Lexus SC300 / Lexus SC400. Manual - part 438

(d)  Using a plastic–faced hammer, lightly tap the valve stem

tip to assure proper fit.

4. 

INSTALL VALVE LIFTERS AND SHIMS
(a)  Install the valve lifter and shim.
(b)  Check that the valve lifter rotates smoothly by hand.

INSTALLATION OF CYLINDER HEAD

(See Components on pages EM–34 and 35)

1. 

INSTALL CYLINDER HEAD

A.

Place cylinder head on cylinder block
(a)  Place a new cylinder head gasket in position on the

cylinder block.

NOTICE: Be sure to install it correctly.

(b)  Place the cylinder head in position on the cylinder head

gasket and connect the heater water hose to the union.

B.

Install cylinder head bolts
HINT:

•

The cylinder head bolts are tightened in two progressive
steps (steps (c) and (f)).

•

If any of bolts break or deform, replace them.

(a) Apply 

a 

light coat of engine oil on the threads and under

the heads of the cylinder head bolts.

(b)  Install the 14 plate washers to each cylinder head bolt.
(c)  First, using a 10 mm bi–hexagon wrench, uniformly

tighten the cylinder head bolts in several passes in the
sequence shown.

Torque:

34 N

⋅

m (350 kgf

⋅

cm, 25 ft

⋅

lbf)

If any one of the bolts does not meet the torque specification,
replace the bolt.

EM–54

–

ENGINE MECHANICAL

Cylinder Head

(d)  Mark the front of the cylinder head bolt head with paint.

(e)  Second retighten the cylinder head bolts 90

 in the

numerical order shown above.

(f) 

Third retighten cylinder head bolts by an additional 90

.

(g)  Check that the painted mark is now turned to the rear.

2. INSTALL 

CAMSHAFTS

(a)  Apply engine oil to the thrust portion of the camshaft.
(b)  Place the camshaft on the cylinder head with the cam

lobe facing up as shown.

(c)  Place the No.3 and No.7 bearing caps in their proper

location.

(d) Apply 

a 

light coat of engine oil on the threads and under

the heads of the bearing cap bolts.

(e)  Temporarily tighten these bearing cap bolts uniformly

and alternately in several passes until the bearing caps
are snug with the cylinder head.

–

ENGINE MECHANICAL

Cylinder Head

EM–55

(f)  Apply MP grease to a new camshaft oil seal lip.

(g)  Install the oil seal to the camshaft.

(h)  Clean the installed surfaces of the No. 1 bearing cap

and cylinder head with cleaner.

(i) 

Apply seal packing to the No. 1 bearing cap as shown.

Seal packing:

Part No. 08826–00080 or equivalent

(j) 

Install other bearing caps in their proper locations.

(k) Apply 

a 

light coat of engine oil on the threads and under

the heads of the bearing cap bolts.

(l) 

Install and uniformly tighten the 14 bearing cap bolts on
one side in several passes in the sequence shown.

Torque: 20 

N

⋅

m (200 kgf

⋅

cm, 14 ft

⋅

lbf)

EM–56

–

ENGINE MECHANICAL

Cylinder Head

(m)  Using SST, push the oil seal as far as it would go.
SST 09316–60010 (09316–00010, 09316–00050)

(n)  Rotate the camshaft with a wrench at the hexagon

position, bring the forward straight pin up.

(o)  Loosen the two bearing cap bolts as shown, until they

can be turned by hand; retighten in several passes.

Torque:

20 N

⋅

m (200 kgf

⋅

cm, 14 ft

⋅

lbf)

(p)  Turn the camshaft 1/3 of revolution.
(q)  Loosen the two bearing cap bolts as shown, until they

can be turned by hand; retighten in several passes.

Torque:

20 N

⋅

m (200 kgf

⋅

cm, 14 ft

⋅

lbf)

(r)  Turn the camshaft a further 1/3 of a revolution.
(s)  Loosen the two bearing cap bolts as shown, until they

can be turned by hand; retighten is several passes.

Torque:

20 N

⋅

m (200 kgf

⋅

cm, 14 ft

⋅

lbf)

3. 

CHECK AND ADJUST VALVE CLEARANCE
(See steps 12 and 13 on pages EM–12 to 16)
Turn the camshaft, and position the cam lobe upward, check
and adjust the valve clearance.

Valve clearance:

Intake 

0.15–0.25 mm (0.006–0.010 in.)

Exhaust 

0.25–0.35 mm (0.010–0.014 in.)

–

ENGINE MECHANICAL

Cylinder Head

EM–57