LEXUS SC400 1991 Service Repair Manual
Manufacturer: LEXUS, Model Year: 1991, Model line: SC400, Model: LEXUS SC400 1991Pages: 4087, PDF Size: 75.75 MB
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(b) Check that the timing marks of the camshaft timingpulleys and timing belt rear plates aligned.
If not, turn the crankshaft one revolution (360 5).
27. REMOVE TIMING BELT TENSIONER HINT:
w(Re±using timing belt)
If the installation marks have disappeared, before re-
moving the timing belt, place new installation marks on
the timing belt to match the timing marks of the camshaft
timing pulleys, and place a new installation mark on the
timing belt to match the end of the hydraulic pump.
w (When replacing timing belt tensioner only)
To avoid meshing of the timing pulley and timing belt, se-
cure one of them with string. And place matchmarks on
the timing belt and RH camshaft timing pulley.
Alternately loosen the two bolts, and remove them, the ten-
sioner and dust boot.
28. DISCONNECT TIMING BELT FROM CAMSHAFT TIMING PULLEYS
(a) Using SST, loosen the tension between the LH and RHcamshaft timing pulleys by slightly turning the LH
camshaft timing pulley clockwise.
SST 09278±54012
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ENGINE MECHANICAL Timing BeltEM±41
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(b) Disconnect the timing belt from the camshaft timingpulleys.
29. REMOVE CAMSHAFT TIMING PULLEYS Using SST, remove the bolt, timing pulley. Remove the two
timing pulleys.
SST 09278±54012
30. REMOVE CRANKSHAFT PULLEY (a) Using SST, remove the pulley bolt.
SST 90213±70010 and 09330±00021
(b) Using SST, remove the pulley.
SST 09213±31021
31. REMOVE HYDRAULIC PUMP HINT (Re±using timing belt): Before removing the hydraulic
pump, using the crankshaft pulley bolt, turn the crankshaft
pulley and align the installation mark of the timing belt with the
end of the hydraulic pump.
EM±42
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(a) Disconnect the solenoid valve connector.
(b) Remove the two mounting bolts and two mounting nuts.
(c) Disconnect the engine speed sensor wire clamp.
(d) Remove the hydraulic pump.
32. REMOVE NO.1 TIMING BELT COVER Remove the four bolts, timing belt cover and gasket.
33. REMOVE TIMING BELT COVER SPACER Remove the cover spacer and gasket.
34. REMOVE TIMING BELT GUIDE (NO.1 CRANK ANGLE SENSOR PLATE)
35. REMOVE TIMING BELT HINT (Re±using timing belt): If the installation marks have
disappeared, place a new installation mark on the timing belt
to match the dot mark of the crankshaft timing pulley.
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36. REMOVE NO.2 IDLER PULLEYRemove the pulley bolt and idler pulley.
37. REMOVE NO.1 IDLER PULLEY Using a 10 mm hexagon wrench, remove the bolt, idler pulley
and plate washer.
38. REMOVE CRANKSHAFT TIMING PULLEY Using SST, remove the timing pulley.
SST 09213±60017 (09213±00050)
INSPECTION OF TIMING BELT
COMPONENTS
1. INSPECT TIMING BELTNOTICE:
w Do not bend, twist or turn the timing belt inside out.
w Do not allow the timing belt to come into contact with oil,
water or steam.
w Do not utilize timing belt tension when installing or
removing the mounting bolt of the camshaft timing
pulley.
If there are any defects as shown in the illustrations, check
the following points:
(a) Premature parting
w Check for proper installation.
w Check the timing cover gasket for damage and
proper installation.
EM±44
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(b) If the belt teeth are cracked or damaged, check to seeif either the camshaft is locked.
(c) If there is noticeable wear or cracks on the belt face, check to see if there are nicks on the side of the idler
pulley lock and water pump.
(d) If there is wear or damage on only one side of the belt, check the belt guide and the alignment of the each
pulley.
(e) If there is noticeable wear on the belt teeth, check timing belt cover for damage, correct gasket installation. and
the foreign material on the pulley teeth.
If necessary, replace the timing belt.
2. INSPECT IDLER PULLEYS Check the turning smoothness of the idler pulley.
If necessary, replace the idler pulley.
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3. INSPECT TIMING BELT TENSIONER(a) Visually check tensioner for oil leakage.
HINT: If there is only the faintest trace of oil on the seal on the
push rod side, the tensioner is all right.
If leakage is found, replace the tensioner.
(b) Hold the tensioner in both hands and push the push rodstrongly against the floor or wall to check that it doesn't
move.
If the push rod moves, replace the tensioner.
(c) Measure the protrusion of the push rod from the housing
end.
Protrusion: 10.5±11.5 mm (0.413±0.453 in.)
If the protrusion is not as specified, replace the tensioner.
INSTALLATION OF TIMING BELT
(See Components pages EM±33 and 34)
1. INSTALL CRANKSHAFT TIMING PULLEY (a) Align the pulley set key on the crankshaft with the keygroove of the timing pulley.
(b) Using SST and a hammer, tap in the timing pulley, facing
the flange side rearward.
SST 09223±46011
2. INSTALL NO. 1 IDLER PULLEY (a) Apply adhesive to two or three threads of the pulley boltend.
Adhesive: Part No. 08833±00080, THREE BOND 1344, LOCTITE
242 OR equivalent
(b) Using a 10 mm hexagon wrench, install the plate washer
and idler pulley with the pulley bolt. Torque the pulley
bolt.
