Connecting Rod Bearings

Complete replacement of connecting rod bearings on the 3.0L V6 Twin Turbo engine, requiring removal of engine oil pan, crankshaft access, and precise bearing installation with torque-to-yield fasteners.

Warnings

Tools required

Parts

• Connecting rod bearing set (standard or oversized as measured) × 1 — Use OEM specification
• Connecting rod bolts (TTY - must replace) × 12 — Use OEM specification
• Oil pan gasket × 1 — Use OEM specification
• Oil drain plug crush washer × 1 — Use OEM specification
• Engine oil filter × 1 — Use OEM specification
• RTV silicone gasket maker (Maserati approved) × 1 — Use OEM specification
• Lower crankcase gasket/seal × 1 — Use OEM specification
• Coolant hose clamps (as needed) × 6 — Use OEM specification
• Various O-rings and seals × 1 — Use OEM specification

Fluids

• Selenia Racing 10W-60 — 5.5 qt
• Maserati OAT Coolant — 10 qt

Preparation

1. Ensure vehicle is on level ground with parking brake engaged and front wheels chocked
2. Disconnect negative battery terminal and wait 15 minutes for system discharge
3. Drain engine oil completely and remove oil filter, allowing 30 minutes for full drainage
4. Drain cooling system from radiator petcock and lower hose into appropriate container
5. Remove engine cover and upper intake plenum for access
6. Remove both turbochargers and associated piping (mark all connections)
7. Photograph all electrical connections, vacuum lines, and hose routing for reassembly reference
8. Support engine with hoist from above using appropriate lifting brackets
9. Remove front subframe mounting bolts and lower subframe for clearance (if not removing engine)
10. Create a clean workspace with dedicated clean assembly area for bearing work

Procedure

1. 1

   Remove oil pan and inspect damage
   Remove all oil pan bolts in reverse sequence (outside to inside pattern). Carefully separate oil pan from block using plastic wedges, not pry bars. Inspect oil pan for metal debris and contamination. Examine oil pickup screen for blockage or damage. If metal particles are present, investigate root cause before proceeding.
   Torque spec

   Oil Pan Bolts12 Nm (9 lb-ft)
2. 2

   Remove windage tray and oil pump pickup
   Remove windage tray mounting bolts and carefully lift tray clear of crankshaft. Remove oil pump pickup tube mounting bolts and extract pickup assembly. Inspect pickup screen mesh for debris. Clean all components thoroughly with brake cleaner.
   Torque spec

   Mounting Bolts50 Nm (37 lb-ft)
3. 3

   Rotate crankshaft and mark connecting rods
   Using crankshaft rotation tool at front pulley bolt, rotate engine to position cylinder 1 at bottom dead center (BDC). Use permanent marker or engraving tool to mark each connecting rod cap with cylinder number (1-6) and orientation arrow pointing toward front of engine. Mark corresponding rod body to match. Verify all rods are uniquely identified before removing any caps.
4. 4

   Remove connecting rod caps systematically
   Starting with cylinder 1, remove both connecting rod bolts. Carefully lift rod cap straight off, keeping bearing shell with cap if bearing will be inspected. Place cap with bearing in labeled container or bag marked with cylinder number. Repeat for all six cylinders, rotating crankshaft as needed to access each rod at BDC. Keep all components organized by cylinder number.
   ⚠Rod caps must be kept with their original rod. Swapping caps between rods will cause bearing failure due to slight manufacturing differences.
   Torque spec

   Connecting Rod Bolts45 Nm (33 lb-ft)
5. 5

   Push pistons up and remove rod bearings
   With rod cap removed, gently push piston and rod assembly upward into cylinder bore using wooden dowel or plastic hammer handle (never metal). Push only far enough to access bearing. Remove upper bearing shell from connecting rod. Inspect bearing surface for scoring, excessive wear, or embedded material. Photograph bearing condition for each cylinder. Lower piston back to BDC. Repeat for all cylinders.
6. 6

   Inspect and measure crankshaft journals
   Clean all six connecting rod journals on crankshaft with lint-free cloth and brake cleaner. Inspect for scoring, discoloration, or visible damage. Using micrometer, measure each journal diameter at multiple points (front, center, rear) and orientations (vertical, horizontal, 45-degree). Record all measurements. Compare to factory specification (typically 52.00-52.02mm). Out-of-round or taper exceeding 0.01mm requires crankshaft machining or replacement.
   ⚠If any journal is scored or measures undersize, crankshaft must be machined and undersize bearings used, or crankshaft replaced.
7. 7

   Measure connecting rod bore diameter
   Using dial bore gauge, measure inside diameter of each connecting rod big end bore (with cap installed and torqued to specification using OLD bolts for measurement only). Measure at multiple orientations. Record measurements. Calculate bearing clearance by subtracting crankshaft journal diameter from rod bore diameter and subtracting twice the bearing shell thickness (typically specified as 0.025-0.070mm total clearance).
   ℹ️This is a preliminary calculation. Final clearance MUST be verified with Plastigage during assembly.
8. 8

   Clean all bearing surfaces thoroughly
   Remove all traces of old bearing material, oil, and debris from connecting rod bearing bores and caps using lint-free cloths and brake cleaner. Clean crankshaft journals again. Ensure oil passages in rods and crankshaft are clear by spraying brake cleaner through them. Allow all components to air dry completely. Inspect surfaces under good lighting for any remaining contamination. This is critical for bearing survival.
9. 9

