Lexus RX300 (MCU15). Service manual - part 438

A05205

A05188

Rear
Plate

Inlet Pipe

A05189

A05190

A05191

EM–36

–

ENGINE MECHANICAL

CYLINDER HEAD

LEXUS RX300   (RM785E)

24.

DISCONNECT ENGINE WIRE PROTECTOR FROM LH
SIDE

Remove the 2 bolts, and disconnect the engine wire protector
from the LH cylinder head cover.

25.

DISCONNECT CYLINDER HEAD REAR PLATE
FROM LH CYLINDER HEAD

Remove the 2 bolts, and disconnect the rear plate.
26.

DISCONNECT WATER INLET PIPE FROM LH
CYLINDER HEAD AND WATER INLET

(a)

Remove the bolt, and disconnect the inlet pipe from the
water inlet.

(b)

Remove the O–ring from the inlet pipe.

27.

REMOVE PS PUMP BRACKET

Remove the 3 bolts and pump bracket.

28.

REMOVE RH EXHAUST MANIFOLD

(a)

Disconnect the A/F sensor (bank 1 sensor 1) connector.

(b)

Remove the bolt, nut and exhaust manifold stay.

(c)

Remove the 6 nuts, exhaust manifold and gasket.

29.

REMOVE WU–TWC

Remove the 2 nuts, WU–TWC and gasket.

30.

REMOVE LH EXHAUST MANIFOLD

(a)

Disconnect the A/F sensor (bank 2 sensor 1) connector.

(b)

Remove the bolt, nut and exhaust manifold stay.

(c)

Remove the 6 nuts, exhaust manifold and gasket.

A05192

O–Ring

A05193

A05280

Align

Intake:

A05195

Intake:

Main Gear

Sub–Gear

Service Bolt

–

ENGINE MECHANICAL

CYLINDER HEAD

EM–37

LEXUS RX300   (RM785E)

31.

REMOVE OIL DIPSTICK AND GUIDE

(a)

Remove the bolt holding the dipstick guide to the LH cylin-
der head.

(b)

Pull out the dipstick guide together with the dipstick from
the No. 1 oil pan.

(c)

Remove the O–ring from the dipstick guide.

32.

REMOVE CYLINDER HEAD COVERS

Remove the 9 bolts, cylinder head cover and gasket. Remove
the 2 cylinder head covers.

33.

REMOVE CAMSHAFTS OF RH CYLINDER HEAD

NOTICE:
Since the thrust clearance of the camshaft is small, the
camshaft must be held level while it is being removed. If the
camshaft is not kept level, the portion of the cylinder head
receiving the shaft thrust may crack or be damaged, caus-
ing the camshaft to seize or break. To avoid this, the follow-
ing steps should be carried out.

(a)

Remove the intake camshaft.
(1)

Align the timing marks (2 dot marks) of the camshaft
drive and driven gears by turning the camshaft with
a wrench.

(2)

Secure the exhaust camshaft sub–gear to the main
gear with a service bolt.

Recommended service bolt:
Thread diameter: 6 mm
Thread pitch: 1.0 mm
Bolt length: 16 – 20 mm

HINT:
When removing the camshaft, mark certain that the torsional
spring force of the sub–gear has been eliminated by the above
operation.

A05207

Intake:

7

8

5

6

3

4

1

2

9

10

A05197

7

8

5

6

3

4

1

2

9

10

Exhaust:

A05284

Align

Intake:

A05198

Intake:

Main Gear

Sub–Gear

Service Bolt

EM–38

–

ENGINE MECHANICAL

CYLINDER HEAD

LEXUS RX300   (RM785E)

(3)

Uniformly loosen and remove the 10 bearing cap
bolts, in several passes, in the sequence shown.

(4)

Remove the 5 bearing caps and intake camshaft.

(b)

Remove the exhaust camshaft.
(1)

Uniformly loosen and remove the 10 bearing cap
bolts, in several passes, in the sequence shown.

(2)

Remove the 5 bearing caps, oil seal and exhaust
camshaft.

34.

REMOVE CAMSHAFTS OF LH CYLINDER HEAD

NOTICE:
Since the thrust clearance of the camshaft is small, the
camshaft must be held level while it is being removed. If the
camshaft is not kept level, the portion of the cylinder head
receiving the shaft thrust may crack or be damaged, caus-
ing the camshaft to seize or break. To avoid this, the follow-
ing steps should be carried out.

(a)

Remove the intake camshaft.
(1)

Align the timing marks (1 dot mark) of the camshaft
drive and driven gears by turning the camshaft with
a wrench.

(2)

Secure the exhaust camshaft sub–gear to the main
gear with a service bolt.

Recommended service bolt:
Thread diameter: 6 mm
Thread pitch: 1.0 mm
Bolt length: 16 – 20 mm

HINT:
When removing the camshaft, make sure that the torsional
spring force of the sub–gear has been eliminated by the above
operation.

A05199

Intake:

7

8

5

6

3

4

1

2

9

10

A05200

7

8

5

6

3

4

1

2

9

10

Exhaust:

P12596

P12797

SST

P12590

–

ENGINE MECHANICAL

CYLINDER HEAD

EM–39

LEXUS RX300   (RM785E)

(b)

Uniformly loosen and remove the 10 bearing cap bolts, in
several passes, in the sequence shown.

(c)

Remove the 5 bearing caps and intake camshaft.

(d)

Remove the exhaust camshaft
(1)

Uniformly loosen and remove the 10 bearing cap
bolts, in several passes, in the sequence shown.

(2)

Remove the 5 bearing caps, oil seal and exhaust
camshaft.

HINT:

S

Arrange the camshafts in the correct order.

S

Arrange the bearing caps in the correct order.

35.

DISASSEMBLE EXHAUST CAMSHAFTS

(a)

Mount the hexagonal wrench head portion of the cam-
shaft in a vise.

NOTICE:
Be careful not to damage the camshaft.

(b)

Using SST, turn the sub–gear counterclockwise, and re-
move the service bolt.
SST

09960–10010 (09962–01000, 09963–00500)

(c)

Using snap ring pliers, remove the snap ring.

(d)

Remove the wave washer.

(e)

Remove the camshaft sub–gear.

(f)

Remove the camshaft gear spring.

HINT:
Arrange the camshaft sub–gears and gear springs (RH and LH
side).