Complete replacement of all hydraulic valve lifters (tappets) on the 1.8L Nu engine, requiring cylinder head disassembly and camshaft removal.

Warnings

Tools required

Parts

• Hydraulic valve lifters (16 pieces) × 16 — Use OEM specification
• Valve cover gasket × 1 — Use OEM specification
• Valve cover PCV gasket × 1 — Use OEM specification
• Camshaft bearing cap bolts (if worn) × 10 — Use OEM specification
• Timing chain guide (inspect and replace if worn) × 1 — Use OEM specification
• Engine oil and filter × 1 — Use OEM specification
• RTV gasket sealant × 1 — Kia genuine or equivalent

Fluids

• Kia Genuine 5W-20 Engine Oil — 4.5 qt

Preparation

1. Park vehicle on level surface and engage parking brake. Allow engine to cool completely (minimum 2 hours).
2. Disconnect negative battery cable and secure away from terminal.
3. Remove engine cover and air intake system from throttle body to air filter housing.
4. Drain engine oil completely and remove oil filter.
5. Support engine from above using engine support fixture or hoist to relieve weight from mounts.
6. Remove right-side engine mount to provide access to timing chain cover.
7. Prepare clean workspace with organized parts trays. Label each tray for lifter position identification.
8. Have all replacement parts, gaskets, and RTV sealant ready before beginning disassembly.

Procedure

1. 1

   Remove valve cover and ignition coils
   Disconnect ignition coil connectors and remove all four ignition coils. Label coil positions. Disconnect PCV hose and breather hoses from valve cover. Remove valve cover bolts in reverse sequence (outside to inside pattern). Carefully lift valve cover and gasket. Inspect valve train for visible damage or wear patterns.
   Torque spec

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

   Set engine to TDC cylinder #1
   Remove spark plug from cylinder #1. Rotate crankshaft clockwise using 22mm socket on crankshaft pulley bolt until cylinder #1 is at top dead center on compression stroke (use finger over spark plug hole to feel compression). Align timing marks on camshaft sprockets - both cam lobes for cylinder #1 should point outward. Verify crankshaft keyway points upward. Mark timing chain to sprocket relationship with paint marker.
   ⚠️Confirm compression stroke by feeling air pressure at spark plug hole. If on exhaust stroke, rotate 360° more. Incorrect positioning will cause valve damage.
3. 3

   Remove timing chain cover and components
   Remove crankshaft pulley bolt (requires holding crankshaft). Remove timing chain cover bolts in sequence. Carefully remove timing chain cover - may require light tapping. Remove timing chain tensioner by compressing plunger and inserting retaining pin. Remove timing chain guides. Carefully remove timing chain from camshaft sprockets while maintaining alignment marks.
   ⚠Do NOT rotate crankshaft or camshafts once timing chain is removed. Use zip ties or wire to secure timing chain to prevent dropping into oil pan.
   Torque spec

   Cover Bolts15 Nm (11 lb-ft)
4. 4

   Remove camshaft position sensors
   Disconnect electrical connectors from intake and exhaust camshaft position sensors (located at rear of cylinder head). Remove mounting bolts and carefully extract sensors. Inspect O-rings for damage.
   Torque spec

   Camshaft Position Sensor10 Nm (7 lb-ft)
5. 5

   Remove camshaft bearing caps and camshafts
   Using permanent marker, clearly mark each camshaft bearing cap with position number and orientation arrow. Loosen camshaft bearing cap bolts in reverse sequence (outside to inside, alternating side-to-side) in 2-3 passes to gradually release valve spring pressure. Remove all bearing cap bolts and caps, keeping them in exact order. Carefully lift intake camshaft straight up. Repeat for exhaust camshaft. Place camshafts on clean surface with lobes protected.
   ⚠️Bearing caps MUST be loosened gradually in sequence to prevent camshaft warping or cap breakage from valve spring pressure. Sudden release can cause personal injury.
   ⚠Each bearing cap is machined as matched set with head. Never interchange caps between positions or engines.
   Torque spec

   Camshaft Bearing Cap Bolts14 Nm (10 lb-ft)
6. 6

   Remove rocker arms
   Remove rocker arm shaft bolts in reverse of tightening sequence. Lift rocker arm shaft assemblies straight up. Keep intake and exhaust rocker assemblies separate and identified. Inspect rocker arm contact surfaces for scoring or wear. Check rocker arm shaft for wear or damage.
   Torque spec

   Rocker Arm Shaft Bolts25 Nm (18 lb-ft)
7. 7

   Remove and inspect lifters
   Using magnetic pickup tool, carefully extract each lifter straight up from its bore. Immediately label and place each lifter in parts tray matching its cylinder and valve position (16 total: cylinders 1-4, intake/exhaust, front/rear). Inspect each lifter bore for scoring, deposits, or damage. Inspect lifter contact surfaces - any pitting, scoring, or flat spots requires replacement. Clean all lifter bores thoroughly with lint-free cloth and brake cleaner.
   ⚠Lifters wear to specific cam lobe patterns. If reusing any lifters, they MUST return to exact original positions. Any contamination in bores will cause immediate failure.
8. 8

   Prepare and install new lifters
   Remove new lifters from packaging in clean environment. Prime each new lifter by submerging in fresh engine oil and pumping plunger 10-15 times until resistance is felt. Coat lifter body with fresh engine oil. Verify each lifter bore is perfectly clean. Install each lifter straight down into its bore - should slide freely without force. Ensure lifters are fully seated at bottom of bores.
   ⚠New lifters must be primed with oil to prevent collapse and potential valve damage on first startup. Any binding during installation indicates contamination - remove and clean bore again.
9. 9

