolt25 Nm (18 lb-ft)

   Timing Chain Guide Bolts12 Nm (9 lb-ft)
4. 4

   Remove camshaft assemblies
   Loosen camshaft bearing cap bolts gradually in reverse sequence (outside to center), in 2-3 passes to prevent warping. Remove bearing caps, keeping them in order with their original positions marked. Carefully lift camshafts from cylinder head, noting intake vs exhaust identification. Measure camshaft journal diameter, lobe height, and runout with micrometer and V-blocks. Inspect cylinder head camshaft bores for scoring or wear.
   Torque spec

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

   Remove cylinder head assembly
   Loosen cylinder head bolts in reverse torque sequence, in multiple passes to prevent warping. Remove cylinder head bolts completely (these are TTY and must be replaced). Carefully lift cylinder head from block using proper lifting points, breaking gasket seal with plastic mallet if necessary. Place cylinder head on clean padded surface. Inspect head gasket for failure patterns indicating previous issues. Clean all gasket material from deck surfaces.
   ⚠Cylinder head is aluminum and heavy. Use proper lifting technique or assistance to prevent dropping and injury.
   Torque spec

   Cylinder Head Bolts65 Nm (48 lb-ft)
6. 6

   Disassemble cylinder head and inspect valvetrain
   Using valve spring compressor, compress each valve spring and remove keepers. Release spring pressure and remove retainers, springs, and seals. Remove all valves, keeping them organized by cylinder and position. Measure valve stem diameter, valve face thickness, and spring free length. Inspect valve seats and guides in cylinder head. Check cylinder head deck surface for warpage using precision straightedge and feeler gauges (max 0.05mm). Send cylinder head to machine shop for valve job, surfacing, and pressure testing as needed.
   ⚠Valve springs are under high tension. Ensure valve spring compressor is properly seated before releasing keepers to prevent spring ejection and injury.
7. 7

   Remove oil pan and oil pump
   Remove oil pan bolts in sequence and carefully separate oil pan from block. Remove oil pump pickup tube bolts and extract pickup tube with O-ring. Remove oil pump mounting bolts and extract oil pump assembly from front of block. Inspect oil pump gears for scoring or excessive wear. Measure oil pump gear clearances and housing tolerances. Replace oil pump assembly if measurements exceed specifications.
   Torque spec

   Oil Pan Bolts12 Nm (9 lb-ft)

   Oil Pump Pickup Tube12 Nm (9 lb-ft)

   Oil Pump Bolts12 Nm (9 lb-ft)
8. 8

   Remove pistons and connecting rods
   Rotate engine to access each cylinder. Use ridge reamer to remove any ridge at top of cylinder bore before removing pistons. Mark each connecting rod and cap with cylinder number and orientation using center punch. Loosen connecting rod bolts and remove rod caps. Push piston and rod assemblies out through top of block, being careful not to damage crankshaft journals. Keep rod caps with their respective rods. Measure piston diameter, ring groove wear, and piston-to-bore clearance.
   ⚠Ridge at top of cylinder must be removed before piston extraction to prevent piston ring breakage and potential injury from sharp metal fragments.
   Torque spec

   Connecting Rod Bolts45 Nm (33 lb-ft)
9. 9

   Remove crankshaft and main bearings
   Remove flywheel bolts in star pattern and remove flywheel. Mark main bearing caps with cylinder number and direction arrow using center punch. Loosen main bearing cap bolts in reverse sequence gradually. Remove main bearing caps and set aside with their bolts. Carefully lift crankshaft from block. Remove all bearing inserts from caps and block, keeping upper and lower bearings paired. Measure crankshaft main and rod journal diameters, taper, and out-of-round using micrometer. Check crankshaft runout in V-blocks with dial indicator.
   ℹ️Crankshaft is heavy. Use proper lifting technique and have assistance available to prevent dropping.
   Torque spec

   Flywheel Bolts95 Nm (70 lb-ft)

