Page 1289 of 1807

Z02413
Z00052
Z00054
44.5°
EM0181
Margin Thickness
- ENGINE MECHANICAL (2JZ-GTE)CYLINDER HEAD
EM-37
1142 Author: Date:
1997 SUPRA (RM502U)
9. 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.)
(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 0.025 - 0.060 mm (0.0010 - 0.0024 in.)
Exhaust 0.030 - 0.065 mm (0.0012 - 0.0026 in.)
Maximum oil clearance:
Intake 0.08 mm (0.0031 in.)
Exhaust 0.10 mm (0.0039 in.)
If the clearance is greater than maximum, replace the valve and
guide bushing.
10. 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: 44.5°
(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.
Page 1290 of 1807

EM2534
Overall Length
EM0255
P02127
45°
Carbide
Cutter
Z00373
Width
P03966
45°
15°
Width EM-38
- ENGINE MECHANICAL (2JZ-GTE)CYLINDER HEAD
1143 Author: Date:
1997 SUPRA (RM502U)
(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.
11. 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:
If blue appears 360° around the face, the valve is
concentric. If not, replace the valve.
If blue appears 360° around the valve seat, the
guide and face are concentric. If not, resurface the
seat.
Check 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:
If the seating is too high on the valve face, use 15°
and 45° cutters to correct the seat.
Page 1291 of 1807

Z02456
45° 75°
Width
P02126
Z02457
Deviation
EM0801
EM0281
- ENGINE MECHANICAL (2JZ-GTE)CYLINDER HEAD
EM-39
1144 Author: Date:
1997 SUPRA (RM502U)
If the seating is too low on the valve face, use 75°
and 45° cutters to correct the seat.
(d) Hand-lap the valve and valve seat with an abrasive com-
pound.
(e) After hand-lapping, clean the valve and valve seat.
12. 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: 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.
Page 1292 of 1807

P04463
EM2011
EM2538
P02141
P02360
Plastigage EM-40
- ENGINE MECHANICAL (2JZ-GTE)CYLINDER HEAD
1145 Author: Date:
1997 SUPRA (RM502U)
13. 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 (0.0031 in.)
If the circle runout is greater than maximum, replace the cam-
shaft.
14. 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.
15. 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.
16. INSPECT CAMSHAFT BEARINGS
Check the bearings for flaking and scoring.
If the bearings are damaged, replace the bearing caps and cyl-
inder head as a set.
17. 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 jour-
nals.
Page 1293 of 1807

P02166
P02268
P02167
P02264
- ENGINE MECHANICAL (2JZ-GTE)CYLINDER HEAD
EM-41
1146 Author: Date:
1997 SUPRA (RM502U)
(d) Install the bearing caps (See page EM-47).
Torque: 20 N´m (200 kgf´cm, 14 ft´lbf)
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.
18. INSPECT CAMSHAFT THRUST CLEARANCE
(a) Install the camshafts (See page EM-47).
(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 cylinder
head as a set.
19. 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.)
Page 1294 of 1807

EM2196
A02166
P12544
P12281P12281
A02828
About
50 mm
Compressed
Thread
EM-42
- ENGINE MECHANICAL (2JZ-GTE)CYLINDER HEAD
1147 Author: Date:
1997 SUPRA (RM502U)
(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.
20. INSPECT AIR INTAKE CHAMBER
Using a precision straight edge and feeler gauge, measure the
surfaces contacting the intake manifold for warpage.
Maximum warpage: 0.15 mm (0.0059 in.)
If warpage is greater than maximum, replace the chamber.
21. INSPECT INTAKE MANIFOLD
Using a precision straight edge and feeler gauge, measure the
surfaces contacting the cylinder head and air intake chamber
for warpage.
Maximum warpage: 0.15 mm (0.0059 in.)
If warpage is greater than maximum, replace the manifold.
22. INSPECT EXHAUST MANIFOLD
Using a precision straight edge and feeler gauge, measure the
surfaces contacting the cylinder head for warpage.
Maximum warpage: 0.80 mm (0.0315 in.)
If warpage is greater than maximum, replace the manifold.
23. INSPECT CYLINDER HEAD BOLTS
Using a vernier caliper, measure the thread outside diameter of
the bolt.
Standard outside diameter:
10.8 - 11.0 mm (0.425 - 0.433 in.)
Minimum outside diameter: 10.7 mm (0.421 in.)
If the diameter is less than minimum, replace the bolt.
Page 1295 of 1807

EM0AK-02
S00401
SST
P02265
Z16742
SST
P04791
38.5 mm
(1.516 in.) Intake Exhaust
40.5 mm
(1.594 in.)
- ENGINE MECHANICAL (2JZ-GTE)CYLINDER HEAD
EM-43
1148 Author: Date:
1997 SUPRA (RM502U)
REPLACEMENT
1. REPLACE VALVE GUIDE BUSHINGS
(a) Using SST and a hammer, tap out the guide bushing.
SST 09201-10000 (09201-01060),
09950-70010 (09951-07100)
(b) Using a caliper gauge, measure the bushing bore diame-
ter of the cylinder head.
(c) Select a new guide bushing (STD or O/S 0.05).
Both intake and exhaust
Bushing bore diameter mm (in.)Bushing size
10.985 - 11.006 (0.4350 - 0.4333)Use STD
11.035 - 11.056 (0.4344 - 0.4353)Used 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 follow-
ing 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.
(d) Using SST and a hammer, tap in a new guide bushing to
the specified protrusion height.
SST 09201-10000 (09201-01060),
09950-70010 (09951-07100)
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.
Page 1296 of 1807
Z02415
Sharp
6 mm
Reamer EM-44
- ENGINE MECHANICAL (2JZ-GTE)CYLINDER HEAD
1149 Author: Date:
1997 SUPRA (RM502U)
(e) Using a sharp 6 mm reamer, ream the guide bushing to
obtain the standard specified clearance (See page
EM-35) between the guide bushing and valve stem.