Engine Mechanical: Overhaul Infiniti Q45 III

DISASSEMBLY

Note. Explained here is how to disassemble with engine stand supporting transmission surface. When using different type of engine stand, note with difference in steps and etc.

Scheme 155

Scheme 156

Scheme 157

Scheme 158

Scheme 159

Scheme 160

Scheme 161

Scheme 162

Scheme 163

1. Remove engine assembly. Refer to «ENGINE ASSEMBLY»(ref-231095-S21348120922006050300000) .
2. Remove the parts that may restrict installation of engine to general-purpose engine stand. NOTE: The procedure is described assuming that you use a general-purpose engine stand holding the surface, to which transmission is installed. Remove drive plate. Holding crankshaft pulley mounting bolts, lock crankshaft to remove bolts fixing drive plate. Loosen fixing bolts diagonally. CAUTION: Be careful not to damage drive plate. Especially, avoid deforming and damaging of signal plate teeth (circumference position). Place the drive plate with signal plate surface facing other than downward. Keep magnetic materials away from signal plate. Remove engine rear plate.
3. Lift the engine with hoist to install it onto the general-purpose engine stand. CAUTION: Use an engine stand that has a load capacity [240 kg (529 pound) or more] large enough for supporting the engine weight. If the load capacity of the stand is not adequate, remove the following parts beforehand to reduce the potential risk of overturning the stand. Remove intake manifold upper and intake manifold lower. Refer to «INTAKE MANIFOLD»(ref-231095-S31723550202006050300000) ". Remove exhaust manifold and three way catalyst. Refer to «EXHAUST MANIFOLD AND THREE WAY CATALYST»(ref-231095-S37830332102006050300000) . Remove fuel injector and fuel tube. Refer to , " «FUEL INJECTOR AND FUEL TUBE»(ref-231095-S34108314512006050300000) ". Remove starter motor. Refer to «REMOVAL & INSTALLATION»(ref-167713-S37775669052004102000000) . Remove ignition coil. Refer to «IGNITION COIL»(ref-231095-S21650249192006050300000) . Remove rocker cover. Refer to «ROCKER COVER»(ref-231095-S27210562282006050300000) . Other removable brackets. NOTE: The figure shows an example of general-purpose engine stand that can hold mating surface of transmission with drive plate and rear plate removed. CAUTION: Before removing the hanging chains, make sure the engine stand is stable and there is no risk of overturning.
4. Drain engine oil and engine coolant from inside of engine.
5. Remove the following components and associated parts (The parts listed in step 3 are not included here.) Oil pan and oil strainer: Refer to «OIL PAN AND OIL STRAINER»(ref-231095-S16973930572006050300000) . Crankshaft pulley, front cover and timing chain: Refer to «TIMING CHAIN»(ref-231095-S33811221062006050300000) . Camshaft: Refer to «CAMSHAFT»(ref-231095-S35005084482006050300000) . Cylinder head: Refer to «CYLINDER HEAD»(ref-231095-S06279948502006050300000) .
6. Remove knock sensor. CAUTION: Carefully handle the sensor, avoiding shocks.
7. Remove the piston and connecting rod assembly. 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 SIDE CLEARANCE»(ref-231095-S40723072112006050300000) .
8. Remove the connecting rod bearings. CAUTION: When removing them, note the installation position. Keep them in the correct order.
9. Remove the piston rings form the piston. Use a piston ring expander. CAUTION: When removing the piston rings, be careful not to damage the piston. Be careful not to damage piston rings by expanding them excessively. Before removing the piston rings, check the piston ring side clearance. Refer to «PISTON RING SIDE CLEARANCE»(ref-231095-S42249393512006050300000) .
10. Remove the piston from the connecting rod as follows. Using a snap ring pliers, remove the snap ring. Heat piston to 60 to 70°C (140 to 158°F) with drier or equivalent. Push out piston pin with stick of outer diameter approximately 20 mm (0.8 in).
11. Remove the rear oil seal retainer from the cylinder block. Insert a minus-head 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.
12. Using a minus-head screwdriver or similar tool, and lever off the rear oil seal from the rear oil seal retainer.
13. Remove the main bearing cap as follows: Before loosening the main bearing cap bolts, measure the crankshaft end play. Refer to . " «CRANKSHAFT END PLAY»(ref-231095-S16697085752006050300000) ". Loosen bolts in several different steps. Remove the cover attached to the rear right side of the cylinder block (next to the starter motor housing). NOTE: Bolts (No. 28 shown in the figure) are installed on the inside of the cover. Loosen the side bolts (M10) starting from 30 to 21 to remove. Loosen the main bearing cap sub bolts (M9) starting from 20 to 11 to remove. Loosen the main bearing cap bolts (M12) starting from 10 to 1 to remove. Using a main bearing cap remover, remove the main bearing cap.
14. Remove the crankshaft.
15. Remove the main bearings and thrust bearings from the cylinder block and main bearing caps. When removing them, note the installation position. Keep them in the correct order.
16. If the pilot converter must be removed, remove it from the rear end of the crankshaft using a pilot bearing puller. Removal and installation without the engine stand is possible.