   Main Bearing Cap Bolts75 Nm (55 lb-ft)
10. 10

    Inspect and measure engine block
    Clean engine block thoroughly with solvent and compressed air, ensuring all oil passages are clear. Measure cylinder bore diameter at multiple points (top, middle, bottom) and in two directions (parallel and perpendicular to crankshaft) using dial bore gauge. Check block deck surface for warpage using precision straightedge and feeler gauges. Inspect main bearing bores for scoring or damage. Measure main bearing bore diameter and alignment. Send block to machine shop for boring, honing, decking, or align boring as measurements indicate.
    ℹ️Keep all machine shop measurements documented. Bearing and piston selection depends on final machined dimensions.
11. 11

    Clean all components and prepare for assembly
    Thoroughly clean all components with appropriate solvents. Blow out all oil passages in block and crankshaft with compressed air. Wash block, crankshaft, connecting rods, and pistons in hot soapy water, rinse, and dry completely. Re-clean all threaded holes in block with tap or thread chaser. Lubricate all cylinder bores with assembly lube or clean engine oil. Organize all new parts including bearings, gaskets, bolts, and seals. Verify all machining has been completed and measurements are within specification.
    ℹ️Absolute cleanliness is critical. Any debris left in engine will cause immediate failure upon startup.
12. 12

    Install crankshaft and main bearings
    Install upper main bearing inserts into block, ensuring locating tabs are properly seated. Coat bearings with engine assembly lube. Carefully lower crankshaft into position. Install lower bearing inserts into main caps with assembly lube. Install main bearing caps in correct positions and orientation according to marks. Install new main bearing cap bolts and torque in sequence to 75 Nm (55 lb-ft), then tighten additional angle per TTY specification. Verify crankshaft rotates freely. Measure crankshaft endplay with dial indicator (specification typically 0.05-0.25mm).
    ⚠Main bearing cap bolts are TTY and must be new. Follow exact torque sequence and angle specifications to prevent bearing failure.
    Torque spec

    Main Bearing Cap Bolts75 Nm (55 lb-ft)
13. 13

    Install pistons and connecting rods
    Install piston rings on pistons using ring installer tool, ensuring gaps are properly staggered (typically 120 degrees apart). Install new connecting rod bearings with assembly lube. Lubricate cylinder bores, pistons, and rings with engine oil. Install piston ring compressor and carefully insert piston and rod assemblies into cylinders from top, ensuring rod orientation matches original marks. Guide connecting rod onto crankshaft journal. Install rod cap with new bolts, torque to 45 Nm (33 lb-ft), then tighten additional angle per TTY specification. Verify crankshaft still rotates freely after each piston installation.
    ⚠Connecting rod bolts are TTY and must be new. Do not reuse old bolts or catastrophic engine failure will result.
    Torque spec

    Connecting Rod Bolts45 Nm (33 lb-ft)
14. 14

    Install oil pump and oil pan
    Install new oil pump assembly with gasket or RTV as specified. Torque oil pump bolts to 12 Nm (9 lb-ft). Install oil pump pickup tube with new O-ring and torque to 12 Nm (9 lb-ft). Apply thin bead of RTV to oil pan mating surface if specified, or install new gasket. Install oil pan and torque bolts in sequence to 12 Nm (9 lb-ft). Allow RTV to cure per manufacturer specification before filling with oil. Install new oil drain plug crush washer and torque drain plug to 35 Nm (26 lb-ft).
    Torque spec

    Oil Pump Bolts12 Nm (9 lb-ft)

    Oil Pump Pickup Tube12 Nm (9 lb-ft)

    Oil Pan Bolts12 Nm (9 lb-ft)

    Oil Drain Plug35 Nm (26 lb-ft)
15. 15

    Assemble cylinder head and install
    Install valves into cylinder head with new seals, springs, retainers, and keepers using valve spring compressor. Verify all keepers are properly seated. Clean cylinder head and block deck surfaces thoroughly. Install new head gasket on block, ensuring proper orientation and alignment with dowel pins. Carefully lower cylinder head onto block. Install new cylinder head bolts with light oil on threads. Torque in proper sequence to 65 Nm (48 lb-ft), then tighten additional angle per TTY specification in sequence.
    ⚠Cylinder head bolts are TTY. Follow exact torque sequence from center outward, and specified angle tightening procedure.
    Torque spec

