Nissan Armada 2025-2026 Service and Repair Manual: Disassembly and Assembly

DISASSEMBLY

Remove the following parts:

• Oil pan (lower): Refer to Removal and Installation.

• Oil pan (upper): Refer to Disassembly and Assembly.

• Timing chain: Refer to Removal and Installation.

• Cylinder head: Refer to Removal & Installation.

• Oil strainer and oil pump: Refer to Removal and Installation.

• Baffle plate

Remove knock sensor.

CAUTION:

Carefully handle sensor avoiding shocks.

Remove piston and connecting rod assembly with the following procedure:

• Before removing piston and connecting rod assembly, check the connecting rod side clearance. Refer to Inspection.

CAUTION:

Never drop connecting rod bearing, and to scratch the surface.

Position crankshaft pin corresponding to connecting rod to be removed onto the bottom dead center. Remove connecting rod bearing cap. Using a hammer handle or similar tool, push piston and connecting rod assembly out to the cylinder head side.

CAUTION:

Never damage the cylinder wall and crankshaft pin, resulting from an interference of the connecting rod big end.

Remove connecting rod bearings from connecting rod and connecting rod bearing cap.

CAUTION:

• Never drop connecting rod bearing, and to scratch the surface.

• Identify installation positions, and store them without mixing them up.

Remove piston rings from piston.

• Before removing piston rings, check the piston ring side clearance. Refer to Inspection.

• Use a piston ring expander (commercial service tool) (A).

  

CAUTION:

• When removing piston rings, be careful not to damage piston.

• Never damage piston rings by expanding them excessively.

Remove piston from connecting rod as follows: Using snap ring pliers (A), remove snap rings.

Heat piston to 60 to 70°C (140 to 158°F) with an industrial use dryer (A) or equivalent.

Push out piston pin using a stick than has an outer diameter of approximately 20 mm (0.79 in).

Remove lower cylinder block bolts.

• Before loosening lower cylinder block bolts, measure the crankshaft end play. Refer to Inspection.

• Loosen lower cylinder block bolts in the order from 26 to 1 shown in the figure in several different steps.

  

  : Engine front

Remove lower cylinder block as follows:

Screw M8 bolt [pitch: 1.25 mm (0.049 in) length: approximately 50 mm (1.97 in)] into bolt holes . Then equally tighten each bolt, and remove lower cylinder block.

: Engine front

CAUTION:

• Never damage the mounting surfaces.

• Never tighten bolts excessively.

• Never insert screwdriver, this will damage the mating surface.

Remove crankshaft.

Pull rear oil seal out from rear end of crankshaft.

Remove main bearings and thrust bearings from cylinder block and lower cylinder block.

CAUTION:

• Never drop main bearing, and to scratch the surface.

• Identify installation positions, and store them without mixing them up.

Remove oil jet.

ASSEMBLY

CAUTION:

Do not reuse O-rings or washers.

NOTE:

If a piston, connecting rod or crankshaft are removed, carry out teach of “Electric IVT Control Actuator Position Learning”. Refer to Work Procedure.

Fully air-blow engine coolant and engine oil passages in cylinder block, cylinder bore and crankcase to remove any foreign material.

CAUTION:

Use goggles to protect your eyes.

Install each plug to cylinder block as shown in the figure.

	: Plug
	: Engine front

• Apply sealant to the thread of water drain plug .

  CAUTION:

  Do not reuse washers.

• Apply sealant to the thread of plug.

  Use Genuine High Strength Locking Sealant or an equivalent. Refer to Recommended Chemical Products and Sealants.

• Replace washer with new one.

• Tighten each plug as specified below.

  Unit: N·m (kg-m, ft-lb)

  Part	Washer	Tightening torque
  	No	19.6 (2.0, 14)
  	Yes	78.0 (8.0, 58)

Install oil jet.

Install main bearings and thrust bearings as follows:

CAUTION:

Never drop main bearing, and to scratch the surface.

Remove dust, dirt, and engine oil on bearing mating surfaces of cylinder block and lower cylinder block. Install thrust bearings to both sides of the No. 3 journal housing on cylinder block.

	: No. 1
	: No. 2
	: No. 3
	: No. 4
	: Thrust bearing installation position
	: Engine front

• Install thrust bearings with the oil groove facing crankshaft arm (outside).

Install main bearings paying attention to the direction.

	: Cylinder block side
	: Lower cylinder block side
	: Engine front

• Main bearing with oil hole and groove goes on cylinder block. The one without them goes on lower cylinder block.

• Before installing main bearings, apply engine oil to the bearing surface (inside). Do not apply engine oil to the back surface, but thoroughly clean it.

• When installing, align main bearing stopper protrusion to cutout of cylinder block and lower cylinder block.

• Ensure the oil holes on cylinder block and those on the corresponding bearing are aligned.

Install crankshaft to cylinder block.

• While turning crankshaft by hand, check that it turns smoothly.

Install lower cylinder block.

CAUTION:

Do not reuse O-rings.

NOTE:

Lower cylinder block cannot be replaced as a single part, because it is machined together with cylinder block.

• Apply a continuous bead of liquid gasket with the tube presser (commercial service tool) to lower cylinder block as shown in the figure.

  

  : φ3.4 - 4.4 mm (0.134 - 0.173 in)

Inspect the outer diameter of lower cylinder block bolt. Refer to Inspection.

