4.3L V8: Other — Lexus LS III (2000-2003)

FUEL PRESSURE RELEASE

Working from inside luggage compartment, disconnect fuel pump connector on top of fuel tank. Start engine. When engine stops running, turn ignition off, and disconnect negative battery cable. Place suitable container under fuel line. Cover fuel line connection with shop towel. Slowly loosen fuel line connection to release fuel pressure. Once fuel pressure is released, plug openings with rubber plugs. Reconnect fuel pump connector.

COOLING SYSTEM BLEEDING

Slowly pour coolant into radiator reservoir until full. Install radiator and radiator reservoir filler caps. Start engine. Turn on vehicle heater. Increase engine speed to 2000-2500 RPM and run until engine reaches normal operating temperature. Stop engine. NOTE: DO NOT use an alcohol type coolant or plain water alone. Mix coolant with demineralized or distilled water.
Wait until engine coolant cools down. Remove radiator and reservoir caps and fill system with coolant until full. Install radiator and reservoir filler caps.

ENGINE

Note. Remove engine and transmission as an assembly.

WARNING

To prevent air bag deployment, disconnect negative battery cable, and wait at least 90 seconds before working on vehicle.

CAMSHAFT

CAUTION

Release fuel pressure before disconnecting fuel line. See FUEL PRESSURE RELEASE .

Scheme 27

Scheme 27: Removal

Scheme 28

Disconnect negative battery cable. Drain cooling system. Remove engine "V" bank and side covers. Remove intake air duct and air cleaner assembly. Remove radiator and cooling fans assembly. Remove timing belt. See «TIMING BELT»(ref-131978-S15835946542002010500000). Remove camshaft position sensor.
Remove LH and RH timing belt rear plates. Remove valve covers. If necessary, remove camshaft semi-circular plugs. Remove camshaft timing oil control valve from front camshaft bearing cap.
To avoid valve/piston interference, ensure timing mark on crankshaft pulley is aligned with center of crankshaft pulley bolt and center of No. 2 timing belt idler pulley bolt. see scheme 7
Using Variable Pin Wrench Set (09960-10010), and a shop rag to absorb oil, turn camshaft from left to right 25 degrees, 2 to 3 times, to release oil from front bearing cap timing oil control valve installation hole. Approximately 1.2 cu. in. (20 cc) of oil will be ejected.
Using a wrench on cast camshaft hex, turn LH exhaust camshaft to bring service bolt hole of sub-gear up. Secure sub-gear on LH exhaust camshaft to main gear with a service bolt (6 x 1 x 20 mm). (Scheme 27) Rotate camshafts so dot marks on LH camshaft gears align with each other. see scheme 2
Using a wrench on cast camshaft hex, turn RH exhaust camshaft to bring service bolt hole of sub-gear up. Secure sub-gear on RH exhaust camshaft to main gear with a service bolt (6 x 1 x 20 mm). (Scheme 27) Rotate RH exhaust camshaft to position timing mark (one dot) at a 10-degree angle above timing mark mating level on intake gear.
Evenly loosen camshaft bearing cap bolts in sequence, using several steps. (Scheme 28) Remove 4 seal washers, oil feed pipe, 9 bearing caps, oil control valve filter, and 2 camshafts, from each cylinder head. Arrange bearing caps in order of removal.
To disassemble exhaust camshaft, mount cast hexagonal area of camshaft in soft-jaw vise. Using Variable Pin Wrench Set (09960-10010), rotate sub-gear clockwise and remove service bolt. Remove snap ring, wave washer, sub-gear and gear spring. To disassemble intake camshaft, mount cast hexagonal area of camshaft in soft-jaw vise. Remove center plug and seal washer. Using a 10-mm hex wrench, remove bolt from timing tube assembly. Remove timing tube and drive gear assembly. Using Variable Pin Wrench Set (09960-10010) and 5 mm hexagon (Allen) wrench, remove 4 Allen bolts, drive gear and oil seal from timing tube.

OIL PAN

Note. Manufacturer lists procedure with engine removed.

Cylinder Head

Inspect cylinder head for warpage at cylinder block mounting surface and both manifold mounting surfaces. Replace cylinder head if warpage exceeds specification. See «CYLINDER HEAD»(ref-131978-S01189885142002010500000) table under ENGINE SPECIFICATIONS.
To check camshaft oil clearance, using Plastigage, install camshaft in cylinder head using proper procedure. See «CAMSHAFT»(ref-131978-S29833318072002010500000) under REMOVAL & INSTALLATION.
Replace camshaft and/or cylinder head and bearing caps if oil clearance is not within specification. See «CAMSHAFT»(ref-131978-S34847070992002010500000) table under ENGINE SPECIFICATIONS.
Using a dial indicator, check camshaft end play (thrust clearance) with camshaft bearing cap bolts tightened to specification. Replace camshaft and/or cylinder head and bearing caps if end play is not within specification. See «CAMSHAFT»(ref-131978-S34847070992002010500000) table under ENGINE SPECIFICATIONS.
Ensure valve lifter oil clearance is within specification. See «VALVE LIFTERS»(ref-131978-S21248805762002010500000) table under ENGINE SPECIFICATIONS.
If replacing cylinder head, apply a coat of Three Bond (1234) .59" (15 mm) wide around sealing end of spark plug tube. Using a wooden block and hammer, tap spark plug tubes into cylinder head until distance from top of spark plug tube protrudes 1.906-1.953" (48.41-49.61 mm). above camshaft bearing cap installation surface of cylinder head.

