Procedure H - Engine Replacement Tips

Procedure H - Engine Replacement Tips:

NOTE:
^ This procedure does not contain a step-by-step engine replacement procedure.

^ It only provides informational tips related to replacing an engine.

^ Please refer to the applicable Service Manual as your main source of information.

^ The following informational tips are included in Procedure H:

- Precautions

- Removal Tips

- Installation Tips

- Torque Specifications

- Special Tools

Precautions

^ Use suitable covers to protect exterior (fenders, grille, etc.) and interior (upholstery, carpet, etc.) when performing this procedure.

^ Make sure the parking brake is applied and the front and rear wheels are blocked to prevent vehicle movement.

^ Do NOT start work until the cooling and exhaust systems are cooled off.

^ Make sure the correct vehicle lift points are used when raising the vehicle. Also, make sure the vehicle is properly positioned (balanced) on the lift, considering that the engine will be removed.

^ Use a torque wrench when installing nuts and bolts.

^ Refer to the Torque Charts on pages 44 through 48 and the applicable Service Manual for Torque Specifications when re-installing and tightening nuts and bolts.

^ Cover openings of any vehicle/engine systems that are disconnected/opened to keep out "foreign" materials from getting in.

^ Carefully mark and arrange disassembled parts in an organized way for proper re-installation.

^ Use care during disassembly/re-assembly NOT to damage sliding or "mating" surfaces.

^ Make sure all sliding and mating surfaces are clean and free of debris before reassembly.

^ Make sure the new engine has the alignment dowels installed in the rear of the block. There should be two of them (located diagonal to each other).

^ Use special tools as needed. Refer to the Special Tools List.

^ Always work safely and avoid using too much force.

Removal Tips

Variable Valve Timing (VVT) Wire Harness Connector (Altima and Sentra)





^ Make sure the VVT Wire Harness Connector is disconnected before removing the engine (see Figure H1).

Crankshaft Position Sensor (Altima and Sentra)





^ Remove the Crankshaft Position Sensor before separating the engine and transmission. Do NOT damage the edge of the Crankshaft Position Sensor or the ring gear teeth. Pull the sensor straight out to help avoid damage. See Figure H2.

^ To release the wire harness connector, push IN on the release tab, then PULL the connector OFF.

Passenger Side Lower Motor Mount Bolt (Altima ONLY)





^ The Passenger Side Lower Motor Mount Bolt can be difficult to see. Before you remove the engine, remember to remove this bolt. See Figure H3.

Center Member (Sentra ONLY)





Remove the Center Member, but leave the Rear Engine Mount on the engine (see Figure H4).

Axle Shafts Removal (Altima and Sentra)

^ Be careful NOT to damage the oil seals in the transaxle when removing both axle shafts. Support the axles properly and pull them straight out to help prevent damage.

Front Lower Control Arms (Altima and Sentra)

^ After disconnecting the Front Lower Control Arms from the vehicle underbody, tie them back for clearance when you remove the engine.

Power Steering Hose Support Bracket Bolts (Altima ONLY)





^ Make sure to remove the Power Steering Hose Support Bracket Bolts before engine removal (see Figure H5).

Power Steering Pipe Clamps (Altima ONLY)





^ Remove the Power Steering Pipe Clamps on the engine cradle before removing the engine (see Figure H6).

Coolant Pipe (Altima ONLY)





^ Disconnect the Coolant Hoses from the Metal Coolant Pipe, but leave the metal pipe on the engine (see Figure H7).

Torque Converter/Lower Bell Housing Bolts (Altima and Sentra)





^ Remove the Torque Converter and Lower Bell Housing Bolts before removing the engine. It's easier to do this before the engine is out of the vehicle. See Figure H8.

A/T Revolution Sensor Wire Harness Connectors (Altima and Sentra)





^ Make sure you mark the A/T Revolution Sensor Wire Harness Connectors for proper re-installation (see Figure H9). If these connectors are "mixed up", improper transmission shifting can occur.

TOD Rear Main Harness Support Bracket (Altima and Sentra)

^ Remove the bolt that secures the Top Rear Main Harness Support Bracket to the engine before engine removal (see Figure H10).

Wire Harness Support Bracket (Altima ONLY)





^ Remove one bolt to release the Wire Harness Support Bracket (see Figure H11).

Torx Sockets for Flywheel/Flex Plate to Crankshaft Bolts (Altima and Sentra)

^ Torx TP5O (J-45737): Use for M/T with engine number before (but not including) 308509Z

NOTE:
Do NOT use a standard T50 Torx bit as it can break or strip out.

^ Torx TP55 (J-46531): Use for M/T with engine number 308509Z and later

NOTE:
Do NOT use a standard T55 Torx bit as it can break or strip out.

^ Torx E20 Socket (J-45816): Use for all A/T equipped vehicles (W/ QR25DE engine).

NOTE:
Do NOT use a standard external Torx socket as it can "round off" the bolt head.

IMPORTANT:
Do NOT use an air tool with the above noted Torx bits/socket.

Installation Tips

Front Suspension Member 'Engine Cradle (Altima ONLY)

^ Install the front bolts securing the Front Suspension Member and allow the rear (of the suspension member) to hang down slightly. This will allow access for re-installation of the components in this area.

^ Vehicle must be on the ground when torquing all Suspension Member mounting nuts.

Torque Converter to Flex Plate Securing (Altima and Sentra)





^ Use a screwdriver to move the Torque Converter up or down to align the Torque Converter bolt holes with the Flex Plate bolt holes. See Figure H12.

^ Make sure the bolt "shoulder is fully seated in the mounting hole.

Engine Block Alignment Dowels (Altima and Sentra)

^ Make sure the new engine has the alignment dowels installed in the rear of the block. There should be two of them (located diagonal to each other).

Filling (50/50 Mixture) Coolant System (Altima and Sentra)

^ Use genuine Nissan engine coolant.

^ Use the Engine Coolant Refill Tool # J-45695 to ensure complete filling without air bubbles ("pockets") in the cooling system.

^ For proper heater performance, it is IMPORTANT that the cooling system be filled with an accurate mixture of 50% coolant and 50% water and all air bubbles be purged from the system.

^ See NTB02-047a (2002 - 2003 Altima: Poor Heater Performance) for additional information on Altima cooling system refill procedures.

Torque Specifications

A/T and M/T Bell Housing Bolt Tightening Sequence (Altima and Sentra)





^ Tighten the bolts that secure the transmission bell housing to the engine in the sequence shown in Figure H13 below.

CAUTION:

^ The engine and transmission must be fully mated together before tightening the bolts. Do NOT use the bolts to pull the engine and transmission together.

Torque Specifications (Altima and Sentra)











^ Refer to the Illustrations for torque specifications. See the applicable Electronic Service Manual for other torque specifications (as needed).





Altima and Sentra

Special Tools

Special Tools (Altima and Sentra)





Refer to the chart (Figure H19) for Special Tool applications.

NOTE:
Replacement tools can be ordered from Tech-Mate.