Connecting Rod Bearings

This procedure covers the replacement of connecting rod bearings on the 2016-2021 Honda Civic 1.5L turbo engine, requiring complete engine removal and disassembly of the lower end.

Warnings

Tools required

Parts

• Connecting rod bearing set (standard or oversized) × 1 — Use OEM specification
• Connecting rod bolts × 8 — Use OEM specification - replace if stretched
• Engine oil and filter × 1 — Use OEM specification
• Oil pan gasket × 1 — Use OEM specification
• Timing chain and guides (inspect/replace) × 1 — Use OEM specification
• Main seal set × 1 — Use OEM specification
• Head gasket set × 1 — Use OEM specification
• Coolant × 1 — Honda Type 2 Blue
• Valve cover gasket × 1 — Use OEM specification

Fluids

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

Preparation

1. Park vehicle on level surface and engage parking brake
2. Disconnect negative battery terminal and wait 3 minutes for airbag system to discharge
3. Drain engine oil completely and remove oil filter
4. Drain cooling system completely from radiator petcock and engine block drain
5. Remove engine cover and air intake system
6. Relieve fuel system pressure by removing fuel pump fuse and cranking engine until it stalls
7. Label and photograph all electrical connectors, vacuum lines, and hose routing before disconnection
8. Support vehicle on jack stands at all four corners with sufficient clearance for engine removal from below
9. Remove front wheels and splash shields for access to subframe
10. Document cylinder compression readings before disassembly for comparison

Procedure

1. 1

   Remove engine from vehicle
   Disconnect all electrical connectors, fuel lines, coolant hoses, and vacuum lines from engine. Remove turbocharger heat shields and intercooler piping. Disconnect exhaust system at turbo flange. Remove drive axles from transmission. Support transmission with jack and remove engine mount bolts. Attach engine hoist and carefully lift engine forward and upward out of engine bay. Transfer engine to engine stand and secure with mounting bolts.
   Torque spec

   Mounting Bolts45 Nm (33 lb-ft)
2. 2

   Remove external engine components
   Remove alternator, starter, turbocharger assembly, exhaust manifold, intake manifold, fuel rail and injectors, water pump, thermostat housing, and all accessory brackets. Remove timing chain cover by removing all cover bolts. Label and store all hardware separately by component.
   Torque spec

   Cover Bolts15 Nm (11 lb-ft)
3. 3

   Remove timing chain and valve train
   Rotate crankshaft to TDC on cylinder #1. Mark timing chain relationship to cam and crank sprockets. Remove timing chain tensioner and guides. Remove timing chain. Remove cylinder head bolts in reverse of tightening sequence and lift cylinder head off block. Inspect head gasket condition and cylinder head surface for warping.
   Torque spec

   Gasket Bolts19 Nm (14 lb-ft)
4. 4

   Remove oil pan and oil pickup
   With engine inverted on stand, remove all oil pan bolts and carefully separate oil pan from block using plastic wedges. Remove oil pickup tube and screen assembly. Remove windage tray or baffle if equipped. Clean all old gasket material from mating surfaces.
5. 5

   Inspect and measure cylinder bores
   Use cylinder ridge reamer to remove any ridge at top of cylinder bores. Measure each cylinder bore at three heights (top, middle, bottom) in two perpendicular directions using dial bore gauge or telescoping gauge with micrometer. Record measurements. Maximum allowable taper is 0.002 inches and out-of-round is 0.001 inches. If exceeded, block requires machining.
6. 6

   Mark and remove connecting rod assemblies
   Mark each connecting rod cap and rod body with corresponding cylinder number (1-4) using permanent marker or number stamps on non-bearing surfaces. Mark orientation (front of engine). Remove connecting rod bolts from each rod cap. Carefully separate cap from rod and push piston/rod assembly up and out through top of cylinder. Place rod cap back on rod with bearings installed to keep sets together. Arrange assemblies in order on clean workspace.
7. 7

   Inspect crankshaft journals and components
   Inspect all connecting rod journals on crankshaft for scoring, discoloration, or damage. Measure journal diameter and out-of-round with micrometer at multiple points. Standard journal diameter is 48.016-48.024mm. Maximum allowable taper is 0.010mm. Inspect connecting rods for bending, twisting, or cracks using magnetic particle inspection if available. Check connecting rod side clearance specification.
8. 8

   Select and verify bearing clearances
   Clean all bearing surfaces on connecting rods and caps thoroughly with solvent. Install new bearing shells in rods and caps, ensuring bearing tabs are properly seated in notches. Place Plastigage strip on each crankshaft journal parallel to crankshaft axis. Install piston/rod assembly back in cylinder and install rod cap with bearings in correct orientation. Torque connecting rod bolts to 20 Nm then rotate 90 degrees. Remove cap and measure Plastigage width using scale on package. Proper clearance is 0.025-0.050mm. If outside specification, select different bearing size (oversized if journal is undersize).
   Torque spec

