Lexus RX300 (MCU15). Service manual - part 437

A05703

Adjusting Shim
Valve Lifter
Keeper
Spring Retainer
Valve Spring
Spring Seat
z Oil Seal

Valve

z Valve Guide Bushing

LH Cylinder Head Cover

LH Intake 
Camshaft

Snap Ring

Camshaft Sub–Gear

LH Exhaust 
Camshaft

RH Cylinder Head Cover

Gasket

RH Intake 
Camshaft

Camshaft Sub–Gear

Camshaft Gear Spring

RH Exhaust
Camshaft

Wave Washer

Semi–Circular Plug

Semi–Circular
Plug

LH Cylinder Head

Camshaft 
Bearing Cap

z Camshaft Oil Seal

RH Cylinder Head

z RH Cylinder
    Head Gasket

z LH Cylinder Head Gasket

18 (185, 13)

x8

16 (160, 12)

See Page EM–60

1st 54 (550,40)

2nd Turn 90°

N·m (kgf·cm, ft·lbf)

: Specified torque

z Non–reusable part

z Spark Plug

Tube Gasket

Wave Washer

Gasket

Snap Ring

Camshaft Gear Spring

Oil Control Valve Filter

z Gasket

Camshaft Timing
Gear (VVT–i)

z Gasket

z Gasket

Oil Control
Valve Filter

Cylinder Head
Rear Cover

Cylinder Head
Rear Cover

z Gasket

150  (1,530, 110)

NOTICE:

Camshaft

Do not remove or install the camshaft timing 
gear (VVT–i) beside changing VVT–i or the 
camshaft.

z

EM–32

–

ENGINE MECHANICAL

CYLINDER HEAD

LEXUS RX300   (RM785E)

EM0B8–04

A05071

5 mm
Hexagon
Wrench

A05270

(2)

(1)

(3)

(4)

–

ENGINE MECHANICAL

CYLINDER HEAD

EM–33

LEXUS RX300   (RM785E)

REMOVAL

NOTICE:
Do not remove or install the camshaft timing gear (VVT–i)
beside changing VVT–i or the camshaft.
1.

REMOVE OUTER COWL TOP PANEL 
(See page EM–75)

2.

DRAIN ENGINE COOLANT

3.

REMOVE RH FENDER APRON SEAL

4.

REMOVE ALTERNATOR DRIVE BELT
(See page CH–6)

5.

REMOVE PS PUMP (See page SR–22)

6.

REMOVE FRONT EXHAUST PIPE
(See page EM–75)

7.

REMOVE V–BANK COVER

(a)

Using a 5 mm hexagon wrench, remove the 3 nuts.

(b)

Remove the V–bank cover fastener clip and V–bank cov-
er.

8.

REMOVE AIR CLEANER CAP AND CASE ASSEMBLY
(See page EM–75)

9.

REMOVE CRUISE CONTROL ACTUATOR

10.

REMOVE FRONT UPPER SUSPENSION BRACE
(See page EM–75)

11.

REMOVE AIR INTAKE CHAMBER ASSEMBLY

(a)

Disconnect the accelerator cable.

(b)

Disconnect the throttle position sensor connector and
clamps.

(c)

Disconnect the ISC valve connector.

(d)

Disconnect the No. 1 VSV connector for ACIS.

(e)

Disconnect the No. 2 VSV connector for ACIS.

(f)

Disconnect the VSV connector for EVAP.

(g)

Remove the 3 bolts, and disconnect the PS pressure tube
from the air intake chamber, chamber stay and No. 1 en-
gine hanger.

(h)

Disconnect the hoses, cables, strap and clamp:
(1)

PCV hose from PCV valve on RH cylinder head

(2)

Ground strap and cable from intake air control valve
for ACIS

(3)

Ground cable from air intake chamber

(4)

Brake booster vacuum hose from air intake
chamber

A14992

(9)

(7)

(8)

(6)

(5)

A05072

Chamber Stay

Engine
Hanger

A14993

8 mm Hexagon Wrench

A05074

(2)

(1)

A05075

EM–34

–

ENGINE MECHANICAL

CYLINDER HEAD

LEXUS RX300   (RM785E)

(5)

2 water bypass hoses from throttle body

(6)

Air assist hose from throttle body

(7)

Purge hose from pipe on emission control valve set

(8)

2 vacuum hoses from vacuum tank for ACIS

(9)

Engine wire clamp from emission control valve set

(i)

Remove the 2 bolts and No. 1 engine hanger.

(j)

Remove the 2 bolts and air intake chamber stay.

(k)

Using an 8 mm hexagon wrench, remove the 2 bolts, 2
nuts, the air intake chamber assembly and gasket.

12.

REMOVE INTAKE MANIFOLD ASSEMBLY

(a)

Disconnect the 6 injector connectors.

(b)

Disconnect the fuel inlet hose from fuel pipe.

CAUTION:
Perform disconnecting operations of the fuel tube connec-
tor (quick type) after observing the precautions.
(See page FI–1)
(c)

Disconnect the heater hose from intake manifold.

(d)

Remove the 9 bolts, 2 nuts, 2 plate washers, the intake
manifold, delivery pipes and injectors assembly.

A05076

Gasket

A05077

Clamp

Clamp

Clamp

A05206

A05187

–

ENGINE MECHANICAL

CYLINDER HEAD

EM–35

LEXUS RX300   (RM785E)

13.

REMOVE WATER OUTLET

(a)

Disconnect the water temperature sensor connector.

(b)

Disconnect the ground strap connector.

(c)

Disconnect the radiator hose.

(d)

Remove the 2 bolts, 2 nuts and 2 plate washers.

(e)

Disconnect the water bypass hose, and remove the water
outlet.

(f)

Remove the 2 gaskets.

14.

REMOVE IGNITION COILS

15.

REMOVE SPARK PLUGS

16.

REMOVE TIMING BELT
(See page EM–16)

17.

REMOVE CAMSHAFT TIMING PULLEYS
(See page EM–16)

18.

REMOVE NO. 2 IDLER PULLEY
(See page EM–16)

19.

REMOVE NO. 3 TIMING BELT COVER

(a)

Disconnect the 3 engine wire clamps from the timing belt
cover.

(b)

Remove the 6 bolts and timing belt cover.

20.

REMOVE CAMSHAFT POSITION SENSORS

21.

REMOVE CAMSHAFT TIMING OIL CONTROL VALVES

22.

DISCONNECT ENGINE WIRE PROTECTOR FROM
REAR SIDE

Remove the nut, and disconnect the engine wire protector from
the RH cylinder head.

23.

DISCONNECT ENGINE WIRE AND PROTECTOR
FROM RH SIDE

Remove the 3 nuts and 2 clamps, and disconnect the engine
wire protector from the RH cylinder head cover.