LEXUS SC400 1991 Service Repair Manual

11. REMOVE WATER PUMP
(a) Remove the 5 bolts, 2 stud bolts and nut.
(b) Using a screwdriver remove the water pump by prying theportions between the water pump and cylinder block.
12. REMOVE NO.2 AND NO.1 OIL PANS
(See steps 9 to 14 on pages EG±501 and 502)
13. REMOVE OIL PUMP
(a) Remove the 8 bolts.
(b) Using a screwdriver, remove the oil pump by prying the portions between the oil pump and cylinder block.
(c) Remove the O±ring from the cylinder block.
14. REMOVE GENERATOR BRACKET
Remove the bolt and generator bracket.
15. REMOVE WATER SEAL PLATE
Remove the 2 bolts and seal plate.
±
1UZ±FE ENGINE ENGINE MECHANICALEG±155
WhereEverybodyKnowsYourName

CYLINDER BLOCK DISASSEMBLY
EG1KT±04
(See Components for Cylinder Block Disassembly and As-sembly)
1. REMOVE REAR OIL SEAL RETAINER
(a) Remove the 7 bolts.
(b) Using a screwdriver, remove the oil sel retainer by prying the portions between the oil seal retainer and main bearing cap.
(c) Remove the O±ring.
2. CHECK CONNECTING ROD OIL CLEARANCE Using a dial indicator, measure the thrust clearance while
moving the connecting rod back an forth.
Standard thrust clearance:
0.160 ± 0.290 mm (0.0063 ± 0.0138 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) Check the matchmarks on the connecting rod and cap to ensure correct reassembly.
(b) Remove the 2 connecting rod cap bolts.
(c) Using the 2 removed connecting rod cap 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.
EG±156
±
1UZ±FE ENGINE ENGINE MECHANICAL
WhereEverybodyKnowsYourName

(d) Clean the crank pin and bearing.
(e) Check the crank pin and bearing for pitting and scratches.If the crank pin or bearing is damaged, replace the bearings.
If necessary, replace the crankshaft.
(f) Lay a strip of Plastigage across the crank pin.
(g) Install the connecting rod cap with the 2 bolts. (See step 7 on page EG±183)
Torque:
1st 25 N Vm (250 kgf Vcm, 18 ft Vlbf)
2nd Turn 90 5
NOTICE: Do not turn the crankshaft.
(h) Remove the 2 bolts, connecting rod cap and lower bearing. (See procedure (b) and (c) above)
(i) Measure the Plastigage at its widest point.
Standard oil clearance: 0.027 ± 0.053 mm (0.0011 ± 0.0021 in.)
Maximum oil clearance: 0.065 mm (0.0026 in.)
If the oil clearance is greater than maximum, replace the
bearings. If necessary, replace the crankshaft.
±
1UZ±FE ENGINE ENGINE MECHANICALEG±157
WhereEverybodyKnowsYourName

HINT: If using a standard bearing, replace it with one having
the same number. If the number of the bearing cannot be de-
termined, select the correct bearing by adding together the
numbers imprinted on the connecting rod cap and crank-
shaft, then selecting the bearing with the same number as the
total. There are 6 sizes of standard bearings, marked ª2º, ª3º,
ª4º, ª5º, ª6º and ª7º accordingly.
EXAMPLE: Connecting rod cap ª3º + Crankshaft ª1º = Total
number 4 (Use bearing ª4º)
V01595
Reference:
Connecting rod big end inside diameter:
Mark ª1º55.000 ± 55.006 mm (2.1654 ± 2.1656 in.)
Mark ª2º
55.006 ± 55.012 mm (2.1656 ± 2.1658 in.)
Mark ª3º 55.012 ± 55.018 mm (2.1658 ± 2.1661 in.)
Mark ª4º
55.018 ± 55.024 mm (2.1661 ± 2.1663 in.)
Crankshaft crank pin diameter: Mark ª1º51.994 ± 52.000 mm (2.0470 ± 2.0472 in.)
Mark ª2º
51.988 ± 51.994 mm (2.0468 ± 2.0470 in.)
Mark ª3º 51.982 ± 51.988 mm (2.0465 ± 2.0468 in.)
Standard sized bearing center wall thickness:
Mark ª2º1.484 ± 1.487 mm (0.0584 ± 0.0585 in.)
Mark ª3º 1.487 ± 1.490 mm (0.0585 ± 0.0587 in.)
Mark ª4º
1.490 ± 1.493 mm (0.0587 ± 0.0588 in.)
Mark ª5º 1.493 ± 1.496 mm (0.0588 ± 0.0589 in.)
Mark ª6º
1.496 ± 1.499 mm (0.0589 ± 0.0590 in.)
Mark ª7º 1.499 ± 1.502 mm (0.0590 ± 0.0591 in.)
(j) Completely remove the Plastigage.
EG±158
±
1UZ±FE ENGINE ENGINE MECHANICAL
WhereEverybodyKnowsYourName

