Lexus LS400 (2000 year). Manual — part 76

EM6525

EM0227

EM6347

P20662

–

ENGINE MECHANICAL

CYLINDER BLOCK

EM–105

1287

14.

INSPECT PISTON PIN OIL CLEARANCE

(a)

Using a caliper gauge, measure the inside diameter of the
connecting rod bushing.
Bushing inside diameter:
22.005 – 22.014 mm (0.8663 – 0.8667 in.)

(b)

Using a micrometer, measure the piston pin diameter.
Piston pin diameter:
21.997 – 22.006 mm (0.8660 – 0.8664 in.)

(c)

Subtract the piston pin diameter measurement from the
bushing inside diameter measurement.
Oil clearance:

Standard

0.005 – 0.011 mm (0.0002 – 0.0004 in.)

Maximum

0.05 mm (0.0020 in.)

If the oil clearance is greater than maximum, replace the bush-
ing. If necessary, replace the piston and piston pin as a set.

15.

INSPECT CONNECTING ROD BOLTS

Using vernier calipers, measure the tension portion of the con-
necting rod bolt.

Diameter:

Standard

7.200 – 7.300 mm (0.2835 – 0.2874 in.)

Minimum

7.00 mm (0.2756 in.)

If the diameter is less than minimum, replace the bolt.

16.

INSPECT CRANKSHAFT FOR CIRCLE RUNOUT

(a)

Place the crankshaft on V–blocks.

(b)

Using a dial indicator, measure the circle runout at the
center journal.
Maximum circle runout: 0.08 mm (0.0031 in.)

If the circle runout is greater than maximum, replace the crank-
shaft.

Z14536

EM–106

–

ENGINE MECHANICAL

CYLINDER BLOCK

1288

17.

INSPECT MAIN JOURNALS AND CRANK PINS

(a)

Using a micrometer, measure the diameter of each main
journal and crank pin.
Diameter:

Main journal

66.988 – 67.000mm (2.6373 – 2.6378 in.)

Crank pin

51.982 – 52.000 mm (2.0465 – 2.0472 in.)

If the diameter is not as specified, check the oil clearance (See
disassembly). If necessary, replace the crankshaft.
(b)

Check each main journal and crank pin for taper and out–
of–round as shown.
Maximum taper and out–of–round:
0.02 mm (0.0008 in.)

If the taper and out–of–round is greater than maximum, replace
the crankshaft.

EM09K–02

–

ENGINE MECHANICAL

IDLE SPEED

EM–11

1193

IDLE SPEED

INSPECTION

1.

INITIAL CONDITIONS

(a)

Engine at normal operating temperature

(b)

Air cleaner installed

(c)

All pipes and hoses of air induction system connected

(d)

All accessories switched OFF

(e)

All vacuum lines properly connected

HINT:
All vacuum hoses should be properly connected.
(f)

SFI system wiring connectors fully plugged

(g)

Ignition timing set correctly

(h)

Transmission in neutral position

(i)

Air conditioning switched OFF

2.

CONNECT LEXUS HAND–HELD TESTER OR OBD II SCAN TOOL (See page

EM–9

)

3.

INSPECT IDLE SPEED

(a)

Race the engine speed at 2,500 rpm for approx. 90 seconds.

(b)

Check the idle speed.
Idle speed: 750

±

50 rpm

If the idle speed is not as specified, check the air intake system.
4.

DISCONNECT LEXUS HAND–HELD TESTER OR
OBD II SCAN TOOL

EM0A3–02

A02085

A02086

60

°

C

A02087

A02088

A02089

Front Mark
(2 Cavities)

Front Mark
(1 Cavity)

Outside Mark

LH Piston

RH Piston

Outside
Mark

A01908

EM–110

–

ENGINE MECHANICAL

CYLINDER BLOCK

1292

REASSEMBLY

HINT:

Thoroughly clean all parts to be assembled.

Before installing the parts, apply new engine oil to all slid-
ing and rotating surfaces.

Replace all gaskets, O–rings and oil seals with new parts.

1.

ASSEMBLE PISTON AND CONNECTING ROD

(a)

Using a small screwdriver, install a new snap ring on one
side of the piston pin hole.

(b)

Gradually heat the piston to about 60

°

C (140

°

F).

(c)

Coat the piston pin with engine oil.

(d)

Position the piston front mark with respect to the outside
mark on the connecting rod as shown in the diagram.

NOTICE:
The installation directions of the piston and connecting rod
are different for the RH and LH banks. The RH piston is
marked with ”R”, the LH piston with ”L”.
(e)

Align the piston pin holes of the piston and connecting
rod, and push in the piston pin with your thumb.

(f)

Using a small screwdriver, install a new snap ring on the
other side of the piston pin hole.