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Home › Nissan-Datsun › 2004 › Sentra SE-R › Repair and Diagnosis › Engine Mechanical › Engine Mechanical - Qr25DE › Cylinder Block › Disassembly and Assembly › Assembly

Disassembly and Assembly: Assembly

    CAUTION: Use approved safety glasses to protect your eyes.
  1. Using compressed air, clean out the coolant and oil passages in the cylinder block, the cylinder bore and the crankcase to remove any foreign material.
  2. Install the drain plugs on the cylinder block.
    Fig 1: Installing Drain Plugs On Cylinder Block
    G02007917Courtesy of NISSAN MOTOR CO., U.S.A.
  3. Install the main bearings and the thrust bearings.
    Fig 2: Identifying Main & Thrust Bearings
    G02007918Courtesy of NISSAN MOTOR CO., U.S.A.
    1. Remove dust, dirt, and oil from the bearing mating surfaces of the cylinder block and lower cylinder block.
    2. Install the thrust bearings to both sides of the No. 3 main bearing journal on the cylinder block.
      • Install the thrust bearings with the oil groove facing the crankshaft arm (outside).
    3. Install the main bearings paying attention to their position and direction.
      Fig 3: Identifying Main Bearing Positions & Directions
      G02007919Courtesy of NISSAN MOTOR CO., U.S.A.
      • The main bearing with an oil hole and groove goes on the cylinder block. The one without them goes on the lower cylinder block.
      • Only the main bearing (on the cylinder block) for No. 3 journal has different specifications.
      • Before installing the bearings, apply engine oil to the bearing friction surface (inside). Do not apply oil to the back surface, but thoroughly clean it.
      • When installing, align the bearing stopper to the notch.
      • Make sure that the oil holes on the cylinder block and those on the corresponding bearing are aligned.
  4. Install the signal plate to the crankshaft.
    Fig 4: Installing Signal Plate
    G02007920Courtesy of NISSAN MOTOR CO., U.S.A.

    Signal plate bolts: 12 - 14 N.m (1.22 - 1.43 kg.m, 9 - 10 ft.lb) 

    1. Position the crankshaft and signal plate using a positioning dowel pin, and tighten the mounting bolts to specification.
      2. CAUTION: Be sure to remove dowel pin before installing the crankshaft.
      Dowel pins for the crankshaft and signal plate are supplied as a set for each.
    2. Remove the dowel pin.
  5. Install the crankshaft onto the cylinder block.
    • While turning the crankshaft by hand, check that it turns smoothly.
    6. NOTE: Cylinder block and lower cylinder block are machined together.
    Neither of them can be replaced separately.
  6. Install the lower cylinder block.
      CAUTION: After the RTV Silicone Sealant is applied, the lower cylinder block installation must be finished within 5 minutes.
      Fig 5: Identifying RTV Silicone Sealant Locations
      G02007921Courtesy of NISSAN MOTOR CO., U.S.A.
    • Apply RTV Silicone Sealant to positions shown in Fig 5.
  7. Tighten lower cylinder block mounting bolts in the numerical order shown in Fig 6 and according to the following steps:
    Fig 6: Lower Cylinder Block Mounting Bolt Tightening Sequence
    G02007922Courtesy of NISSAN MOTOR CO., U.S.A.
    1. Apply new engine oil to threads and seat surfaces of the mounting bolts.
    2. Tighten bolts No. 1 - 10 only in the order shown, to specification below.

      First tightening, bolts 1 - 10 only: 36.3 - 42.2 N.m (3.7 - 4.3 kg.m, 27 - 31 ft.lb) 

      3. CAUTION: Use an angle wrench (special service tool) or protractor to check judgment by visual inspection.
    3. Tighten bolts No. 1 - 10 only in the order shown in Fig 6, to specification below.

      Second tightening, bolts 1 - 10 only: 60-65° rotation (target: 60°) 

    4. Tighten bolts No. 11 - 22 only in the order shown in Fig 6, to specification below.
      Fig 7: Using Angle Wrench
      G02007923Courtesy of NISSAN MOTOR CO., U.S.A.

      Third tightening, bolts 11 - 22 only: 19.6 - 24.5 N.m (2.0 - 2.5 kg.m, 15 - 18 ft.lb) 

