Engine Mechanical - 3.5L: Overhaul Nissan Altima L31

Disassembly

1. Remove valve lifter. Mark position for installation.
2. Remove valve collet. Compress valve spring with valve spring compressor. Remove valve collet with magnet driver.
3. Remove valve spring retainer, valve spring, and valve spring seat.
4. Push valve stem to combustion chamber side, and remove valve, mark for assembly. Inspect valve guide clearance before removal. Refer to «VALVE GUIDE CLEARANCE»(ref-163530-S11931516182005050200000) . Confirm installation point.
5. Remove the valve oil seals.
6. If valve seat must be replaced, Refer to «VALVE SEAT REPLACEMENT»(ref-163530-S01860143182005050200000) .
7. If valve guide must be replaced, Refer to «VALVE GUIDE REPLACEMENT»(ref-163530-S00071797082005050200000) .
8. Remove spark plug with spark plug wrench.

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1. Install valve guide. Refer to «VALVE GUIDE REPLACEMENT»(ref-163530-S00071797082005050200000) .
2. Install valve seat. Refer to «VALVE SEAT REPLACEMENT»(ref-163530-S01860143182005050200000) .
3. Install new valve spring seats and new valve oil seals. Install with valve oil seal drift to match dimension in illustration.
4. Install the valves in their original position, as marked during disassembly.
5. Install valve spring (uneven pitch type). Install smaller pitch end (paint mark) to cylinder head side (valve spring seat side).
6. Install valve spring retainer.
7. Install valve collet. Compress valve spring with valve spring compressor. Install valve collet with magnet hand. Tap stem edge lightly with plastic hammer after installation to check its installed condition.
8. Install valve lifter.
9. Install spark plug with spark plug wrench.

DISASSEMBLY AND ASSEMBLY

Note. Flywheel removal may require use of special tool J-46531 (TP55 Torx Plus driver) for M/T flywheel bolts. See ESSENTIAL TOOL: TORX DRIVER FOR FLYWHEEL BOLTS for more information.

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1. Remove the engine assembly. Refer to «ENGINE ASSEMBLY»(ref-163530-S13602720932005050200000) .
2. Install the engine on the engine stand.
3. Remove the knock sensor.
4. Drain the engine of all coolant and oil.
5. Remove the oil pan. Refer to «Removal and Installation»(ref-163530-S34252391802005050200000) .
6. Remove the timing chain. Refer to «Removal»(ref-163530-S34037374582005050200000) .
7. Remove the cylinder head. Refer to «REMOVAL AND INSTALLATION»(ref-163530-S23509705872005050200000) ".
8. Remove the piston and connecting rod assemblies. Position the crankshaft pin corresponding to the connecting rod to be removed onto the bottom dead center. Remove the connecting rod cap. Using a hammer handle or similar tool, push the piston and connecting rod assembly out to the cylinder head side. Before removing the piston and connecting rod assembly, check the connecting rod side clearance. Refer to «CONNECTING ROD»(ref-163530-S26498058062005050200000) .
9. Remove the connecting rod bearings. CAUTION: When removing the connecting rod side bearings, note the installation position. Keep them in the correct order.
10. Remove the piston rings from the piston. Use a piston ring expander. CAUTION: When removing the piston rings, be careful not to damage the piston. Do not expand the rings excessively. Be careful to mark the rings if they are to be reused so they are installed in their original position. Before removing the piston rings, check the piston ring side clearance. Refer to «PISTON RING SIDE CLEARANCE»(ref-163530-S33926005752005050200000) .
11. Remove the piston from the connecting rod as follows. Using a snap ring pliers, remove the snap ring. Heat the pistons to 60° - 70°C (140° - 158°F). Push out the piston pin with a suitable tool, with an outer diameter approximately 20 mm (0.8 in).
12. Remove the rear oil seal retainer from the cylinder block. Insert a screwdriver or similar tool between the rear end of the crankshaft counter weight and rear oil seal retainer, and separate the liquid gasket to remove. CAUTION: Be careful not to damage the mating surface. NOTE: When replacing the rear oil seal during on-vehicle service, it is necessary to remove the oil pan. Refer to «REMOVAL AND INSTALLATION»(ref-163530-S34252391802005050200000) .
13. Loosen the bolts in the numerical order as shown and remove the main bearing beam, bearing caps and crankshaft. Before loosening the main bearing cap bolts, measure the crankshaft side clearance. Refer to «CRANKSHAFT»(ref-163530-S19732578062005050200000) .
14. Remove the oil jets.
15. Remove the main bearings and thrust bearings from the cylinder block and main bearing caps. When removing them, note the direction and position. Keep them in the correct order for installation.
16. If the pilot bushing (M/T) or converter (A/T) must be removed, remove it from the rear end of the crankshaft using a pilot bearing puller.