4. REMOVE PISTON AND CONNECTING RODASSEMBLIES
(a) Using a ridge reamer, remove all the carbon from the top of
the cylinder.
(b) Push the piston, connecting rod assembly and upper bearing through the top of the cylinder block.
HINT:
wKeep the bearings, connecting rod and cap together.
w Arrange the piston and connecting rod assemblies in
correct order.
5. CHECK CRANKSHAFT THRUST CLEARANCE Using a dial indi cator, measure the thrust clearance while pry-
ing the crankshaft back and forth with a screwdriver.
Standard thrust clearance:
0.020 ± 0.220 mm (0.0008 ± 0.0087 in.)
Maximum thrust clearance: 0.30 mm (0.0118 in.)
If the thrust clearance is greater than maximum, replace the
thrust washers as a set.
Thrust washer thickness:2.440 ± 2.490 mm (0.0961 ± 0.0980 in.)
±
1UZ±FE ENGINE ENGINE MECHANICALEG±159
WhereEverybodyKnowsYourName

6. REMOVE MAIN BEARING CAPS AND CHECK OILCLEARANCE
(a) Remove the 10 main bearing cap bolts.
(b) Uniformly loosen and remove the 20 main bearing cap nuts
in several passes, in the sequence shown.
(c) Using 2 screwdrivers, pry out the main bearing cap, and remove the 5 main bearing caps, lower bearings and lower
thrust washers (No.3 main bearing cap only).
NOTICE: Be careful not to damage the cylinder block.
HINT:
wKeep the lower bearing and main bearing cap together.
w Arrange the main bearing caps and lower thrust
washers in correct order.
(d) Lift out the crankshaft.
(e) Remove the 2 upper thrust washers. HINT:
wArrange the upper thrust washers in correct order.
w Keep the upper bearings together with the cylinder
block.
(f) Clean each main journal and bearing.
(g) Ch e ck ea ch ma in jo u rn a l an d be a rin g fo r pittin g an d scratches.
If the journal or bearing is damaged, replace the bearings. If
necessary, replace the crankshaft.
EG±160
±
1UZ±FE ENGINE ENGINE MECHANICAL
WhereEverybodyKnowsYourName

(h) Install the 5 main bearing caps with the 20 nuts and ten bolts.
Do not install the crankshaft.
(See step 4 on page EG±180)
Torque:
Nut1st 27 N Vm (275 kgf Vcm, 20 ft Vlbf)
2nd Turn 90 5
Bolt 49 N Vm (500 kgf Vcm, 36 ft Vlbf)
(i) Using a cylinder gauge, measure the inside diameter of the
the main bearing.
Bearing inside diameter:
67.026 ± 67.033 mm (2.6388 ± 2.6391 in.)
(j) Using a, micrometer measure the diameter of the mainjournal
Main journal diameter:
66.988 ± 67.000 mm (2.6373 ± 2.6378 in.)
(k) Subtract the main journal diameter measurement from themain bearing inside diameter measurement.
Standard clearance:
0.026 ± 0.045 mm (0.0010 ± 0.0018 in.)
Maximum clearance: 0.055 mm (0.0022 in.)
If the oil clearance is greater than maximum, replace the
bearings. If necessary, replace the crankshaft.
±
1UZ±FE ENGINE ENGINE MECHANICALEG±161
WhereEverybodyKnowsYourName

