11 21 505 Sealing crankcase lower section (N20, N26)

Special tools required:

IMPORTANT: Changed procedure.
It is not necessary to remove the cylinder head and the crankshaft.

Necessary preliminary tasks:

Remove ENGINE .
Mount ENGINE on assembly stand.
Remove clutch . See 21 21 500 REMOVING AND INSTALLING OR REPLACING CLUTCH (SAC 240) or 21 21 500 REMOVING AND INSTALLING OR REPLACING CLUTCH (SAC 350) (if fitted).
Remove left and right engine support arm. See 22 11 110 REPLACE LEFT ENGINE SUPPORT ARM (N20, B26) and 22 11 100 REPLACING RIGHT ENGINE SUPPORT ARM (N20, N26) .
Remove oil sump . See 11 13 000 REMOVING AND INSTALLING, SEALING OR REPLACING OIL SUMP (N20, N26) or 11 13 000 REMOVING AND FITTING, SEALING OR REPLACING THE OIL SUMP (N20 ALL-WHEEL DRIVE VEHICLE) .
Remove VIBRATION DAMPER .
Remove COUNTERBALANCE SHAFT .

Release hose clamp (1) and detach coolant hose.

Tightening torque: 11 51 3AZ

Unfasten plug connection (2) and disconnect.

Release screws (3) and remove coolant pump.

Tightening torque: 11 51 2AZ

Fig 1: Identifying Coolant Pump Plug Connection And Screws

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Release screw (1).

Tightening torque 11 42 6AZ .

Remove oil return line (2).

Installation note:

Replace O-ring.

Remove vent line (3).

Fig 2: Identifying Oil Return Line, Vent Line Screw

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NOTE: The dowel hole for the TDC setting is on the exhaust side below the exhaust manifold.

Rotate engine at central bolt and secure flywheel in position with special tool 11 0 300 .

Fig 3: Securing Flywheel With Special Tool (11 0 300)

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Secure flywheel with special tool (1) 11 9 260 .

NOTE: Ensure that special tool 11 9 260 is fully engaged in the flywheel gearing.

Fig 4: Identifying Special Tool (11 9 260)

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Automatic transmission:

Release flywheel bolts (1).

Release special tool (2).

Remove flywheel (3).

Fig 5: Removing Flywheel Bolts Using Special Tool

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Manual gearbox:

IMPORTANT: Position crankshaft at TDC.

Remove dual-mass flywheel.

Secure flywheel with special tool 11 9 260 .

Release flywheel bolts with special tool 11 4 180 /

Fig 6: Locating Flywheel Bolts

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IMPORTANT: Magnet wheel (1) is magnetic.
Keep magnet wheel (1) in a plastic bag away from metal shavings.

Remove magnet wheel (1) from crankshaft.

Installation note:

Check the fitting sleeve for damage.

Note the installation position of the magnet wheel.

Fig 7: Identifying Magnet Wheel

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Release screw on pulse sensor (1).

Slide PULSE SENSOR (2) upwards.

Fig 8: Identifying Pulse Sensor

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Fig 9: Identifying Crankcase Bolts Line

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Release all crankcase bolts (1) along line (2).

Release crankcase bolts M10 in sequence 10 to 1.

Fig 10: Crankcase Lower Section Bolts Tightening/Loosening Sequence (N20)

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Release crankcase lower section (1) from crankcase upper section (2) with suitable tool (3)

Remove crankcase lower section (1) upwards.

IMPORTANT: Do not rotate crankshaft without crankcase lower section (1) (risk of damage).

Fig 11: Releasing Crankcase Lower Section Using Tool

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IMPORTANT: Timing chain is preloaded.
Do not raise crankshaft.

Carefully remove radial shaft seal (1).

Catch escaping engine oil with a cloth (2).

Fig 12: Removing Radial Shaft Seal

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Carefully remove radial shaft seal (1) towards front.

Catch escaping engine oil with a cloth (2).

Fig 13: Removing Radial Shaft Seal

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IMPORTANT: Protect crankcase against sealant residues with a cloth (1).
Remove sealing compound residues (1) with special tool 11 4 470 .

Fig 14: Identifying Crankcase Protecting Cloth

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Installation note:

Check durability of sealing compound, do not use sealing compound that has expired.

Maximum processing time of the SEALING COMPOUND 2.2 10 minutes.

Apply sealing compound in the stated areas with a width of 2.0 to 2.6 mm.

Fig 15: Identifying Sealing Compound Applying Areas

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Fit crankcase lower section (watch fitting bushes).

Fig 16: Installing Crankcase Lower Section

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Screw in all M10 crankcase screws in the sequence 1 to 10 and tighten with JOINTING TORQUE .

Fig 17: Crankcase Lower Section Bolts Tightening/Loosening Sequence (N20)

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Identify all M10 crankcase bolts with a colored marking (1) for checking.

Fig 18: Identifying Crankcase Bolts

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Retighten all screws using special tool 00 9 120 , observing the specified sequence.

Tightening torque 11 11 1AZ .

Installation note:

After tightening all screws, the colored mark must be aligned in the same way.

Fig 19: Tightening Screws Using Special Tools (00 9 120)

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Fig 20: Identifying Crankcase Bolts Line

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Insert all crankcase screws (1) and tighten from the inside to the outside.

Tightening torque: 11 11 2AZ .

IMPORTANT: The following text describes the installation and sealing between the engine block and crankshaft seal at the front.
The engine block will not be leak proof at the outside of the crankshaft seal if you fail to comply with the individual work steps and the work sequence.

Connect supporting sleeve (1) to special tool 2 212 822 .

Position radial shaft seal (2) carefully in direction of arrow on special tool 2 212 822 .

Fig 21: Positioning Radial Shaft Seal