Long Block Replacement

Complete removal and replacement of the long block assembly on a 2015 Kia Forte 1.8L I4 engine, including transfer of external components from old engine to new long block.

Warnings

Tools required

Parts

• Long block assembly (1.8L Nu engine) × 1 — Use OEM specification
• Engine oil and filter × 1 — Use OEM specification
• Coolant × 1 — Use OEM specification
• Exhaust manifold gasket × 1 — Use OEM specification
• Intake manifold gasket × 1 — Use OEM specification
• Valve cover gasket with grommets × 1 — Use OEM specification
• Timing cover gasket × 1 — Use OEM specification
• Oil pan gasket × 1 — Use OEM specification
• Oil drain plug crush washer × 1 — Use OEM specification
• Transmission-to-engine gasket/seal × 1 — Use OEM specification
• Engine mount bolts/hardware × 1 — Use OEM specification
• Anti-seize compound × 1 — Copper-based high temperature

Fluids

• Kia Genuine 5W-20 engine oil — 4.5 qt
• Hyundai/Kia Long Life Coolant (Green) — 7.5 qt
• Kia SP-IV-M ATF — 1 qt

Preparation

1. Disconnect negative battery cable and secure away from terminal
2. Raise vehicle on lift or jack stands at all four corners ensuring stable support
3. Remove engine under covers and splash shields
4. Drain engine oil and coolant into appropriate containers
5. Relieve fuel system pressure by removing fuel pump fuse and cranking engine until it stalls
6. Have AC system professionally evacuated and recovered
7. Remove hood for clearance (mark hinge positions for reinstallation)
8. Support vehicle weight on frame, not suspension components

Procedure

1. 1

   Remove intake and exhaust systems
   Disconnect air intake tube from throttle body. Remove air filter housing assembly. Disconnect all vacuum lines from intake manifold (label each). Disconnect throttle cable and electrical connections at throttle body. Remove intake manifold bolts and lift manifold away. Disconnect oxygen sensors from exhaust manifold. Remove exhaust manifold heat shield. Remove exhaust manifold nuts working from hot center to cold outer ends. Remove exhaust manifold and gasket.
   Torque spec

   Intake Manifold Bolts25 Nm (18 lb-ft)

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

   Disconnect engine electrical and accessories
   Disconnect all engine harness connectors including alternator, starter, coolant temperature sensors, oil pressure sensor, camshaft position sensor, crankshaft position sensor, throttle position sensor, MAF sensor, and ignition coil connectors. Remove accessory drive belt. Remove alternator mounting bolts and secure alternator aside. Remove power steering pump bolts and secure pump aside without disconnecting hydraulic lines. Remove AC compressor mounting bolts and secure compressor aside without disconnecting refrigerant lines.
   Torque spec

   Sensor Bolts10 Nm (8 lb-ft)

   Mounting Bolts26 Nm (19 lb-ft)
3. 3

   Disconnect cooling system
   Disconnect upper and lower radiator hoses at engine. Disconnect heater hoses at firewall connections. Disconnect coolant bypass hose if equipped. Remove thermostat housing if transferring to new long block. Cap all open coolant passages to prevent debris entry.
4. 4

   Disconnect fuel system
   Using fuel line disconnect tools, separate fuel supply and return lines at engine connections. Have shop towels ready for residual fuel spillage. Cap all fuel line openings immediately to prevent contamination and fuel evaporation.
5. 5

   Separate transmission from engine
   Support transmission with transmission jack or suitable support. Remove starter motor. Remove transmission-to-engine mounting bolts (note different lengths and positions). On automatic transmission models, mark flexplate-to-torque converter relationship and remove torque converter bolts through starter opening. Carefully separate transmission from engine, ensuring torque converter remains with transmission. Support transmission securely once separated.
   Torque spec

   Transmission-to-Engine Bolts55 Nm (41 lb-ft)
6. 6

   Remove engine mounts
   Support engine weight using engine hoist attached to factory lifting eyes or strong engine block points. Remove passenger side engine mount through-bolt and mounting bracket. Remove driver side engine mount through-bolt and mounting bracket. Remove rear engine mount/torque strut. Verify all electrical, fuel, coolant, and vacuum connections are disconnected before proceeding.
   Torque spec

   Mounting Bolts26 Nm (19 lb-ft)
7. 7

   Extract engine from vehicle
   Using engine hoist with leveler, slowly raise engine while monitoring clearance around firewall, radiator support, and frame rails. Adjust engine angle as needed for clearance. Tilt engine forward slightly as it clears transmission input shaft. Once clear of engine bay, lower engine onto sturdy work surface. Inspect engine bay for any components left behind that should have been removed.
8. 8