   Install new bearing shells (dry fit)
   Install new upper bearing shell into connecting rod by aligning locating tab with notch in rod. Ensure bearing snaps into place and seats fully with no gaps. Install lower bearing shell into rod cap the same way. DO NOT lubricate bearings yet. Verify bearing edge does not protrude beyond rod parting surface (slight crush is normal, 0.025-0.050mm). Repeat for all rods and caps.
10. 10

    Check bearing clearance with Plastigage
    Place strip of Plastigage lengthwise on crankshaft journal (do not rotate crank with Plastigage installed). Push piston and rod assembly down onto journal ensuring bearing seats fully on crank. Install rod cap in correct orientation with NEW connecting rod bolts. Torque bolts to 45 Nm ONLY (do not add angle yet). Do not rotate crankshaft. Carefully remove rod cap without disturbing Plastigage. Measure flattened Plastigage width using scale on package. Compare to specification (0.025-0.070mm typical). Record clearance for each rod. If clearance is incorrect, determine if bearing size or crankshaft issue.
    ⚠️Clearance outside specification will cause bearing failure. Do not proceed until correct clearance is achieved with proper bearing size.
    Torque spec

    Connecting Rod Bolts45 Nm (33 lb-ft)
11. 11

    Remove Plastigage and prepare for final assembly
    Remove rod caps and clean all Plastigage residue from bearings and crankshaft journals using clean cloth. Wipe all surfaces clean with lint-free cloth. Apply thin coat of assembly lubricant or Selenia Racing 10W-60 oil to all bearing surfaces, both upper and lower shells. Coat crankshaft journals with oil. Ensure oil passages are clear.
12. 12

    Final connecting rod installation and torque
    Push each piston and rod assembly down onto its corresponding crankshaft journal ensuring bearing seats fully. Install rod cap in correct orientation (match marks and cylinder numbers). Install NEW connecting rod bolts and hand tighten. Using calibrated torque wrench, torque bolts to 45 Nm in smooth motion. Immediately following torque, mark bolt head position and tighten additional angle per factory specification (typically 90-100 degrees). Use angle gauge to verify precise angle. Repeat for all six connecting rods. Verify crankshaft rotates smoothly by hand after each rod is installed.
    ⚠️NEW bolts MUST be used. TTY bolts stretch during torque-angle tightening and cannot be reused. Using old bolts will result in bolt failure and catastrophic engine damage.
    ⚠If crankshaft does not rotate smoothly after installing a rod, bearing clearance is too tight. Remove cap and investigate immediately.
    Torque spec

    Connecting Rod Bolts45 Nm (33 lb-ft)
13. 13

    Install oil pump pickup and windage tray
    Position oil pump pickup tube with new O-ring and install mounting bolts. Torque to specification. Position windage tray over crankshaft and align all mounting holes. Install mounting bolts and torque in sequence from center outward. Verify windage tray does not contact crankshaft counterweights by rotating crank through full revolution.
    Torque spec

    Mounting Bolts50 Nm (37 lb-ft)
14. 14

    Prepare and install oil pan
    Clean oil pan and engine block mating surfaces completely using gasket scraper and brake cleaner. Surfaces must be completely free of old gasket material and RTV. Apply thin bead of RTV silicone to block gasket surface if specified, or install new oil pan gasket per manufacturer instructions. Position oil pan carefully and install all bolts hand tight. Torque oil pan bolts in proper sequence (center outward, alternating pattern) to 12 Nm. Allow RTV to cure per product specifications before adding oil.
    ℹ️Some Maserati engines require specific RTV application pattern. Consult factory procedure for exact RTV bead placement to avoid blocking oil passages.
    Torque spec

    Oil Pan Bolts12 Nm (9 lb-ft)
15. 15

    Reinstall subframe and engine accessories
    Raise front subframe into position and install mounting bolts. Torque subframe bolts to specification in proper sequence. Reinstall turbochargers with new gaskets and torque mounting fasteners per specification. Reconnect all coolant hoses with new clamps. Reinstall intake plenum and all vacuum connections per photographs. Reconnect all electrical connectors. Install new oil drain plug crush washer and install drain plug, torquing to 35 Nm. Install new oil filter.
    Torque spec

    Oil Drain Plug35 Nm (26 lb-ft)

    Mounting Bolts50 Nm (37 lb-ft)

Reassembly

1. Refill engine with 5.5 quarts Selenia Racing 10W-60 oil through oil filler cap
2. Refill cooling system with 10 quarts Maserati OAT coolant and bleed air from system per factory procedure
3. Reconnect negative battery terminal and allow all systems to initialize
4. Prime oil system by cranking engine with fuel system disabled (pull fuel pump relay) for 10 seconds, wait 30 seconds, repeat 3 times until oil pressure is observed
5. Reinstall fuel pump relay and start engine, monitoring oil pressure immediately

Verification

• Oil pressure should register within 3 seconds of startup and reach minimum 28 psi (2 bar) at idle when warm
• Listen for any abnormal bearing noise (knocking or ticking) at idle and under light throttle - any noise indicates bearing problem
• Monitor oil pressure continuously during first 30 minutes of operation across idle and varying RPM
• Check for oil leaks around oil pan gasket and drain plug after 15 minutes of operation
• After first 20 miles of driving, re-check oil level and inspect for leaks
• Monitor engine for first 500 miles with frequent oil level checks and listen for any developing noises
• Consider oil analysis after first 500 miles to verify bearing material is not present in oil
• Verify coolant level is stable with no leaks from disturbed connections

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