Install lower cylinder block bolts in numerical order as shown in the figure as follows:Apply new engine oil to threads and seat surfaces of lower cylinder block bolts. Tighten bolts (No. 17 to 26) in numerical order as shown in the figure.

: Engine front

: 25.1 N·m (2.6 kg-m, 19 ft-lb)

CAUTION:

Do not reuse O-rings.

Repeat step b. Tighten bolts (No. 1 to 16) in numerical order as shown in the figure.

: Engine front

NOTE:

Use TORX socket (commercial service tool) for bolts No.1 to 16.

: 44.2 N·m (4.5 kg-m, 33 ft-lb)

Turn bolts (No. 1 to 16) 90+5 degrees clockwise (angle tightening).

CAUTION:

Use the angle wrench [SST: KV10112100 (BT-8653-A)] (A) to check tightening angle. Never make judgment by visual inspection.

• After installing lower cylinder block bolts, check that crankshaft can be rotated smoothly by hand.

• Check the crankshaft end play. Refer to Inspection.

Install piston to connecting rod as follows: Using snap ring pliers, install new snap ring to the groove of piston rear side.

• Insert it fully into groove to install.

Install piston to connecting rod.

• Using an industrial use dryer or similar tool, heat piston until piston pin can be pushed in by hand without excess force [approximately 60 to 70°C (140 to 158°F)]. From the front to the rear, insert piston pin into piston and connecting rod.

• Assemble so that the front mark on the piston head and the cylinder number on connecting rod are positioned as shown in the figure.

  

  	: Two dimensional code
  	: Front mark
  	: Cylinder number
  	: Front mark
  	: Engine front

Install new snap ring to the groove of the piston front side.

• Insert it fully into groove to install.

• After installing, check that connecting rod moves smoothly.

Using a piston ring expander (commercial service tool) (A), install piston rings.

CAUTION:

• When installing piston rings, be careful not to damage piston.

• Never damage piston rings by expending them excessively.

• If there is stamped mark on ring, mount it with marked side up.

  

  Stamped mark:
  Top ring	: 1 N
  Second ring	: 2 N

• Position each ring with the gap as shown in the figure referring to the piston front mark .

  

  	: Top ring gap
  	: Oil ring upper or lower rail gap (either of them)
  	: Second ring and oil ring spacer gap
  	: 90 degrees
  	: 45 degrees

• Check the piston ring side clearance. Refer to Inspection.

Install connecting rod bearings to connecting rod and connecting rod bearing cap.

CAUTION:

Never drop connecting rod bearing, and to scratch the surface.

• Before installing connecting rod bearings, apply engine oil to the bearing surface (inside). Do not apply engine oil to the back surface, but thoroughly clean it.

  

• Ensure the oil hole on connecting rod and that on the corresponding bearing are aligned.

Install piston and connecting rod assembly to crankshaft.

• Position crankshaft pin corresponding to connecting rod to be installed onto the bottom dead center.

• Apply engine oil sufficiently to the cylinder bore, piston and crankshaft pin journal.

• Match the cylinder position with the cylinder number on connecting rod to install.

• Be sure that front mark on piston crown is facing the front of the engine.

• Using a piston ring compressor [SST: EM03470000 (NI-8037)] (A) or suitable tool, install piston with the front mark on the piston crown facing the front of the engine.

  

CAUTION:

Never damage the cylinder wall and crankshaft pin, resulting from an interference of the connecting rod big end.

Install connecting rod bearing cap.

• Match the stamped cylinder number marks on connecting rod with those on connecting rod bearing cap to install.

  

  	: Sample codes
  	: Small-end diameter grade
  	: Big-end diameter grade
  	: Weight grade
  	: Cylinder No.
  	: Management code
  	: Management code

• Be sure that front mark on connecting rod bearing cap is facing the front of the engine.

Tighten connecting rod bolt as follows:Inspect the outer diameter of connecting rod bolt. Refer to Inspection. Apply engine oil to the threads and seats of connecting rod bolts. Tighten connecting rod bolts.

: 28.4 N·m (2.9 kg-m, 21 ft-lb)

Completely loosen connecting rod bolts.

: 0 N·m (0 kg-m, 0 in-lb)

Tighten connecting rod bolts.

: 24.5 N·m (2.5 kg-m, 18 ft-lb)

Then turn connecting rod bolts 90 degrees clockwise (angle tightening).

CAUTION:

Always use the angle wrench [SST: KV10112100 (BT-8653-A)] (A). Never make judgment by visual inspection.

• After tightening connecting rod bolts, check that crankshaft rotates smoothly.

• Check the connecting rod side clearance. Refer to Inspection.

Install oil pump.Refer to Removal and Installation.

Install baffle plate.Refer to Disassembly and Assembly.

Install oil strainer.Refer to Disassembly and Assembly.

Install knock sensors .

: Engine front

• Install knock sensor so that connector faces the rear of the engine.

• After installing knock sensor, connect harness connector, and lay it out to rear of the engine.

CAUTION:

• Never tighten mounting bolts while holding connector.

• If any impact by dropping is applied to knock sensor, replace it with new one.

NOTE:

• Check that there is no foreign material on the cylinder block mating surface and the back surface of knock sensor.

• Check that knock sensor does not interfere with other parts.

Install new rear oil seal. Refer to Removal & Installation.

• Apply new engine oil to both oil seal lip and dust seal lip.