   Connecting Rod Bolts20 Nm (15 lb-ft) + 90°
9. 9

   Clean and prepare all components
   Remove Plastigage residue completely from all bearing surfaces with clean solvent. Clean all connecting rod and cap bearing bores thoroughly. Clean crankshaft journals with lint-free cloth. Clean piston ring grooves and oil return holes. Oil all bearing surfaces with fresh engine oil before final assembly.
10. 10

    Install connecting rod bearings and pistons
    Install new bearing shells in connecting rods and caps with light coat of assembly lube or engine oil. Ensure bearing tabs are fully seated. Stagger piston ring end gaps 120 degrees apart with no gaps aligned with pin bore axis. Oil piston rings and cylinder walls thoroughly. Use ring compressor to compress rings and carefully tap piston into cylinder with wood or plastic hammer handle. Ensure piston orientation mark faces front of engine. Guide connecting rod onto crankshaft journal, being careful not to scratch journal.
11. 11

    Install connecting rod caps and torque bolts
    Install correct connecting rod cap on each rod in proper orientation matching marks made during disassembly. Install new connecting rod bolts (if reusing old bolts, verify they are within stretch specification). Lubricate bolt threads and underside of bolt heads with engine oil. Hand-tighten bolts, then torque to 20 Nm (15 lb-ft) in two stages. Finally, rotate each bolt an additional 90 degrees using angle gauge. Verify rod side clearance is within specification (0.15-0.35mm). After all rods are installed, rotate crankshaft by hand two complete revolutions to verify smooth rotation with no binding.
    Torque spec

    Connecting Rod Bolts20 Nm (15 lb-ft) + 90°
12. 12

    Reinstall oil system and pan
    Install oil pickup tube with new O-ring and torque sensor bolts to 10 Nm. Install windage tray if equipped. Apply thin bead of Honda Bond or RTV sealant to oil pan mating surface. Install new oil pan gasket and position oil pan onto block. Install oil pan gasket bolts and torque to 19 Nm in criss-cross pattern from center outward. Allow sealant to cure for 30 minutes before adding oil.
    Torque spec

    Sensor Bolts10 Nm (8 lb-ft)

    Gasket Bolts19 Nm (14 lb-ft)
13. 13

    Reinstall cylinder head and timing system
    Clean cylinder head and block mating surfaces thoroughly. Install new head gasket with TOP marking facing up. Carefully position cylinder head onto block, ensuring dowel pins align. Install new head bolts and torque in proper sequence per Honda specification. Install timing chain with marks aligned to TDC position. Install chain guides and tensioner. Install timing cover with new gasket and torque cover bolts to 15 Nm. Rotate engine two complete revolutions and verify timing marks realign at TDC.
    Torque spec

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

    Reinstall external components and engine
    Reinstall all external components in reverse order of removal: water pump, thermostat, intake and exhaust manifolds, turbocharger, fuel system, and all accessories. Torque all mounting bolts to specification (19 Nm for standard mounting bolts, 33 Nm for critical mounting bolts). Use engine hoist to carefully lower engine back into vehicle. Install engine mounts and torque to 45 Nm. Reconnect all drive axles, exhaust, electrical connectors, coolant hoses, and fuel lines.
    Torque spec

    Mounting Bolts45 Nm (33 lb-ft)
15. 15

    Fill fluids and perform initial startup
    Install new oil filter and fill engine with 4.0 quarts Honda Genuine 0W-20 oil. Fill cooling system with 6.0 quarts Honda Type 2 Blue coolant and bleed air from system. Reconnect battery. Prime fuel system by cycling ignition on/off three times without cranking. Start engine and verify oil pressure immediately. Allow engine to idle and monitor for leaks, unusual noises, or vibrations. Check for proper operation of all accessories. Allow engine to reach operating temperature and verify cooling system operation.

Reassembly

1. Replace all gaskets, seals, and torque-to-yield fasteners during reassembly
2. Use only Honda Genuine parts for bearings, bolts, and gaskets to ensure proper clearances and reliability
3. Liberally lubricate all bearing surfaces with engine oil or assembly lube during installation
4. Follow exact torque sequences and specifications to prevent warping or uneven clamping forces
5. Double-check timing chain alignment before finalizing timing cover installation

Verification

• Verify no oil leaks after initial startup and test drive
• Confirm oil pressure reading is within normal range (25-80 psi at operating temperature)
• Listen for abnormal engine noises such as knocking, ticking, or rattling that could indicate bearing issues
• Perform test drive and verify smooth acceleration with no hesitation or misfires
• Monitor coolant temperature to ensure proper cooling system operation
• Check engine oil level after first drive and inspect for metal particles or contamination
• Consider oil analysis after 500 miles to verify bearing wear is within normal range
• Verify no diagnostic trouble codes are present after repair completion

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