    Cylinder Head Bolts65 Nm (48 lb-ft)
16. 16

    Install camshafts and timing components
    Lubricate camshaft journals and lobes with assembly lube. Install camshafts into cylinder head in correct positions (intake/exhaust). Install camshaft bearing caps in correct positions and orientation. Torque camshaft bearing cap bolts in sequence from center outward to 14 Nm (10 lb-ft) in 3 passes. Install camshaft sprockets finger-tight. Install timing chain guides and torque guide bolts to 12 Nm (9 lb-ft). Install timing chain with alignment marks at TDC position. Compress timing chain tensioner, lock with pin, install tensioner, torque bolt to 25 Nm (18 lb-ft), then release pin. Verify all timing marks align correctly. Torque camshaft sprocket bolts.
    ⚠️Incorrect timing chain installation will cause severe engine damage upon startup. Triple-check all timing marks before proceeding.
    Torque spec

    Camshaft Bearing Cap Bolts14 Nm (10 lb-ft)

    Timing Chain Guide Bolts12 Nm (9 lb-ft)

    Timing Chain Tensioner Bolt25 Nm (18 lb-ft)
17. 17

    Install timing cover and external components
    Apply RTV to timing cover mating surface as specified or install gasket. Install timing cover and torque bolts in sequence to 25 Nm (18 lb-ft) for 8mm bolts. Install crankshaft pulley and torque bolt to 180 Nm (133 lb-ft) using holding tool. Install new water pump with gasket and torque bolts. Install thermostat with new gasket. Install exhaust manifold with new gaskets, applying anti-seize to studs, working from center outward and torque nuts to 30 Nm (22 lb-ft). Install intake manifold with new gaskets and torque bolts to 25 Nm (18 lb-ft). Install valve cover with new gasket and torque bolts in sequence to 10 Nm (7 lb-ft).
    Torque spec

    Cover Bolts16 Nm (12 lb-ft)

    Crankshaft Pulley Bolt180 Nm (133 lb-ft)

    Exhaust Manifold Nuts30 Nm (22 lb-ft)

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

    Install remaining accessories and prepare for installation
    Install all sensors, brackets, fuel rail, ignition coils, and wiring harnesses to engine. Install new spark plugs. Install flywheel with new bolts in star pattern, torque to 95 Nm (70 lb-ft). Fill engine with 5 quarts of Hyundai Genuine 0W-20 engine oil and new oil filter. Prime oil system by rotating crankshaft several revolutions by hand. Verify smooth rotation and no binding. Remove engine from stand and prepare for installation into vehicle.
    Torque spec

    Flywheel Bolts95 Nm (70 lb-ft)

Reassembly

1. Install engine into vehicle following manufacturer procedure, reconnecting all mounts, drivetrain components, exhaust system, and accessories
2. Reconnect all electrical connections, fuel lines, coolant hoses, and vacuum lines using photos taken during disassembly
3. Fill cooling system with 10 quarts of Hyundai/Kia Long Life Coolant (Green), bleed air from system
4. Double-check all fluid levels including oil, coolant, and check for any leaks before starting
5. Reconnect battery negative terminal

Verification

• Perform initial startup and listen for unusual noises, knocking, or valve train noise indicating assembly issues
• Monitor oil pressure gauge immediately upon startup - should rise to normal range within 5 seconds
• Allow engine to warm to operating temperature and verify no coolant, oil, or fuel leaks
• Check for proper thermostat operation and cooling fan engagement
• Perform test drive and verify proper engine operation under load, smooth acceleration, and no abnormal vibrations
• After 20-30 minutes of operation, shut down engine, allow to cool, and re-torque cylinder head bolts if manufacturer specifies
• Change engine oil and filter after initial 500 miles of break-in period
• Monitor oil consumption and check for leaks during first 1000 miles of operation

More procedures for this vehicle