LEXUS SC400 1991 Service Repair Manual

(i) Remove the bolt holding the engine wire clamp to theheater water valve bracket.
(j) Remove the two bolts holding the engine wire clamp to the body.
(k) Pull out the engine wire from the cabin.
28. REMOVE FRONT EXHAUST PIPE (a) Disconnect the grommet from the floor, and disconnectthe sub±oxygen sensor from the exhaust pipe.
Disconnect the two sub±oxygen sensors.
(b) Remove the four bolts holding the front exhaust pipe to the transmission.
(c) Remove the two bolts and nuts holding the front exhaust
pipe to the center exhaust pipe.
(d) Re mo ve th e fo u r bo lts an d nu ts ho ld in g th e fro n t
exhaust pipe to the catalytic converter. Remove the pipe
support stay, front exhaust pipe and three gaskets.
29. REMOVE CATALYTIC CONVERTERS (MAIN) Remove the three nuts, catalytic converter and gasket. Re-
move the two catalytic converters.
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30. REMOVE TAILPIPES(a) Remove the four bolts holding the tailpipes to the centerexhaust pipe.
(b) Disconnect the tailpipe hook from the ring on tailpipe
bracket, and remove the tailpipe and gasket. Remove
the two tailpipes.
31. REMOVE CENTER EXHAUST PIPE Disconnect the two hooks of the exhaust pipe from the rings
on exhaust pipe brackets, and remove the center exhaust
pipe.
32. REMOVE EXHAUST PIPE HEAT INSULATOR Remove the four nuts and heat insulator.
33. REMOVE CENTER FLOOR BRACE Remove the four bolts and brace.
34. REMOVE PROPELLER SHAFT (See PR section)
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35. DISCONNECT TRANSMISSION CONTROL RODRemove the nut, and disconnect the control rod from the shift
lever.
36. REMOVE ENGINE AND TRANSMISSION A SSEMBLY
FROM VEHICLE
(a) Attach the engine hoist chain to the engine hangers.
(b) Remove the two nuts holding the engine mounting insulators to the front suspension crossmember.
(c) Remove the four bolts, four nuts and rear engine mounting member. Disconnect the ground strap.
(d) Lift the engine out of the vehicle slowly and carefully.
NOTICE: Be careful not to hit the PS gear housing, neu-
tral start switch and ABS actuator.
(e) Make sure the engine is clear of all wiring, hoses and cables.
(f) Place the engine and transmission assembly onto the stand.
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COMPONENTS FOR SEPARATION AND
ASSEMBLY OF ENGINE AND
TRANSMISSION
SEPARATION OF ENGINE AND
TRANSMISSION
1. REMOVE OIL DIPSTICK GUIDE FOR TRANSMISSION(a) Remove the mounting bolt.
(b) P u ll ou t th e dip stick gu id e an d dip stick fro m th etransmission.
(c) Remove the O±ring from the dipstick guide.
2. REMOVE OIL COOLER PIPES FOR TRANSMISSION (a) Remove the two mounting bolts.
(b) Loosen the two union nuts, and remove the oil coolerpipes.
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3. DISCONNECT ENGINE WIRE FROM TRANSMISSION(a) Disconnect the following connectors:(1) O/D direct clutch speed sensor connector
(2) No.1 speed sensor connector
(3) No.2 speed sensor connector
(4) Neutral start switch connector
(b) Disconnect the five wire clamps from the brackets on the
transmission.
4. SEPARATE ENGINE AND TRANSMISSION (See AT section)
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COMPONENTS FOR DISASSEMBLY AND ASSEMBLY OF CYLINDER BLOCK
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PREPARATION FOR DISASSEMBLY
(See Components on page EM±131)
1. REMOVE DRIVE PLATE Remove the eight bolts, two spacers and drive plate.
2. INSTALL ENGINE TO ENGINE STAND FOR DISASSEMBLY
3. REMOVE TIMING BELT AND PULLEYS (See pages EM±36 to 44)
4. REMOVE Cylinder Block (See pages EM±61 to 75)
5. REMOVE RH ENGINE MOUNTING BRACKET Remove the four bolts and mounting bracket.
6. REMOVE LH ENGINE MOUNTING BRACKET (a) Remove the clamp bolt, and disconnect the engine wirefrom the engine mounting bracket.
(b) Remove the four bolts and mounting bracket.
7. REMOVE STARTER (a) Remove the two bolts, and disconnect the starter fromthe cylinder block.
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(b) Disconnect the wire clamp from the bracket on thestarter.
(c) Remove the nut, and disconnect the wire.
(d) Disconnect the connector, and remove the starter.
8. REMOVE KNOCK SENSORS (a) Disconnect the two knock sensor connectors.
(b) Using SST, remove the two knock sensors.
SST 09816±30010
9. REMOVE WATER BY±PASS PIPE (a) Remove the two bolts.
(b) Pull out the by±pass pipe from the water pump.
(c) Remove the O±ring from the by±pass pipe.
10. REMOVE ENGINE WIRE (a) Disconnect the following connectors:(1) Oil level sensor connector
(2) Oil pressure switch connector
(b) Remove the three bolts and wire cover from the LH side
of the cylinder block.
(c) Remove the two bolts and engine wire.
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11. REMOVE WATER PUMP(a) Remove the five mounting bolt, two mounting stud boltsand mounting nut.
(b) Remove the water pump by prying the portions between
the water pump and cylinder block with a screwdriver.
12. REMOVE NO.2 AND NO.1 OIL PANS (See steps 7 to 12 on pages LU±9 to 11)
13. REMOVE OIL PUMP (a) Remove the eight mounting bolts.
(b) Remove the oil pump by prying the portions between the
oil pump and cylinder block with a screwdriver.
(c) Remove the O±ring from the cylinder block.
14. REMOVE ALTERNATOR BRACKET Remove the bolt and bracket.
15. REMOVE WATER SEAL PLATE
Remove the two nuts and seal plate.
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DISASSEMBLY OF CYLINDER BLOCK
(See Components on page EM±131)
1. REMOVE REAR OIL SEAL RETAINER (a) Remove the seven bolts.
(b) Remove the oil seal retainer by prying the portions
between the oil seal retainer and main bearing cap with
a screwdriver.
(c) Remove the O±ring.
2. CHECK CONNECTING ROD THRUST CLEARANCE Using a dial indicator, measure the thrust clearance while
moving the two connecting rods back and forth.
Standard thrust clearance: 0.160±0.290 mm
(0.0063±0.0114 in.)
Maximum thrust clearance: 0.35 mm (0.0138 in.)
If the thrust clearance is greater than maximum, replace the
connecting rod assembly(s). If necessary, replace the crank-
shaft.
Connecting rod thickness: 22.880±22.920 mm (0.9008±0.9024 in.)
3. REMOVE CONNECTING ROD CAPS AND CHECK OILCLEARANCE
(a) Using a punch or numbering stamp, place thematchmarks on the connecting rod and cap to ensure
correct reassembly.
(b) Using SST, remove the two connecting rod bolts.
SST 09011±38121
(c) Using the two removed connecting rod bolts, remove the connecting rod cap and lower bearing by wiggling
the connecting rod cap right and left.
HINT: Keep the lower bearing inserted with the connecting rod cap.
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