Scheme 164

Scheme 165

Scheme 166

Scheme 167

Scheme 168

Scheme 169

Scheme 170

Scheme 171

Scheme 172

Scheme 173

Scheme 174

Scheme 175

Scheme 176

Scheme 177

Scheme 178

Scheme 179

Scheme 180

Scheme 181

Scheme 182

Scheme 183

1. Fully air-blow the engine coolant and engine oil passages in the cylinder block, the cylinder bore, and the crankcase to remove any foreign material. CAUTION: Use a goggles to protect your eye.
2. Install each plug to the cylinder block. (Only screwed-type plugs are shown in the figure.) Apply liquid gasket. Use Genuine Thread Sealant or equivalent . Refer to «RECOMMENDED CHEMICAL PRODUCTS AND SEALANTS»(ref-182064-S38599864392005080600000) . Replace the copper washers with new ones. Tighten them as specified below.
3. Install the main bearings and the thrust bearings. Remove dust, dirt, and engine oil on the bearing mating surfaces of the cylinder block and the main bearing caps. Install the thrust bearings to the both sides of the No. 3 journal housing on the cylinder block and main bearing caps Install the thrust bearings with the engine oil groove facing the crankshaft arm (outside). Install the thrust bearings with a protrusion in the center on the main bearing caps. Install the main bearings paying attention to the direction. Install the one with oil holes onto the cylinder block and the one without oil holes onto the main bearing cap. Before installing the 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 the bearing stopper to the notch. Insure the oil holes on cylinder block and those on the corresponding bearing are aligned.
4. Install the pilot converter to the crankshaft. Using a drift approximately 35 mm (1.38 in) in outer diameter, drive the pilot converter until its front end contacts the crankshaft. Press-fit the pilot converter with its chamfering side facing the crankshaft. It is acceptable to install it without the engine stand.
5. Install the crankshaft to the cylinder block. While turning the crankshaft by hand, check that it turns smoothly.
6. Install the main bearing caps. Align the identification number to the journal position to install. Install the upper side of the identification number facing the front of the engine. (The number shall be read correctly from the rear of the engine.) Using a plastic hammer or similar tool, tap them lightly to seat them on the installation position.
7. Follow the below steps to tighten each main bearing cap bolts. Apply engine oil to threads and seating surface of bolts, and tighten all bolts temporarily. Tighten main bearing cap bolt (M12) to 36.3 to 42.1 N.m (3.7 to 4.3 kg-m, 27 to 31 ft-lb) in order of 1 to 10. Tighten main bearing cap sub bolt (M9) to 26.5 to 32.3 N.m (2.7 to 3.3 kg-m, 20 to 23 ft-lb) in order of 11 to 20. Tighten main bearing cap bolt (M12) to 40 to 45° degrees (ideal 40 degrees) in order of 1 to 10. Tighten main bearing cap sub bolt (M9) to 30 to 35° degrees (ideal 30 degrees) in order of 11 to 20. Tighten side bolt (M10) to 46.1 to 51.9 N.m (4.7 to 5.3 kg-m, 34 to 38 ft-lb) in order of 21 to 30. Install cover of cylinder block right-rear side (next to starter motor housing). CAUTION: Measure tighten angle in step "d" and "e" with angle wrench. Do not measure visually. Rotate crankshaft by hands after bolts are tightened. Check if it rotates smoothly. Check the crankshaft end play. Refer to «CRANKSHAFT END PLAY»(ref-231095-S16697085752006050300000) ".
8. Install rear oil seal to oil seal retainer. Tap until flattened with front edge of oil seal retainer. Do not damage or scratch outer circumference of oil seal. Install new oil seal in the direction shown in the figure.