   Reinstall rocker arms
   Lubricate rocker arm shafts and rocker arm contact surfaces with fresh engine oil. Install rocker arm shaft assemblies, ensuring correct intake/exhaust positioning and shaft oil hole orientation (holes face downward). Install rocker arm shaft bolts finger-tight. Verify all rocker arms move freely. Tighten rocker arm shaft bolts evenly in sequence from center outward in 3 passes to final torque specification.
   ⚠Rocker arm shafts have oil passages that must be correctly oriented. Verify shaft notches or marks align per service manual orientation.
   Torque spec

   Rocker Arm Shaft Bolts25 Nm (18 lb-ft)
10. 10

    Reinstall camshafts
    Generously lubricate all camshaft bearing journals and cam lobes with fresh engine oil. Lubricate lifter contact surfaces. Carefully position exhaust camshaft into front bearing saddles with lobes for cylinder #1 pointing outward per TDC marks. Install intake camshaft similarly in rear position. Verify camshaft timing marks align with original TDC position. Apply light oil to bearing cap mating surfaces.
    ⚠️Camshafts must be installed in correct positions (intake vs exhaust) and correct rotational alignment. Verify timing marks before proceeding.
11. 11

    Install camshaft bearing caps
    Install each bearing cap in its exact original position with orientation marks facing forward (toward timing chain). Install all cap bolts finger-tight first. Verify caps are seated properly with no gaps. Tighten all bearing cap bolts in sequence (center caps first, then alternating outward) in 3 progressive passes: Pass 1 to 5 Nm, Pass 2 to 10 Nm, Pass 3 to final 14 Nm torque. Verify camshafts rotate smoothly by hand after torquing.
    ⚠️CRITICAL: Bearing cap bolts MUST be tightened in proper sequence in multiple passes. Single-pass tightening or wrong sequence will warp camshafts and destroy bearings, causing immediate engine failure.
    Torque spec

    Camshaft Bearing Cap Bolts14 Nm (10 lb-ft)
12. 12

    Reinstall timing chain and components
    Verify camshafts are still at TDC position with timing marks aligned. Route timing chain over crankshaft sprocket and up to camshaft sprockets. Align timing chain marks to camshaft sprocket marks exactly as marked during disassembly. Install timing chain guides. Install timing chain tensioner with plunger compressed and pin inserted. Remove tensioner pin to apply tension. Rotate crankshaft two complete revolutions clockwise and verify timing marks realign perfectly at TDC.
    ⚠️Timing chain alignment is CRITICAL. Even one tooth off will cause valve-to-piston contact and catastrophic engine damage. Verify marks align perfectly before proceeding.
13. 13

    Reinstall timing chain cover
    Clean all gasket surfaces on cylinder head and timing chain cover thoroughly with razor blade scraper. Apply thin bead of RTV silicone to timing chain cover mating surface per service manual pattern. Install new timing chain cover gasket. Position timing chain cover and install bolts finger-tight. Tighten cover bolts in sequence to specification. Allow RTV to cure per manufacturer instructions (typically 1 hour before adding oil).
    Torque spec

    Cover Bolts15 Nm (11 lb-ft)
14. 14

    Reinstall camshaft position sensors and valve cover
    Install new O-rings on camshaft position sensors lubricated with oil. Install sensors and tighten bolts to specification. Clean valve cover and cylinder head mating surfaces completely. Install new valve cover gasket and PCV valve gasket. Apply small dabs of RTV at front corners where timing cover meets cylinder head. Position valve cover and install bolts finger-tight. Tighten valve cover bolts in sequence (center outward pattern) to specification.
    Torque spec

    Camshaft Position Sensor10 Nm (7 lb-ft)

    Cover Bolts15 Nm (11 lb-ft)
15. 15

    Complete reassembly and prepare for startup
    Reinstall ignition coils in correct positions and connect electrical connectors. Reinstall spark plugs. Reinstall right-side engine mount and tighten mounting bolts to specification. Remove engine support fixture. Reinstall air intake system. Install new oil filter and fill engine with correct quantity of fresh 5W-20 oil (4.5 quarts). Reconnect battery negative cable.
    Torque spec

    Mounting Bolts45 Nm (33 lb-ft)

Reassembly

1. Do not start engine until RTV sealant has cured completely (minimum 1 hour, preferably 24 hours).
2. Before first start, turn ignition to ON position (without starting) for 5 seconds to prime fuel system. Repeat 3 times.
3. On first startup, lifters may be noisy for 30-60 seconds while they pump up with oil pressure. This is normal.
4. If lifter noise persists beyond 2 minutes of running, immediately shut down and investigate for installation errors.
5. After initial startup and warm-up, shut down and inspect for any oil leaks around valve cover and timing chain cover.

Verification

• Start engine and listen for abnormal valve train noise. Some initial ticking from lifters is normal for first 30-60 seconds.
• Allow engine to reach operating temperature while monitoring for leaks, unusual noises, or warning lights.
• Check engine oil level after running - top off if necessary to full mark on dipstick.
• Perform test drive and verify smooth engine operation at all RPM ranges without valve train noise, misfires, or performance issues.
• After 50 miles of driving, recheck valve cover and timing chain cover for any oil seepage.
• Consider performing compression test or leak-down test to verify proper valve sealing and timing.
• Scan for any stored diagnostic trouble codes related to camshaft position sensors or timing.
• Monitor oil consumption over next 500 miles - excessive consumption may indicate lifter or valve guide problems.

More procedures for this vehicle