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1. Install the oil jets. Insert the oil jet knock pin into the cylinder block knock pin hole, and tighten the mounting bolts.
2. Set the upper main bearings in their proper positions on the cylinder block. Confirm the correct main bearings are used. Refer to «PISTON-TO-BORE CLEARANCE»(ref-163530-S37287490052005050200000) .
3. Instructions for the re-use of the main bearing cap bolts. A plastic zone tightening method is used for tightening the main bearing cap bolts. Measure d1 and d2 as shown. For d2, select the minimum diameter in the measuring area. If the difference between d1 and d2 exceeds the limit, replace the bolts for assembly. Limit (d1 - d2): 0.11 mm (0.0043 in)
4. After installing the crankshaft, lower main bearings, main bearing caps, main bearing beam, and bearing cap bolts. Tighten the bearing cap bolts in the numerical order as shown. Make sure that the front marks on the main bearing beam faces the front of the engine. Prior to tightening all the bearing cap bolts, place the bearing beam in its proper position by shifting the crankshaft in the axial position. After tightening the bearing cap bolts, make sure the crankshaft turns smoothly. Lubricate the threads and seat surfaces of the bolts with new engine oil. Tighten the bolts in two stages: CAUTION: Measure the tighten angle in stage 2 with an angle wrench. Do not measure visually. Stage 1: 32 - 38 N.m (3.3 - 3.9 kg-m, 24 - 28 ft-lb) Stage 2: 90° - 95° degrees clockwise
5. Measure crankshaft end play. If beyond the limit, replace the bearing with a new one. Standard: 0.10 - 0.25 mm (0.0039 - 0.0098 in) Limit: 0.30 mm (0.0118 in)
6. Install the rear oil seal retainer. Apply sealant to rear oil seal retainer as shown. Use Genuine RTV Silicone Sealant, or equivalent. Refer to «RECOMMENDED CHEMICAL PRODUCTS AND SEALANTS»(ref-177331-S04337218152005052600000) .
7. Install the piston to the connecting rod. Using suitable snap ring pliers, install the snap ring into the pin-groove of the piston rear side. Insert it fully into groove to install. Install the piston to the connecting rod. Heat the piston until the piston pin can be pushed in by hand without excess force [approx. 60° - 70°C (140° to 158°F)]. From the front to the rear, insert the piston pin into the piston and through 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. Install the snap ring into the front of the piston pin-groove. After installing, check that the connecting rod pivots smoothly on the pin.
8. Using a piston ring expander, install the piston rings. CAUTION: Be careful not to damage the piston. When the piston rings are not replaced, remount the rings in their original positions. When replacing the piston rings, those without punch-marks can be mounted either side up. Position each ring with the gap as shown, referring to the piston front mark. Install the top ring and the second ring with the stamped surface facing upward. If the ring is not stamped it can face in either direction.
9. Install the connecting rod bearings to the connecting rod and the connecting rod cap. When installing the connecting rod bearings, apply engine oil to the bearing surface (crankshaft side). Do not apply oil to the back surface (connecting rod and cap side), but thoroughly clean it. When installing, align the connecting rod bearing protrusion with the notch of the connecting rod to install. Check that the oil holes on the connecting rod and on the corresponding bearing are aligned.
10. Install the piston and connecting rod assembly into the corresponding cylinder. Position the crankshaft pin corresponding to the connecting rod to be installed onto the bottom dead center. Apply engine oil sufficiently to the cylinder bore, piston, and crankshaft pin. Match the cylinder position with the cylinder No. on the connecting rod to install. Using a piston ring compressor, install the piston with the front mark on the piston crown facing the front of the engine. CAUTION: Be careful not to damage the crankshaft pin and cylinder wall, resulting from an interference of the connecting rod big end.
11. Install the connecting rod cap. Match the stamped cylinder number marks on the connecting rod with those on the cylinder cap for installation. Install the piston connecting rod assembly and cap so that the front mark on the cap and piston are facing the front of the engine. Lubricate the threads and seat surfaces with new engine oil.
12. Check the connecting rod cap bolts before reusing, then install in their original position in the connecting rod. The bolts should screw in smoothly by hand. Measure the outer diameter of the connecting rod cap bolt as shown. Outer diameter "d" of the connecting rod bolt Standard: 7.90 - 8.00 mm (0.3110 - 0.3150 in) Limit: 7.75 mm (0.3051 in)
13. Tighten the connecting rod nuts in two stages: Stage 1: 19 - 21 N.m (1.9 - 2.1 kg-m, 14 - 15 ft-lb) Stage 2: 90° - 95° degrees clockwise CAUTION: Always use either an angle wrench or protractor. Avoid tightening based on visual check alone. Apply engine oil to the threads and seats of the connecting rod bolts and nuts. After tightening the nuts, make sure that the crankshaft rotates smoothly. Check the connecting rod side clearance. If beyond the limit, replace the connecting rod and/or crankshaft. Connecting rod side clearance: Standard: 0.20 - 0.35 mm (0.0079 - 0.0138 in) Limit: 0.40 mm (0.0157 in)
14. 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 the rear of the engine. Do not tighten the mounting bolts while holding the connector. Make sure that the knock sensor does not interfere with other parts. CAUTION: If any impact by dropping occurs to the knock sensor, replace it with new one.
15. Install the pilot bushing (M/T) or converter (A/T) as shown.
16. Install the flywheel (M/T), or the drive plate (A/T).
17. Install the cylinder head. Refer to «REMOVAL AND INSTALLATION»(ref-163530-S23509705872005050200000) .
18. Install the timing chain. Refer to «INSTALLATION»(ref-163530-S38848944172005050200000) .
19. Install the oil pan. Refer to «REMOVAL AND INSTALLATION»(ref-163530-S34252391802005050200000) .
20. Remove the engine from the stand and install the engine assembly into the vehicle. Refer to «REMOVAL AND INSTALLATION»(ref-163530-S33260878492005050200000) .
21. Assembly of the remaining parts is in the reverse order of disassembly.
22. Fill the engine with the specified oil and coolant. CAUTION: Wait at least 30 minutes for the sealant to set-up before filling the engine with fluids and running it.

Scheme 416

1. Measure the inner diameter of piston pin bore "dp". Standard diameter "dp" Grade No. 0: 21.993-22.999 mm (0.8659-0.8661 in) Grade No. 1: 21.999-22.005 mm (0.8661-0.8663 in)

Scheme 417

1. Measure outer diameter of piston pin "Dp". Standard diameter "Dp" Grade No. 0: 21.989-21.995 mm (0.8657-0.8659 in) Grade No. 1: 21.995-22.001 mm (0.8659-0.8662 in)