1991 LEXUS SC300 alternator

Stator (Drive End Frame)
1. INSPECT STATOR FOR OPEN CIRCUITUsing an ohmmeter, check that there is continuity between
the coil leads.
If there is no continuity, replace the drive end frame assem-
bly.
2. INSPECT STATOR FOR GROUND Using an ohmmeter, check that there is no continuity be-
tween the coil lead and drive end frame.
If there is continuity, replace the drive end frame assembly.
Brushes
INSPECT EXPOSED BRUSH LENGTHUsing a vernier caliper, measure the exposed brush length.
Standard exposed length: 10.5 mm (0.413 in.)
Minimum exposed length: 1.5 mm (0.059 in.)
If the exposed length is less than minimum, replace the brush
holder.
Rectifiers (Rectifier Holder)
1. INSPECT POSITIVE RECTIFIER(a) Using an ohmmeter, connect one tester probe to thepositive (+) terminal and the other to each rectifier
terminal.
(b) Reverse the polarity of the tester and repeat (a).
(c) Check that one shows continuity and the other shows no
continuity.
If continuity is not as specified, replace the rectifier holder.
2. INSPECT NEGATIVE RECTIFIER (a) Using an ohmmeter, connect one tester probe to each
negative (±) terminal and the other to each rectifier
terminal.
(b) Reverse the polarity of the tester probes and repeat (a).
(c) Check that one shows continuity and the other shows no
continuity.
If continuity is not as specified, replace the rectifier holder.
CH±14
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CHARGING SYSTEM Alternator
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Bearings
1. INSPECT FRONT BEARINGCheck that the bearing is not rough or worn.
2. IF NECESSARY, REPLACE FRONT BEARING (a) Remove the four screws, bearing retainer and bearing.
(b) Using a socket wrench and press, press out the bearing.
(c) Using SST and a press, press in a new bearing.
SST 09608±20012 (09608±00030)
(d) Install the bearing retainer with the four screws.
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CHARGING SYSTEM AlternatorCH±15
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3. INSPECT REAR BEARINGCheck that the bearing is not rough or worn.
4. IF NECESSARY, REPLACE REAR BEARING (a) Using SST, remove the bearing cover and bearing.
SST 09820±00021
NOTICE: Be careful not to damage the fan.
(b) Using SST and a press, press in a new bearing.
SST 09820±00030
(c) Using SST, push in the bearing cover.
SST 09285±76010
CH±16
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CHARGING SYSTEM Alternator
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ASSEMBLY OF ALTERNATOR
(See Components on page CH±10)
1. PLACE RECTIFIER END FRAME ON PULLEY
2. INSTALL ROTOR TO RECTIFIER END FRAME
3. INSTALL RECTIFIER END FRAME (a) Place the alternator washer on the rotor.
(b) Using a 29 mm socket wrench and press, slowly pressin the rectifier end frame.
(c) Install the four mounting nuts.
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CHARGING SYSTEM AlternatorCH±17
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4. INSTALL PULLEY(a) Install the pulley to the rotor shaft by tightening thepulley nut by hand.
(b) Hold SST (A) with a torque wrench, and tighten SST (B)
clockwise to the specified torque.
SST 09820±63010
Torque: 39 N Vm (400 kgf Vcm, 29 ft Vlbf)
(c) Check that SST (A) is secured to the pulley shaft.
(d) As shown in the illustration, mount SST (C) in a vise, and
install the alternator to SST (C).
(e) To torque the pulley nut, turn SST (A) in the direction shown in the illustration.
Torque: 110 N Vm (1,125 kgf Vcm, 81 ft Vlbf)
(f) Remove the alternator from SST (C).
(g) Turn SST (B) and remove SST (A and B).
5. INSTALL RECTIFIER HOLDER (a) Place the seal plate on the rectifier end frame.
(b) Install the four rubber insulators on the lead wires.
(c) Install the rectifier holder with the four screws.
CH±18
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6. INSTALL IC REGULATOR AND BRUSH HOLDER(a) Place the IC regulator together and brush holder on therectifier end frame.
NOTICE: Be careful of the holder installation direction.
(b) Install the five mounting screws until there is a clearance
of approx. 1 mm (0.04 in.) between the brush holder and
connector.
(c) Place the brush holder cover on the brush holder.
7. INSTALL REAR END COVER (a) Install the end cover with the three nuts.
(b) Install the terminal insulator with the nut.
8. CHECK THAT ROTOR ROTATES SMOOTHLY
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CHARGING SYSTEM AlternatorCH±19
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INSTALLATION OF ALTERNATOR
(See Components on page CH±9)
1. INSTALL ALTERNATOR (a) Install the alternator and A/T oil cooler bracket with the
bolt and nut.
Torque: 37 N Vm (380 kgf Vcm, 27 ft Vlbf)
(b) Connect the alternator connector.
(c) Connect the alternator wire with the nut and cap.
2. INSTALL DRIVE BELT Install the drive belt by turning the drive belt tensioner coun-
terclockwise.
HINT: The pulley bolt for the belt tensioner has a left±hand
thread.
3. CONNECT CABLE TO NEGATIVE TERMINAL OF BATTERY
4. PERFORM ON±VEHICLE INSPECTION (See steps 6 to 8 on pages CH±6 to 8)
5. INSTALL ENGINE UNDER COVER
CH±20
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15. DISCONNECT ENGINE WIRE CONNECTORS
16. DISCONNECT THEFT DETERRENT HORN CONNECTOR
17. DISCONNECT GROUND CABLE FROM BODY
18. DISCONNECT PS SOLENOID VALVE CONNECTOR
19. DISCONNECT WIRE CLAMP (FOR ALTERNATOR) FROMVSV (FOR EVAP SYSTEM)
(a) Remove the two bolts, and disconnect the VSV from the
RH cylinder head.
(b) Disconnect the wire clamp from the VSV bracket.
20. REMOVE ALTERNATOR (a) Disconnect the alternator connector.
(b) Remove the cap and nut, and disconnect the alternatorwire.
(c) Remove the mounting bolt and nut.
(d) Disconnect the A/T oil cooler pipe bracket.
(e) Remove the alternator.
21. D I S C O N N E C T P S T U B E S F R O M S U SPENSION
CROSSMEMBER
Remove the clamp bolt, and disconnect the PS tubes.
EM±122
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