How to Adjust Valve Clearance on Lexus/Toyota 1UZFE Engines (Pre-1998)

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SET NO.1 CYLINDER TO TDC/COMPRESSION

(a) Turn the crankshaft pulley, and align its
groove with the

timing mark îOî 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 one revolution (360)
and align the

mark as above.

 

 





INSPECT VALVE CLEARANCE

(a) Check only those valves indicated in the
figure.

Using a
feeler gauge, measure the clearance

between the valve lifter and camshaft.

Record out
of specification valve clearance

measurements. They will be used later to

determine the required replacement adjusting

shim.

Valve clearance (Cold):

Intake 0.15ñ0.25 mm (0.006ñ0.010 in.)

Exhaust 0.25ñ0.35 mm (0.010ñ0.014 in.)

(b) Turn the crankshaft one revolution (360),
and align the

mark as above. (See procedure step 5 (a))

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

Measure the valve clearance.

 


 

 



INSPECT VALVE CLEARANCE

(a) Check only those valves indicated in the
figure.

Using a
feeler gauge, measure the clearance

between the valve lifter and camshaft.

Record out
of specification valve clearance

measurements. They will be used later to

determine the required replacement adjusting

shim.

Valve clearance (Cold):

Intake 0.15ñ0.25 mm (0.006ñ0.010 in.)

Exhaust 0.25ñ0.35 mm (0.010ñ0.014 in.)

(b) Turn the crankshaft one revolution (360),
and align the

mark as above. (See procedure step 5 (a))

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

Measure the valve clearance.



Please refer to the sheets for shim

thickness reference!
 



Intake Shim Thickness



Exhaust Shim Thickness



ADJUST VALVE CLEARANCE

(a) Remove the adjusting shim.

Turn the
crankshaft to position the cam lobe of the

camshaft on the adjusting valve upward.

Press down
the valve lifter with SST (A), and place

SST (B) between the camshaft and valve lifter

flange. Remove SST (A).

SST 09248ñ55011

Using
compressed air and magnetic finger, remove

the adjusting shim by blowing air into the shim
hole.

(b) Determine the replacement adjusting shim
size

following the Formula or Charts:

Using a
micrometer, measure the thickness of the

removed shim.

Calculate
the thickness of a new shim so that the

valve clearance comes within specified value.

T ………. Thickness of used shim

A ………. Measured valve clearance

N ………. Thickness of new shim

Intake N = T + (Añ0.20 mm (0.008 in.))

Exhaust N = T + (Añ0.30 mm (0.012 in.))

Select a new shim
with a thickness as close as

possible to the calculated values.

HINT: Shims are available in seventeen sizes of
0.05 mm

(0.0020 in.), from 2.50 mm (0.0984 in.) to 3.30
mm (0.1299 in.).

(c) Install a new adjusting shim.


Place a new
adjusting shim on the valve lifter.

Press down
the valve lifter with SST (A), and

remove SST (B).

SST 09248ñ55011

(d) Recheck the valve clearance.


 

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