1995 TOYOTA SUPRA engine

(b) Using a gasket scraper, remove all the gasket material from
the top surface of the cylinder block.
(c) Using compressed air, blow carbon and oil from the bolt
holes.
CAUTION: Protect your eyes when using high pressure com-
pressed air.
2. CLEAN CYLINDER HEAD
A. Remove gasket material
Using a gasket scraper, remove all the gasket material from
the cylinder block surface.
NOTICE: Be careful not to scratch the cylinder block contact
surface.
B. Clean combustion chambers
Using a wire brush, remove all the carbon from the combus-
tion chambers.
NOTICE: Be careful not to scratch the cylinder block contact
surface.
C. Clean valve guide bushings
Using a valve guide bushing brush and solvent, clean all the
guide bushings.
D. Clean cylinder head
Using a soft brush and solvent, thoroughly clean the cylinder
head.
± ENGINEENGINE MECHANICALEG±51

3. INSPECT CYLINDER HEAD
A. Inspect for flatness
Using precision straight edge and feeler gauge, measure the
surfaces contacting the cylinder block, intake and exhaust
manifolds for warpage.
Maximum warpage:
0.10 mm (0.0039 in.)
If warpage is greater than maximum, replace the cylinder
head.
B. Inspect for cracks
Using a dye penetrant, check the combustion chamber, in-
take ports, exhaust ports and cylinder block surface for
cracks.
If cracked, replace the cylinder head.
4. CLEAN VALVES
(a) Using a gasket scraper, chip off any carbon from the valve
head.
(b) Using a wire brush, throughly clean the valve.
5. INSPECT VALVE STEMS AND GUIDE BUSHINGS
(a) Using a caliper gauge, measure the inside diameter of the
guide bushing.
Bushing inside diameter:
6.010±6.030 mm (0.2366±0.2374 in.)
EG±52± ENGINEENGINE MECHANICAL

Bushing bore diameter
mm (in.)
10.985±11.006 mm
(0.4325±0.4333 in.)Both intake and exhaust
11.035±11.056 mm
(0.4344±0.4353 in.)Bushing
size
Use STD
Use O/S
0.05
(b) Using a micrometer, measure the diameter of the valve stem.
Valve stem diameter:
Intake
5.970±5.985 mm (0.2350±0.2356 in.)
Exhaust
5.965±5.980 mm (0.2348±0.2354 in.)
(c) Subtract the valve stem diameter measurement from the
guide bushing inside diameter measurement.
Standard oil clearance:
Intake
.025±0.060 mm (0.0010±0.0024 in.)
Exhaust
.030±0.065 mm (0.0012±0.0026 in.)
Maximum oil clearance:
Intake
.08 mm (0.0031 in.)
Exhaust
.10 mm (0.0039 in.)
If the clearance is greater than maximum, replace the valve
and guide bushing.
6. IF NECESSARY, REPLACE VALVE GUIDE BUSHINGS
(a) Using SST and a hammer, tap out the guide bushing.
SST 09201±10000 (09201±01060).
09608±30022 (09608±05010)
(b) Using a caliper gauge, measure the bushing bore diameter
of the cylinder head.
(c) Select a new guide bushing (STD or O/S 0.05).
If the bushing bore diameter of the cylinder head is greater
than 11.006 mm (0.4333 in.), machine the bushing bore to
the following dimension:
11.035±11.056 mm (0.4344±0.4353 in.)
If the bushing bore diameter of the cylinder head is greater
than 11.056 mm (0.4353 in.), replace the cylinder head.
± ENGINEENGINE MECHANICALEG±53

(d) Using SST and a hammer, tap in a new guide bushing to the
specified protrusion height.
SST 09201±10000 (09201±01060), 09608±30022
(09608±05010)
Protrusion height:
Intake
12.3±12.7 mm (0.484±0.500 in.)
Exhaust
11.4±11.8 mm (0.449±0.465 in.)
HINT: Different bushings are used for the intake and exhaust.
(e) Using a sharp 6 mm reamer, ream the guide bushing to obtain
the standard specified clearance (See step 6) between the
guide bushing and valve stem.
7. INSPECT AND GRIND VALVES
(a) Grind the valve enough to remove pits and carbon.
(b) Check that the valve is ground to the correct valve face angle.
Valve face angle:
44.55
(c) Check the valve head margin thickness.
Standard margin thickness:
0.8±1.2 mm (0.031±0.047 in.)
Minimum margin thickness:
0.5 mm (0.020 in.)
If the margin thickness is less than minimum, replace the
valve. EG±54
± ENGINEENGINE MECHANICAL

