engine LEXUS SC400 1991 Service Repair Manual

DESCRIPTION
The 1 UZ±FE engine is an V±8 4.0 liter DOHC 32 valve engine.
OPERATION
EM±2±
ENGINE MECHANICAL Description, Operation
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DESCRIPTION
The 1 UZ±FE engine is an V±8 4.0 liter DOHC 32 valve engine.
OPERATION
EM±2±
ENGINE MECHANICAL Description, Operation
WhereEverybodyKnowsYourName

±
ENGINE MECHANICAL OperationEM±3
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The 1 UZ±FE engine has 8±cylinders in a V±arrangement at a bank an\
gle of 905. From the front of the RH
bank cylinders are numbered 2±4±6±8, and from the front of the LH b\
ank cylinders are numbered 1 ±3±5±7.
The crankshaft is supported by 5 bearings specified by the inside of the cr\
ankcase. These bearings are made
of a copper and lead alloy. The crankshaft is integrated with 8 weights which are cast along with it\
for balancing. Oil holes are built
into the center of the crankshaft for supplying oil to the connecting ro\
ds, pistons and other components. The ignition order is 1±8±4±3±6±5±7±2. The cylinder\
head is made of aluminum alloy, with a cross flow
type intake and exhaust layout and with pent±roof type combustion chambers. The spark plugs are loca\
ted in
the center of the combustion chambers.
At the front and rear of the intake manifold, a water passage has been p\
rovided which connects the RH
and LH cylinder heads. Exhaust and intake valves are equipped with irregular pitch springs made\
of special valve spring carbon
steel which are capable of following no matter what the engine speed.
The RH and LH intake camshafts are driven by a single timing belt, and a ge\
ar on the intake camshaft en-
gages with a gear on the exhaust camshaft to drive it. The camshaft jour\
nal is supported at 5 (intake) or 4 (ex-
haust) places between the valve lifters of each cylinder and on the front end of the cylinder \
head. Lubrication
of the cam journal gear is accomplished by oil being supplied through the \
oiler port in the center of the camshaft. Adjustment of the valve clearance is done by means of an outer shim type\
system, in which valve adjusting
shims are located above the valve lifters. This permits replacement of the sh\
ims without removal of the cam-
shafts. Pistons are made of high temperature±resistant aluminum alloy, and a depression is built into the piston
head to prevent interference with valves.
Piston pins are the full±floating type, with the pins fastened to neither the piston boss nor the connecting
rods. Instead, snap rings are fitted on both ends of the pins, preventing the\
pins from falling out. The No.1 compression ring is made of steel and the No.2 compression ring\
is made of cast iron. The oil
ring is m ade of a combination of steel and stainless steel. The outer diameter of\
each piston ring is slightly larger
than the diameter of the piston and the flexibility of the rings allows them\
to hug the cylinder walls when they
are mounted on the piston. Compression rings No.1 and No.2 work to prevent \
the leakage of gas from the cylin-
der and the oil ring works to scrape oil off the cylinder walls to prevent it from entering the combustion chamber. The cylinder block is made of aluminum alloy with a bank angle of 90 5. Cast iron cylinders are installed
inside the cylinder block. It has 8 cylinders which are approximately twice the length of th\
e piston stroke. The
top of each cylinder is closed off by the cylinder heads and the lower end of the cylinders becomes the crank-
case, in which the crankshaft is installed. In addition, the cylinder bl\
ock contains a water jacket, through which
coolant is pumped to cool the cylinders. The No.1 and No.2 oil pans are bolted onto the bottom of the cylinder block\
. The No.1 oil pan is made of
aluminum alloy. The No.2 oil pan is an oil reservoir made of pressed steel sheet. An o\
il level sensor is installed
in the No.1 oil pan (If the oil level drops below a set level, a warnin\
g light lights up.). A oil pan baffle plate keeps
sufficient oil in the bottom of the No.2 oil pan even when the vehicle is tilted. \
This dividing plate also prevents
the oil from making waves when the vehicle is stopped suddenly and the oil \
shifts away from the oil pump suction
pipe. Plastic region tightening bolts are used for the cylinder head, main bearing ca\
p and connecting rod.
EM±4
±
ENGINE MECHANICAL Operation
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PREPARATION
SST (SPECIAL SERVICE TOOLS)
09201±70010Valve Guide Bushing
Remover & Replacer
09202±70010Valve Spring
Compressor
09213±31021Crankshaft Pulley
Puller
09213±54015Crankshaft Pulley
Holding Toll
(91651±60855)(Bolt)
(09213±00020)(Body with Bolt)
(09213±00030)(Handle)
(09213±00040)(Attachment Set)
(09213±00050)(Bolt Set)
09213±60017Crankshaft Pulley &
Gear Puller Set
(09248±05011)(Valve Lifter Press)
09222±30010Connecting Rod
Bushing Remover
& Replacer
09223±15030Oil Seal and
Bearing Replacer
09248±55020Valve Clearance
Adjust Tool Set
Crankshaft rear oil seal
EM±4±
ENGINE MECHANICAL Preparation
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SST (SPECIAL SERVICE TOOLS) (Cont'd)
(09248±05021)(Valve Lifter
Stopper)
09316±60010Transmission &
Transfer Bearing
Replacer
Crankshaft timing pulley
09278±54012Drive Shaft Holding
Tool
M/T (W58) only
09325±20010Transmission Oil
Plug
(09316±00010)(Replacer Pipe)
Crankshaft front oil seal and camshaft oil seal
(09316±00050)(Replacer ºDº)
Camshaft oil seal
A/T (A340E) only
09325±40010Transmission Oil
Plug
Crankshaft pulley
09330±00021Companion Flange
Holding Tool
09608±30022Front Hub Bearing
Replacer Set
Knock sensor and oil pressure switch
09816±30010Oil Pressure
Switch Socket
(09608±05010)(Handle)
Crankshaft rear oiil seal
RECOMMENDED TOOLS
Cylinder head bolt
09043±5010010 mm Bi±Hexagon
wrench
A/C compressor mounting through bolt
09044±00020Torx Socket
E10
±
ENGINE MECHANICAL PreparationEM±5
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RECOMMENDED TOOLS (Cont'd)
For suspending engine
09090±04010Engine Sling
Device
Plug for the vacuum hose. fuel hose etc.
09258±00030Hose Plug Set
09200±00010Engine Adjust
Kit
EQUIPMENT
 Part Name\
 \
Note
 Caliper gauge\
 \