      • Wipe off completely any protruding RTV Silicone Sealant on the exterior of engine.
      • Check crankshaft side clearance. Refer to CRANKSHAFT SIDE CLEARANCE .
      • After installing the mounting bolts, make sure that the crankshaft can be rotated smoothly by hand.
  8. Install the rear oil seal.
    Fig 8: Installing Rear Oil Seal With Seal Driver
    G02007924Courtesy of NISSAN MOTOR CO., U.S.A.
    • Press the oil seal between cylinder block and crankshaft with a suitable drift.
    • Be careful not to touch the grease on the oil seal lip.
    • Be careful not to cause scratches or burrs when pressing in the rear oil seal.
    • Press in rear oil seal to the position shown in Fig 9.
      Fig 9: Rear Oil Seal Installation Depth
      G02007925Courtesy of NISSAN MOTOR CO., U.S.A.
  9. Install the piston to the connecting rod. Assemble the components in their original positions.
    1. Using a snap ring pliers, install the snap ring into the grooves of the piston's rear side.
      • Insert the piston pin snap ring fully into groove.
    2. Install the piston to the connecting rod.
      • Using a heat gun, heat the piston [approximately 60-70°C (140-158°F)] until the piston pin can be pushed in by hand without excessive force. From the front to the rear, insert the piston pin into the piston and the connecting rod.
      • Assemble so that the front mark on the piston crown and the oil holes and the cylinder No. on the connecting rod are positioned as shown in Fig 10.
        Fig 10: Installing Connecting Rod To Piston
        G02007926Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Install the piston pin snap ring into the front of the piston.
      • Check that the connecting rod moves smoothly.
    10. CAUTION: Be careful not to damage the piston.
  10. Using a piston ring expander, install the piston rings. Assemble the components in their original positions.
    • Position each ring with the gap as shown in Fig 11, referencing the piston front mark as the starting point.
      Fig 11: Positioning Piston Ring Gaps
      G02007927Courtesy of NISSAN MOTOR CO., U.S.A.
    • Install the top ring and the second ring with the stamped surface facing upward.

      Stamped mark: A (top ring) 

      :2A (second ring) 

  11. Install the connecting rod bearings to the connecting rod and the connecting rod cap. Assemble the components in their original positions.
    Fig 12: Assembly Order Of Connecting Rods, Bearings & Caps
    G02007928Courtesy of NISSAN MOTOR CO., U.S.A.
    • When installing the connecting rod bearings, apply engine oil to the bearing friction surface (inside). Do not apply oil to the back surface, but thoroughly clean the back.
    • When installing, align the connecting rod bearing stopper protrusion with the notch of the connecting rod to install.
    • Check the oil holes on the connecting rod and those on the corresponding bearing are aligned.
  12. Install the piston and connecting rod assembly to the crankshaft. Assemble the components in their original positions.
    Fig 13: Installing Piston & Connecting Rod Assembly
    G02007929Courtesy of NISSAN MOTOR CO., U.S.A.
    • Rotate the crankshaft so the pin corresponding to the connecting rod to be installed is at the bottom dead center position.
    • Apply engine oil sufficiently to the cylinder bore, piston, and crankshaft pin.
    • Match the cylinder position number with the cylinder No. on the connecting rod for installation.
      • CAUTION: Be careful not to damage the crankshaft pin, resulting from an interference of the connecting rod big end.
    • Using a piston ring compressor, install the piston with the front mark on the piston crown facing the front of the engine.
  13. Install the connecting rod caps. Assemble the components in their original positions.
    • Match the stamped cylinder number marks on the connecting rod with those on the cap to install.
      Fig 14: Locating Connecting Rod Cap Stamped Numbers
      G02007930Courtesy of NISSAN MOTOR CO., U.S.A.
    14. CAUTION: Always use either an angle wrench or protractor. Avoid tightening based on visual check alone.
    Fig 15: Tightening Connecting Rod Bolt
    G02007931Courtesy of NISSAN MOTOR CO., U.S.A.
  14. Tighten the connecting rod bolt as follows:

    Apply engine oil to the threads and seats of the connecting rod bolts.

    Stage 1: 18.6 - 20.6 N.m (1.9 - 2.1 kg.m, 14 - 15 ft.lb) 

    Stage 2: Rotate bolts 85-95° (target 90°) 

    • Check the connecting rod side clearance. Refer to CONNECTING ROD SIDE CLEARANCE .
    • After tightening the bolts, make sure that the crankshaft rotates smoothly.
  15. Install flywheel (M/T Models), or drive plate (A/T Models).
    • Install drive plate, reinforcement plate and pilot converter as shown in Fig 16.
      Fig 16: Installing Drive Plate, Reinforcement Plate & Pilot Converter
      G02007932Courtesy of NISSAN MOTOR CO., U.S.A.
    • Using a drift with 33 mm (1.30 in) diameter, push pilot converter into the end of the crankshaft.
    16. CAUTION: If the knock sensor is dropped, replace it with new one.
  16. Install the knock sensor.
    • Make sure that there is no foreign material on the cylinder block mating surface and the back surface of the knock sensor.
    • Install the knock sensor with the connector facing lower left by 45° as shown in Fig 17.
      Fig 17: Installing Knock Sensor
      G02007933Courtesy of NISSAN MOTOR CO., U.S.A.
    • Do not tighten the mounting bolts while holding the connector.
    • Make sure that the knock sensor does not interfere with other parts.

      Knock sensor bolt: 15.7 - 26.5 N.m (1.6 - 2.7 kg.m, 12 - 19 ft.lb) 

  17. Install the crankshaft position sensor (POS).

    Crankshaft Position (CKP) sensor bolt: 5.4 - 7.3 N.m (0.55 - 0.75 kg.m, 48 - 65 in.lb) 

  18. Remaining installation is in the reverse order of removal.
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