(d) Check the valve overall length.
Standard overall length:
Intake
98.29±98.79 mm (3.8697±3.8894 in.)
Exhaust
98.84±99.34 mm (3.8913±3.9110 in.)
Minimum overall length:
Intake
98.19 mm (3.8657 in.)
Exhaust
98.74 mm (3.8874 in.)
If the overall length is less than minimum, replace the valve.
(e) Check the surface of the valve stem tip for wear.
If the valve stem tip is worn, resurface the tip with a grinder
or replace the valve.
NOTICE: Do not grind off more than the minimum overall
length.
8. INSPECT AND CLEAN VALVE SEATS
(a) Using a 45° carbide cutter, resurface the valve seats.
Remove only enough metal to clean the seats.
(b) Check the valve seating position.
Apply a thin coat of prussian blue (or white lead) to the valve
face. Lightly press the valve against the seat. Do not rotate
the valve.
(c) Check the valve face and seat for the following:
wIf blue appears 360° around the face, the valve is
concentric. If not, replace the valve.
wIf blue appears 360° around the valve seat, the guide
and face are concentric. If not, resurface the seat.
wCheck that the seat contact is in the middle of the valve
face with the following width:
Intake
1.0±1.4 mm (0.039±0.055 in.)
Exhaust
1.2±1.6 mm (0.047±0.063 in.)
If not, correct the valve seats as follows:
wIf the seating is too high on the valve face, use 15° and
45° cutters to correct the seat.
± ENGINEENGINE MECHANICALEG±55

wIf the seating is too low on the valve face, use 60° and
45° cutters to correct the seat.
(d) Hand±lap the valve and valve seat with an abrasive
compound.
(e) After hand±lapping, clean the valve and valve seat.
9. INSPECT VALVE SPRINGS
(a) Using a steel square, measure the deviation of the valve
spring.
Maximum deviation:
2.0 mm (0.079 in.)
If deviation is greater than maximum, replace the valve
spring.
(b) Using vernier calipers, measure the free length of the valve
spring.
Free length:
Blue painted mark
41.74 mm (1.6433 in.)
Yellow painted mark
41.70 mm (1.6417 in.)
If the free length is not as specified, replace the valve spring.
(c) Using a spring tester, measure the tension of the valve spring
at the specified installed length.
Installed tension:
186±206 N (19.0±21.0 kgf, 42±46 lbf) at 34.5 mm
(1.358 in.)
If the installed tension is not as specified, replace the valve
spring. EG±56
± ENGINEENGINE MECHANICAL

10. INSPECT CAMSHAFTS AND BEARINGS
A. Inspect camshaft for runout
(a) Place the camshaft on V±blocks.
(b) Using a dial indicator, measure the circle runout at the center
journal.
Maximum circle runout:
0.08 mm ª(0.0031 in.)
If the circle runout is greater than maximum, replace the cam-
shaft.
B. Inspect cam lobes
Using a micrometer, measure the cam lobe height.
Standard cam lobe height:
Intake
44.570±44.670 mm (1.7547±1.7587 in.)
Exhaust
44.770±44.870 mm (1.7626±1.7665 in.)
Maximum cam lobe height:
Intake
44.42 mm (1.7488 in.)
Exhaust
44.62 mm (1.7567 in.)
If the cam lobe height is less than minimum, replace the cam-
shaft.
C. Inspect camshaft journals
Using a micrometer, measure the journal diameter.
Journal diameter:
28.949±28.965 mm (1.1397±1.1404 in.)
If the journal diameter is not as specified, check the oil clear-
ance.
D. Inspect camshaft bearings
Check the bearings for flaking and scoring.
If the bearings are damaged, replace the bearing caps and
cylinder head as a set.
E. Inspect camshaft journal oil clearance
(a) Clean the bearing caps and camshaft journals.
(b) Place the camshafts on the cylinder head.
(c) Lay a strip of Plastigage across each of the camshaft
journals.
± ENGINEENGINE MECHANICALEG±57

(d) Install the bearing caps.
(See step 2 in cylinder head installation (2JZ±GE))
Torque: 20 NVm (200 kgfVcm, 14 ftVlbf)
NOTICE: Do not turn the camshaft.
(e) Remove the bearing caps.
(f) Measure the Plastigage at its widest point.
Standard oil clearance:
0.035±0.072 mm (0.0014±0.0028 in.)
Maximum oil clearance:
0.10 mm (0.0039 in.)
If the oil clearance is greater than maximum, replace the cam-
shaft. If necessary, replace the bearing caps and cylinder
head as a set.
(g) Completely remove the Plastigage.
F. Inspect camshaft thrust clearance
(a) Install the camshafts.
(See step 2 in cylinder head installation (2JZ±GE))
(b) Using a dial indicator, measure the thrust clearance while
moving the camshaft back and forth.
Standard thrust clearance:
0.080±0.190 mm (0.0031±0.0075 in.)
Maximum thrust clearance:
0.30 mm (0.0118 in.)
If the thrust clearance is greater than maximum, replace the
camshaft. If necessary, replace the bearing caps and cylin-
der head as a set.
11. INSPECT VALVE LIFTERS AND LIFTER BORES
(a) Using a caliper gauge, measure the lifter bore diameter of the
cylinder head.
Lifter bore diameter:
31.000±31.016 mm (1.2205±1.2211 in.)
(b) Using a micrometer, measure the lifter diameter.
Lifter diameter:
30.966±30.976 mm (1.2191±1.2195 in.)
(c) Subtract the lifter diameter measurement from the lifter bore
diameter measurement.
Standard oil clearance:
0.024±0.050 mm (0.0009±0.0020 in.)
Maximum oil clearance:
0.07 mm (0.0028 in.)
If the oil clearance is greater than maximum, replace the lifter.
If necessary, replace the cylinder head. EG±58
± ENGINEENGINE MECHANICAL