 CO/HC analyzer\
 \

 

Compression gauge
\
 
\

\
Cylinder compression pressure
 Connecting rod aligner\
 \

 Cylinder gauge\
 \

 Dial indicator\
 \

 

Engine tune±up tester
\
 
\

\

 Feeler gauge\
 \

 Micrometer\
 \

 

Straight edge\
 
\

\

 Spring tester\
 \
Valve spring
 Steel square\
 \
Valve spring
 Torque wrench\
 \

 

Vernier caliper
\
 
\

\

SSM (SPECIAL SERVICE MATERIALS)
 

Part Name 

Part No.\
 

\
Use etc.
 

Seal packing or equivalent 

08826±00080\
 

\

Camshaft bearing cap, Cylinder head cover,
Rear oil seal retainer and Oil pump
 




Adhesive 1324,
THREE BOND 1324 or equivalent
 




08833±00070
\
 



\

Drive plate mounting bolt
 




Adhesive 1344,
THREE BOND 1344,
LOCTITE 242 or equivalent 




08833±00080
\
 



\

Idler pulley mounting bolt
EM±6±
ENGINE MECHANICAL Preparation
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PREPARATION
SST (SPECIAL SERVICE TOOLS)
±
ENGINE MECHANICAL PreparationEM±5
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SST (SPECIAL SERVICE TOOLS) (Cont'd)
RECOMMENDED TOOLS
EM±6±
ENGINE MECHANICAL Preparation
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EQUIPMENT
 


Part Name\
 
\

\
Note
 Caliper gauge\
 \

 


HC/CO meter
\
 
\

\

 


Compression gauge\
 
\

\
Cylinder compression pressure
 Connecting rod aligner\
 \

 


Cylinder gauge
\
 
\

\

 


Dial indicator
\
 
\

\

 


Engine turn±up tester\
 
\

\

 Feeler gauge\
 \

 


Micrometer
\
 
\

\

 


Precision straight edge\
 
\

\

 Spring tester\
 \
Valve spring
 


Steel square
\
 
\

\
Valve spring
 


Torque wrench\
 
\

\

 Vernier caliper\
 \

SSM (SPECIAL SERVICE MATERIALS)
 
Part Name
 
Part No.
\
 \

Use etc.  \
 \

Camshaft bearing cap  \
 \
Camshaft bearing ca
Cylinder head semi±circular plug 
Seal packing or equivalent
 
08826±00080
\
 \
Cylinder head semi±circular lug
Cylinder head cover Seal acking or equivalent 08826±00080\
 \
Cylinder head cover
Rear oil seal retainer  \
 \
Rear oil seal retainer
Oil pump  \
 \

Water inlet housing Seal packing 1282B,
Th b d 1282B i l t
 08826±00100\
 \
Water inlet housing
Water seal plate Three bond 1282B or equivalent 08826±00100\
 \
Water seal late
Water pump 

Adhesive 1324,
Three bond 1324 or equivalent
 

08833±00070
\
 

\
Drive plate mounting bolt
 
Adhesive 1344,
 \
 \

 Adhesive 1344,
Three bond 1344
,
 
08833±00080
\
 \

No.1 idler pulley mounting bolt Three bond 1344,
Loctite 242 or equivalent 08833±00080\
 \
No.1 idler ulley mounting bolt
±
ENGINE MECHANICAL PreparationEM±7
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