HINT: If using a standard bearing, replace it with one having
the same number. If the number of the bearing cannot be de-
termined, select the correct bearing by adding together the
numbers imprinted on the cylinder block and crankshaft, then
refer to the table below for the appropriate bearing number.
There are 5 sizes of the standard bearings, marked ª1º, ª2º,\
ª3º, ª4º and ª5º accordingly.
EXAMPLE: Cylinder block ª06º (A) + Crankshaft ª08º (B)
= Total number 14 (Use bearing ª3º)
V01565
Reference:
Cylinder block main journal bore diameter (A):
Mark ª00º72.000 mm (2.8346 in.)
Mark ª01º 72.001 mm (2.8347 in.)
Mark ª02º 72.002 mm (2.8347 in.)
Mark ª03º 72.003 mm (2.8348 in.)
Mark ª04º 72.004 mm (2.8348 in.)
Mark ª05º 72.005 mm (2.8348 in.)
Mark ª06º
72.006 mm (2.8349 in.)
Mark ª07º 72.007 mm (2.8349 in.)
Mark ª08º
72.008 mm (2.8350 in.)
Mark ª09º 72.009 mm (2.8350 in.)
Mark ª10º 72.010 mm (2.8350 in.)
Mark ª11º 72.011 mm (2.8351 in.)
Mark ª12º 72.012 mm (2.8351 in.)
Mark ª13º 72.013 mm (2.8352 in.)
EG±162±
1UZ±FE ENGINE ENGINE MECHANICAL
WhereEverybodyKnowsYourName

Mark ª14º72.014 mm (2.8352 in.)
Mark ª15º
72.015 mm (2.8352 in.)
Mark ª16º 72.016 mm (2.8353 in.)
Crankshaft main journal diameter (B): Mark ª00º
67.000 mm (2.8378 in.)
Mark ª01º 66.999 mm (2.6378 in.)
Mark ª02º
66.998 mm (2.6377 in.)
Mark ª03º 66.997 mm (2.5377 in.)
Mark ª04º 66.996 mm (2.6376 in.)
Mark ª05º 66.995 mm (2.6376 in.)
Mark ª06º 66.994 mm (2.6376 in.)
Mark ª07º 66.993 mm (2.6375 in.)
Mark ª08º 66.992 mm (2.6375 in.)
Mark ª09º
66.991 mm (2.6374 in.)
Mark ª10º 66.990 mm (2.6374 in.)
Mark ª11º
66.989 mm (2.6374 in.)
Mark ª12º 66.988 mm (2.6373 in.)
Standard sized bearing center wall thickness: Mark ª1º
2.486 ± 2.489 mm (0.0979 ± 0.0980 in.)
Mark ª2º 2.489 ± 2.492 mm (0.0980 ± 0.0981 in.)
Mark ª3º
2.492 ± 2.495 mm (0.0981 ± 0.0982 in.)
Mark ª4º 2.495 ± 2.498 mm (0.0982 ± 0.0983 in.)
Mark ª5º 2.498 ± 2.501 mm (0.0983 ± 0.0985 in.)
±
1UZ±FE ENGINE ENGINE MECHANICALEG±163
WhereEverybodyKnowsYourName

Standard sized Bearing Selection Chart
 


Crankshaft
number mark\
 
\

\

Cylinder block number mark
  00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16
 00 1 1 1 1 1 1 2 2 2 2 2 2 3 3 3 3 3
 01 1 1 1 1 1 2 2 2 2 2 2 3 3 3 3 3 3
 02 1 1 1 1 2 2 2 2 2 2 3 3 3 3 3 3 4
 03 1 1 1 2 2 2 2 2 2 3 3 3 3 3 3 4 4 04 1 1 2 2 2 2 2 2 3 3 3 3 3 3 4 4 4 

05
 

1
 

2
 

2
 

2
 

2
 

2
 

2
 

3
 


3


3
 

3
 

3
 

3
 

4
 

4
 

4
 

4
 06 2 2 2 2 2 2 3 3 3 3 3 3 4 4 4 4 4
 07 2 2 2 2 2 3 3 3 3 3 3 4 4 4 4 4 4
 08 2 2 2 2 3 3 3 3 3 3 4 4 4 4 4 4 5
 09 2 2 2 3 3 3 3 3 3 4 4 4 4 4 4 5 5
 10 2 2 3 3 3 3 3 3 4 4 4 4 4 4 5 5 5 11 2 3 3 3 3 3 3 4 4 4 4 4 4 5 5 5 5 

12
 

3
 

3
 

3
 

3
 

3
 

3
 

4
 

4
 


4


4
 

4
 

4
 

5
 

5
 

5
 

5
 

5
EXAMPLE: Cylinder block ª06º, Crankshaft ª08º
= Use bearing ª3º
V01566
(l) Remove the 10 bolts, 20 nuts and 5 main bearing caps. (Seeprocedure (a) to (c) above)
(m) Remove the 5 upper main bearings from the cylinder block.
HINT: Arrange the main bearing caps, bearings and thrust
washers in correct order.
EG±164
±
1UZ±FE ENGINE ENGINE MECHANICAL
WhereEverybodyKnowsYourName