   Transfer external components to new long block
   Remove and transfer the following components from old engine to new long block: flywheel/flexplate (inspect for cracks, replace if necessary), clutch assembly if manual transmission, timing cover, water pump, oil pump if external, oil pan, valve cover, fuel rail and injectors, coil packs, all sensors (camshaft position, crankshaft position, oil pressure, coolant temperature), thermostat housing, engine mounts/brackets, dipstick tube, and any other external accessories. Clean all gasket surfaces thoroughly with plastic scrapers. Inspect all components for wear before transferring.
   Torque spec

   Flywheel Bolts95 Nm (70 lb-ft)

   Oil Pan Bolts12 Nm (9 lb-ft)

   Cover Bolts15 Nm (11 lb-ft)

   Gasket Bolts19 Nm (14 lb-ft)

   Sensor Bolts10 Nm (8 lb-ft)
9. 9

   Install flywheel and timing components
   Install flywheel/flexplate onto new long block crankshaft using new bolts. Tighten in star pattern to specification. If timing components are not pre-installed on long block, install timing chain, guides, and tensioner according to factory timing marks. Install timing chain tensioner with compression pin/clip, then remove pin after bolt is torqued. Install timing cover with new gasket, tightening bolts in proper sequence. Install valve cover with new gasket and grommets, tightening in sequence from center outward.
   Torque spec

   Flywheel Bolts95 Nm (70 lb-ft)

   Timing Chain Tensioner Bolt25 Nm (18 lb-ft)

   Cover Bolts15 Nm (11 lb-ft)
10. 10

    Install oil pan and prepare for installation
    Install oil pan with new gasket. Tighten oil pan bolts in crisscross pattern from center outward. Install new oil drain plug with new crush washer. Install oil filter. Apply anti-seize compound to exhaust manifold studs. Attach engine hoist to lifting points on assembled engine. Verify all external components are properly torqued and secured.
    Torque spec

    Oil Pan Bolts12 Nm (9 lb-ft)

    Oil Drain Plug35 Nm (26 lb-ft)
11. 11

    Install engine into vehicle
    Using engine hoist with leveler, carefully lower engine into engine bay. Angle engine to align with transmission while clearing firewall and frame rails. Guide engine onto transmission input shaft (or over torque converter on automatic). Align engine mount brackets with frame mounting points. Install engine mount bolts and torque to specification once engine is properly seated. Remove engine hoist only after all mounts are secured.
    Torque spec

    Mounting Bolts26 Nm (19 lb-ft)
12. 12

    Reconnect transmission and install manifolds
    Install transmission-to-engine bolts and torque in star pattern. On automatic transmission, install torque converter bolts according to alignment marks made during removal. Install starter motor. Install exhaust manifold with new gasket, applying anti-seize to threads, torquing nuts from center outward. Install exhaust manifold heat shield. Reconnect oxygen sensors. Install intake manifold with new gasket and torque bolts to specification.
    Torque spec

    Transmission-to-Engine Bolts55 Nm (41 lb-ft)

    Exhaust Manifold Nuts30 Nm (22 lb-ft)

    Intake Manifold Bolts25 Nm (18 lb-ft)
13. 13

    Reconnect accessories and systems
    Install and tension accessory drive belt. Reconnect alternator, power steering pump, and AC compressor to mounting brackets. Reconnect all electrical connectors to sensors, ignition coils, injectors, alternator, and starter. Reconnect fuel supply and return lines ensuring proper engagement of quick-disconnect fittings. Reconnect all vacuum lines according to labels/photos. Reconnect coolant hoses (upper radiator, lower radiator, heater, and bypass).
14. 14

    Fill fluids and perform initial startup
    Fill engine with 4.5 quarts of Kia Genuine 5W-20 oil. Fill cooling system with 7.5 quarts of Hyundai/Kia Long Life Coolant mixed to specification. Check transmission fluid level and top off with Kia SP-IV-M ATF if needed. Reconnect battery negative cable. Perform visual inspection for any disconnected hoses or wiring. Turn ignition to ON position without starting to prime fuel system (cycle 3-4 times). Start engine and immediately check for leaks (oil, coolant, fuel). Monitor oil pressure gauge/light. Allow engine to reach operating temperature while monitoring for abnormal noises or warning lights.

Reassembly

1. Reinstall hood aligning to marks made during removal
2. Reinstall engine under covers and splash shields
3. Have AC system recharged by qualified technician
4. Perform complete fluid level check of all systems
5. Reset engine computer by disconnecting battery for 15 minutes after initial startup verification

Verification

• Check for any fluid leaks around oil pan, valve cover, timing cover, and all gasket surfaces after initial startup
• Verify all warning lights extinguish after startup (check engine, oil pressure, coolant temperature)
• Test drive vehicle and verify normal operation, smooth acceleration, and no abnormal noises or vibrations
• Recheck all fluid levels after test drive and top off as necessary
• Verify proper engine temperature operation and cooling fan engagement
• Scan for diagnostic trouble codes using OBD-II scanner to ensure no sensor or system faults
• Perform final torque verification on all critical fasteners (engine mounts, transmission bolts) after engine reaches operating temperature

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