BMW 3 Series Service Manual (E39)

113-27

Cylinder Head Removal and Installation

<-Remove fuel rail mounting bolts (arrows): Carefully pry fuel rail off manifold.

Separate fuel line support bracket at rear of intake manifold.

Guide fuel line(s) out of rear of engine compartment while lifting fuel rail out.

4 Remove intake manifold mountino hardware (arrows).

4 -Remove cylinder head top cover: Remove plastic trim caps (arrows).

Remove cover hold down fasteners and lilt off cover.

ICylinder Head Removal and Installation

4Drain engine coolant and remove coolant hoses: Remove expansion tank cap on radiator.

Place a 3 gallon pail beneath engine to capture coolant

Remove coolant drain plug (arrow) located on exhaust side of cylinder 2 of engine block.

4Drain radiator into a 3 gallon pail by removing plastic drain plug (arrow) completely.

Use caution when draining and disposingof engine coolant. Coolantispoisonousandlethal to humansandpets. Petsare attractedto coolant becauseof its sweetsmell and taste.

Seek medicalattention immediatelyif coolant is ingested.

NOTE-

Catch and dispose of drained coolant according to local, state, and federal laws.

4Remove thermostat housing:

.Disconnect electrical harness connector at thermostat housing.

.Remove hosesfrom thermostat hous~ngby releasingloclts (arrows).

Unbolt (4 bolts) and remove thermostat hous~ng.

-On vehicles equipped with mechanical cooling fan: Remove belt-driven cooling fan and radiator shroud as described in 170 Radiator and Cooling System.

rCAUTIOI\C

32mm radiator fan mountingnut has left hand threads.

4 Remove fasteners (arrows) from heater bypass tube. Pull tube out of cylinder head and set to side, leaving heater hose connected.

-Unbolt power steering fluid reservoir and pull aside without disconnecting hoses. Secure to fender with cord or stiff wire.

4 Disconnect electrical harness connections at exhaust camshaft position sensor and exhaust camshaft VANOS control valve (arrows).

4 Remove banjo bolt from VANOS unit oil pressure line. Use banjo bolt to attach BMW special tool 11 3 450 (compressed air fitting) to VANOS control unit.

CAUTIOI\C

Oil willdrain from pressure line. Have a drain containerand rags ready Do not allow oil to run onto drive belts.

4 Cover oil hole (arrow) in VANOS unit with shop towel to capture oil which will spray when compressed air is applied.

-Connect compressed air line to air fitting. Apply air pressure set to 2-8 bar (30-1 15 psi).

4 With compressed air line connected, rotate engine at vibration damper in direction of rotation (clockwise)at least twice, until cylinder 1 intake and exhaust camshaft lobes face each other (arrows) in the top dead center (TDC) position for cylinder 1.

CAUTION--

Do not rotate engine counterclocltwise to reach the top dead centerposition. If engine rotatedbeyondtop dead center; complete another two complete rotations.

113-31

Cylinder Head Removal and Installation

Remove sealing plug from special tool bore on lower left side of engine block near flywheel. Secure crankshaft in TDC position with BMW special tool l l 2 300 (arrow).

4 Unscrew and remove two cylinder head cover studs (arrows) at rear of cylinder head.

4 Secure camshafts in TDC position using BMW special tool set 11 3 240.

-Disconnect compressed air line, leaving compressed air fit ting attached to VANOS unit.

4 Unscrew sealing plugs (arrows) from VANOS unit.

Pull sealing caps straight out of VANOS unit using short needle nose pliers.

NOTE-

Additional oil may drain from VANOS unit.

Remove set screws (left-hand thread) on ends of intake and exhaust camshafts.

CAUTION-

Set screws have left-hand threads. Loosen inclocltwise direction.

Remove VANOS unit:

-Remove engine lifting eye.

Remove VANOS mounting nuts (arrows)and pull VANOS unit and metal gasket off.

CAUTION-

Do not crank the engine with VANOSunit removed. Pistonhalve inteiference may result.

NOTE-

The VANOS unit will contain a small quantity of oil. Place shop towel to catch oil as unit is removed or tilted.

CAUTION-

If the VANOSadjustment unit is replaced, or if operations are completed that may change the timing of the camshafts, the camshaft timing must be checked. See 117Camshaft Timing Chain.

4 Remove primary camshaft chain tensioner cylinder (arrow).

CAUTION-

Primary camshaft chain tensioner is under spring pressure.

Press down on secondary chain tensionerand lock into place using BMW special tool 11 3 291, or a thin drifl or pin.

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ICylinder Head emo oval and Installation-

<Remove exhaust camshaft impulse wheel mounting nuts (arrows). Remove impulse wheel (A).

4 Remove spring plate (A).

4 Remove intake camshaft sprocltet mounting nuts (arrows) and remove spring plate (labelled FRONT).

<Remove torx screws from exhaust camshaft sprocket (arrows).

113-35

<Lift off exhaust and intake sprocltets together with secondary chain, thrust spacer (A), and splined shafl (B).

CAUTION-

Splinedshafts share the same part numberfor both intake andexhaustcamshafts. Usedsplinedshafts mustbe rein- stalledin their originalpositions.

Remove exhaust camshaft splined sleeve (A) and shaft (B).

Removesecondary chain tensloner mounting bolts (arrows) and remove tensioner with retaining pin in place.

113-36

Cylinder Head Removal and Installation

4 Remove sprocket mounting studs (arrows) from exhaust camshaft.

Lift primary chain sprocltet off exhaust camshaft. Remove sprocket from chain.

4 Place timing chain on end of exhaust camshaft

4 Spline retaining screws (arrows) should not be removed from camshaft.