9. Install rear oil seal retainer. Apply liquid gasket thoroughly to rear oil seal retainer. Use Genuine RTV Silicone Sealant or equivalent. Refer to «RECOMMENDED CHEMICAL PRODUCTS AND SEALANTS»(ref-182064-S38599864392005080600000) . Apply new engine oil on lips of oil seal. Do not touch.
10. Install the piston to the connecting rod. Using a snap ring pliers, install the snap ring to the grooves of the piston rear side. Insert it fully into groove to install. Install the piston to the connecting rod. Using an industrial drier or similar tool, heat the piston until the piston pin can be pushed in by hand without excess force [approx. 60 to 70 C° (140 to 158 °F)]. 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 the figure. Install the snap rings to the front of the piston. After installing, check that the connecting rod moves smoothly.
11. Using a piston ring expander, install the piston rings. CAUTION: Be careful not to damage the piston. Position each ring with the gap as shown in the figure, referring to the piston front mark. Install the top ring and the second ring with the stamped surface facing upward. Stamped mark : R (top ring) : 2R (second ring)
12. 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 (inside). Do not apply engine oil to the back surface, but thoroughly clean it. 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.
13. Install the piston and connecting rod assembly to the crankshaft. 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, resulting from an interference of the connecting rod big end.
14. Install the connecting rod cap. Match the stamped cylinder number marks on the connecting rod with those on the cylinder cap to install.
15. Tighten the connecting rod nuts as follows: Apply engine oil to the threads and seats of the connecting rod bolts and nuts. Tighten nuts to 13.7 to 15.7 N.m (1.4 to 1.6 kg-m, 10 to 12 ft-lb). Put mating (with paint) on each nut and connecting rod cap, all in the same direction (when using a protractor). Then all nuts 60 to 65 degrees clockwise [target: 60 degrees] (angle tightening). CAUTION: Always use either an angle wrench or protractor. Avoid tightening based on visual check alone. After tightening the nuts, make sure that the crankshaft rotates smoothly. Check the connecting rod side clearance. Refer to «CONNECTING ROD SIDE CLEARANCE»(ref-231095-S40723072112006050300000) .
16. Install 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 it with its connector facing the rear side. Do not tighten the mounting bolts while holding the connector. Make sure that the knock sensor does not interfere with other-parts. Install the sub-harness with its shorter branch line to the RH bank. CAUTION: If any impact by dropping is applied to the knock sensor, replace it with new one.
17. Install followings in reverse order of removal.
18. Remove engine assembly from engine stand.
19. Install drive plate. Align guide pin of crankshaft rear end with pin holes of each parts to install. Install drive plate, reinforcement plate and pilot converter (if not installed in step 4) as shown in figure. Using drift of 33 mm (1.30 in) dia, push pilot converter into the end. Face chamfered or rounded edge side to crankshaft.

Scheme 184

* For the service parts, the grade for fitting cannot be selected between a piston pin and a connecting rod. (Only 0 grade is available.) The information at the shipment from the plant is described as a reference.

1. The identification grade stamped on each part is the grade for the dimension measured in new condition. This grade cannot apply to reused parts.
2. For reused or repaired parts, measure the dimension accurately. Determine the grade by comparing the measurement with the values of each selection table.
3. For details of the measurement method of each part, the reuse standards, and the selection method of the selective fitting parts, refer to the text.