Last Modified: 11-29-2007 1.6 N Service Category: Engine/Hybrid System Section: Engine Mechanical Model Year: 2008 Model: Sequoia Doc ID: RM000002BOV00AX Title: 2UZ-FE ENGINE MECHANICAL: VALVE CLEARANCE: ADJUSTMENT (2008 Sequoia) ADJUSTMENT 1. DISCHARGE FUEL SYSTEM PRESSURE 2. REMOVE THROTTLE BODY COVER SUB-ASSEMBLY 3. REMOVE AIR CLEANER HOSE ASSEMBLY 4. REMOVE AIR SWITCHING VALVE ASSEMBLY (a) Remove the air switching valve assembly . 5. REMOVE IGNITION COIL ASSEMBLY 6. REMOVE FAN AND GENERATOR V BELT 7. REMOVE NO. 3 TIMING BELT COVER SUB-ASSEMBLY LH 8. REMOVE NO. 3 TIMING BELT COVER SUB-ASSEMBLY RH 9. REMOVE CYLINDER HEAD COVER SUB-ASSEMBLY 10. REMOVE CYLINDER HEAD COVER SUB-ASSEMBLY LH 11. SET NO. 1 CYLINDER TO TDC/COMPRESSION (a) Turn the crankshaft pulley to align its notch with timing mark "0" of the No. 1 timing belt cover. (b) Check that the timing marks of the camshaft timing pulleys and timing belt rear plates are aligned. If not, turn the crankshaft 1 complete revolution (360°) and align the marks as above. 12. INSPECT VALVE CLEARANCE (a) Check only the valves indicated. (1) Using a feeler gauge, measure the clearance between the valve lifter and camshaft. Standard Valve Clearance (Cold): Item Specified Condition Intake 0.15 to 0.25 mm (0.00591 to 0.00984 in.) Exhaust 0.25 to 0.35 mm (0.00984 to 0.0138 in.) (2) Record the out-of-specification valve clearance measurements. They will be used later to determine the required replacement adjusting shim.

(b) Turn the crankshaft 1 complete revolution (360°) and align the camshaft timing marks.

(c) Check only the valves indicated in the illustration.

(1) Using a feeler gauge, measure the clearance between the valve lifter and camshaft.

Standard Valve Clearance (Cold):

(2) Record the out-of-specification valve clearance measurements. They will be used later to determine the required replacement adjusting shim.

(a) Remove the timing belt .

(b) Remove the camshaft .

(c) Remove the valve lifter and adjusting shim.

NOTICE:

Be careful not to drop the adjusting shim into the cylinder head.

(d) Determine the replacement adjusting shim size according to the formula or charts below. (1) Using a micrometer, measure the thickness of the removed shim. (2) Calculate the thickness of a new shim so that the valve clearance comes within the specified value. T: Thickness of removed shim A: Measured valve clearance N: Thickness of new shim Intake: N = T + (A - 0.20 mm (0.00787 in.)) Exhaust: N = T + (A - 0.30 mm (0.0118 in.)) (3) Select a new shim with a thickness as close as possible to the calculated value. HINT: Shims are available in 41 increments of 0.020 mm (0.000787 in.), from 2.00 mm (0.0787 in.) to 2.80 mm (0.1102 in.). Refer to the Adjusting Shim Selection Chart. Intake valve clearance (Cold): 0.15 to 0.25 mm (0.00591 to 0.00984 in.) EXAMPLE: The 2.300 mm (0.0906 in.) shim is installed, and the measured clearance is 0.440 mm (0.0173 in.). Replace the 2.300 mm (0.0906 in.) shim with a No. 54 shim. New Shim Thickness: Shim No. Thickness Shim No. Thickness Shim No. Thickness 00 2.000 mm (0.0787 in.) 28 2.280 mm (0.0898 in.) 56 2.560 mm (0.1008 in.) 02 2.020 mm (0.0795 in.) 30 2.300 mm (0.0906 in.) 58 2.580 mm (0.1016 in.) 04 2.040 mm (0.0803 in.) 32 2.320 mm (0.0913 in.) 60 2.600 mm (0.1024 in.) 06 2.060 mm (0.0811 in.) 34 2.340 mm (0.0921 in.) 62 2.620 mm (0.1031 in.) 08 2.080 mm (0.0819 in.) 36 2.360 mm (0.0929 in.) 64 2.640 mm (0.1039 in.) 10 2.100 mm (0.0827 in.) 38 2.380 mm (0.0937 in.) 66 2.660 mm (0.1047 in.) 12 2.120 mm (0.0835 in.) 40 2.400 mm (0.0945 in.) 68 2.680 mm (0.1055 in.) 14 2.140 mm (0.0843 in.) 42 2.420 mm (0.0953 in.) 70 2.700 mm (0.1063 in.) 16 2.160 mm (0.0850 in.) 44 2.440 mm (0.0961 in.) 72 2.720 mm (0.1071 in.) 18 2.180 mm (0.0858 in.) 46 2.460 mm (0.0969 in.) 74 2.740 mm (0.1079 in.) 20 2.200 mm (0.0866 in.) 48 2.480 mm (0.0976 in.) 76 2.760 mm (0.1087 in.) 22 2.220 mm (0.0874 in.) 50 2.500 mm (0.0984 in.) 78 2.780 mm (0.1094 in.) 24 2.240 mm (0.0882 in.) 52 2.520 mm (0.0992 in.) 80 2.800 mm (0.1102 in.) 26 2.260 mm (0.0890 in.) 54 2.540 mm (0.1000 in.) - -

Exhaust valve clearance (Cold):

0.25 to 0.35 mm (0.00984 to 0.0138 in.)

EXAMPLE:

The 2.300 mm (0.0906 in.) shim is installed, and the measured clearance is 0.440 mm (0.0173 in.). Replace the 2.300 mm (0.0906 in.) shim with a No. 44 shim.

New Shim Thickness:

(e) Place a new adjusting shim on the valve.

(f) Place the valve lifter.

(g) Install the camshaft .

(h) Install the timing belt .

(i) Check the valve clearance.

If the result is not as specified, adjust the valve clearance.

14. INSTALL CYLINDER HEAD COVER SUB-ASSEMBLY LH

15. INSTALL CYLINDER HEAD COVER SUB-ASSEMBLY

16. INSTALL NO. 3 TIMING BELT COVER SUB-ASSEMBLY RH

17. INSTALL NO. 3 TIMING BELT COVER SUB-ASSEMBLY LH

18. INSTALL IGNITION COIL ASSEMBLY

Install the air switching valve assembly .

20. INSTALL FAN AND GENERATOR V BELT

21. INSTALL AIR CLEANER HOSE ASSEMBLY

22. INSTALL THROTTLE BODY COVER SUB-ASSEMBLY

23. INSPECT FOR OIL LEAK