Torque: 34 N Vm (350 kgf Vcm, 25 ft Vlbf)
(c) Check that the pulley bracket moves smoothly.
EM±46
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3. INSTALL NO. 2 IDLER PULLEY(a) Install the idler pulley with the pulley bolt. Torque thepulley bolt.
Torque: 34 N Vm (350 kgf Vcm, 25 ft Vlbf)
(b) Check that the idler pulley moves smoothly.
4. TEMPORARILY INSTALL TIMING BELT NOTICE: The engine should be cold.
(a) Using the crankshaft pulley bolt, turn the crankshaft andalign the timing marks of the crankshaft timing pulley
and oil pump body.
(b) Remove any oil or water on the crankshaft timing pulley,
No. 1 idler pulley and No. 2 idler pulley, and keep them
clean.
(c) Align the installation mark on the timing belt with the dot
mark of the crankshaft timing pulley.
(d) Install the timing belt on the crankshaft timing pulley, No.
1 idler pulley and No. 2 idler pulley.
5. INSTALL TIMING BELT GUIDE (NO. 1 CRANK ANGLE SENSOR PLATE)
Install the belt guide, facing the cup side forward.
6. INSTALL TIMING BELT COVER SPACER (a) Install the gasket to the spacer.
(b) Install the spacer.
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7. INSTALL NO.1 TIMING BELT COVER(a) Install the gasket to the timing belt cover.
(b) Install the timing belt cover with the four bolts.
8. INSTALL HYDRAULIC PUMP (a) Install the hydraulic pump and solenoid valve connectorclamp and engine speed sensor wire clamp with the two
bolts and two nuts.
Torque:
12 mm heads 16 N Vm (160 kgf Vcm, 12 ft Vlbf)
Others 30 N Vm (310 kgf Vcm, 22 ft Vlbf)
HINT: Each bolt length is indicated in the illustration.
Bolt length:
A 106 mm (4.17 in.) for 12 mm head
B 114 mm (4.49 in.) for 14 mm head
(b) Connect the solenoid valve connector.
9. INSTALL CRANKSHAFT PULLEY (a) Align the pulley set key on the crankshaft with the keygroove of the pulley.
(b) Using SST and a hammer, tap in the pulley.
SST 09223±46011
(c) Using SST, install and torque the pulley bolt.
SST 09213±70010 and 09330±00021
Torque: 245 N Vm (2,500 kgf Vcm, 181 ft Vlbf)
10. INSTALL RH CAMSHAFT TIMING PULLEY
(a) Align the knock pin on the camshaft with the knock pingroove of the timing pulley.
(b) Slide the timing pulley, facing the ºRº mark forward.
(c) Using SST, install and torque the pulley bolt.
SST 09278±54012
Torque: 108 N Vm (1,100 kgf Vcm, 80 ft Vlbf)
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11. INSTALL LH CAMSHAFT TIMING PULLEY(a) Align the knock pin on the camshaft with the knock pingroove of the timing pulley.
(b) Slide the timing pulley, facing the ºLº mark forward.
(c) Using SST, install and torque the pulley bolt.
SST 09278±54012
Torque: 108 N Vm (1,100 kgf Vcm, 80 ft Vlbf)
12. SET NO.1 CYLINDER TO TDC/COMPRESSION
(a) (Crankshaft Pulley Position)Turn the crankshaft pulley, and align its groove with the
ºOº timing mark of the No.1 timing belt cover.
(b) (Camshaft Timing Pulley Position) Using SST, t urn the camshaft timing pulley, and align the
timing marks of the camshaft timing pulley and timing
belt rear plate.
SST 09278±54012
13. INS TALL TIMING BE LT TO LH CAMS HAFT TIMING PULLEY
(a) Align the installation mark on the timing belt with the end
of the hydraulic pump.
(b) Remove any oil or water on the LH camshaft timing pulley, and keep it clean.
(c) Using SST, slightly turn the LH camshaft timing pulley
clockwise. Align the installation mark on the timing belt
with the timing mark of the camshaft timing pulley, and
hang the timing belt on the LH camshaft timing pulley.
SST 09278±54012
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(d) Using SST, align the timing marks of the LH camshaftpulley and timing belt rear plate.
SST 09278±54012
(e) Check that the timing belt has tension between the crankshaft timing pulley and LH camshaft timing pulley.
14. INSTALL TIMING BELT TO RH CAMSHAFT TIMING PULLEY
(a) Remove any oil or water on the RH camshaft timing andwater pump pulley, and keep them clean.
(b) Using SST, slightly turn the RH camshaft timing pulley clockwise. Align the installation mark on the timing belt
with the timing mark of the camshaft timing pulley, and
hang the timing belt on the RH camshaft timing pulley.
SST 09278±54012
(c) Using SST, align the timing marks of the RH camshaft pulley and timing belt rear plate.
SST 09278±54012
(d) Check that the timing belt has tension between the RH
camshaft timing pulley and LH camshaft pulley.
15. SET TIMING BELT TENSIONER (a) Using a press, slowly press in the push rod using981±9,807 N (100±1,000 kgf, 220±2,205 lbf) of
pressure.
(b) Align the holes of the push rod and housing, pass a 1.27
mm hexagon wrench through the holes to keep the
setting position of the push rod.
(c) Release the press.
(d) Install the dust boot to the tensioner.
EM±50
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