Valve Springs

Ensure valve spring free length, tension pressure and out-of-square are within specification. See VALVES & VALVE SPRINGS table under ENGINE SPECIFICATIONS.

Valve Stem Oil Seals

Valve stem oil seals are color coded on one end for identification. Exhaust valve stem oil seals are Gray and intake valve stem oil seals are Brown. Lubricate valve stem oil seal with engine oil before installation. Use Valve Stem Oil Seal Installer (09201-41020) to install valve stem oil seal.

Valve Guides

Using a valve guide bushing brush and cleaning solvent, clean inside diameter of all valve guides. Ensure valve guide inside diameter is within specification. See «CYLINDER HEAD»(ref-131978-S01189885142002010500000) table under ENGINE SPECIFICATIONS. Replace valve guide if inside diameter exceeds specification.
To replace valve guide, submerge cylinder head in a suitable container filled with water, and heat to 176-212°F (80-100°C). When cylinder head has reached specified temperature, remove and place on bench. Using a hammer, Valve Guide Remover/Installer (09201-1000) and Handle (09951-07100), drive out valve guide from camshaft (upper) side of cylinder head.
Using a caliper gauge, measure inside diameter of cylinder head valve guide bushing bore. If inside diameter is .4049-.4057" (10.285-10.306 mm), use standard valve guide.
If inside diameter of bore exceeds .4057" (10.306 mm), machine valve guide bushing bore to .4069-.4077" (10.335-10.356 mm) for oversize valve guide. Replace cylinder head if inside diameter of bore exceeds .4077" (10.356 mm). CAUTION: Exhaust valve guide is 1.594" (40.5 mm) long and intake valve guide is 1.358" (34.5 mm) long. Ensure proper length valve guide is installed in the correct location.
To install valve guide, submerge cylinder head in a suitable container filled with water and heat to 176-212°F (80-100°C). When cylinder head has reached specified temperature, remove and place on bench. Using a hammer, Valve Guide Remover/Installer (09201-1000) and Handle (09951-07100), drive valve guide in from camshaft (upper) side of cylinder head, until valve guide protrudes .362-.386" (9.2-9.8 mm) for intake or .323-.346" (8.2-8.8 mm) for exhaust, above spring seat.
Using a sharp 5.5-mm reamer, ream valve guide to obtain standard valve stem-to-guide oil clearance. See «CYLINDER HEAD»(ref-131978-S01189885142002010500000) table under ENGINE SPECIFICATIONS.

Valves

Ensure minimum overall refinish length, stem diameter and valve head margin are within specification. See VALVES & VALVE SPRINGS table under ENGINE SPECIFICATIONS.

Valve Seat

Ensure valve seat angle and seat width are within specification. See CYLINDER HEAD table under ENGINE SPECIFICATIONS. Valve seat replacement information is not available from manufacturer.

Valve Seat Correction Angles

If valve seat is too high, use 30-degree and 45-degree stones to lower valve seat contact area. If valve seat is too low, use 60-degree and 45-degree stones to raise valve seat contact area.

Valve Lifters

Ensure valve lifter diameter, bore diameter and oil clearance are within specification. See VALVE LIFTERS table under ENGINE SPECIFICATIONS.

Scheme 29

Scheme 29: Piston & Rod Assembly

Ensure connecting rod and connecting rod cap are marked with matching cylinder number for reassembly reference before removal. Using a ridge reamer, remove ring ridge in cylinder bores before removing pistons (if necessary). Using a dial indicator, check connecting rod thrust (side) clearance before removal. If thrust clearance exceeds specification, replace connecting rod assembly and/or crankshaft. See «CONNECTING RODS»(ref-131978-S33392703492002010500000) table under ENGINE SPECIFICATIONS. NOTE: Top of right piston contains 2 cavities for front mark, and left piston contains one cavity for front mark. Pistons are also marked "R" for right side and "L" for left side on piston boss. Connecting rod caps have an outside mark that should face toward crankshaft on installation. (Scheme 30) Piston must be installed with front cavity marks properly positioned in relation to outside mark on connecting rod cap. Reference to right and left indicates sides as viewed from rear of engine (drive plate end).
Remove connecting rod cap. Using Plastigage, check rod bearing oil clearance, with rod cap bolts tightened to specification. Remove rod cap and Plastigage and measure thickness of Plastigage to determine oil clearance. If clearance is not within specification, replace rod bearings and/or crankshaft. Remove piston and connecting rod assembly from cylinder block. Keep connecting rod, bearings and rod cap together.
Using a ring expander, remove the 2 top compression rings, remove oil rings by hand. Using a small screwdriver, remove the 2 piston pin retaining rings from piston. Submerge piston and rod assembly in water and gradually heat to 140°F (60°C). Using a plastic mallet and brass bar, lightly tap piston pin out and remove connecting rod from piston.
Ensure piston pin diameter is within specification. See «PISTONS, PINS & RINGS»(ref-131978-S05965238932002010500000) table under ENGINE SPECIFICATIONS.
Ensure connecting rod piston pin bushing bore diameter, crankpin bore diameter, and rod bend and twist are within specification. See «CONNECTING RODS»(ref-131978-S33392703492002010500000) table under ENGINE SPECIFICATIONS.
Using a press and appropriate driver, bushing in connecting rod can be replaced if bore diameter is not within specification. Ensure bushing oil hole aligns with connecting rod oil hole during installation. Hone bushing to obtain correct piston pin-to-rod clearance.
To reassemble, install NEW piston pin retaining ring in piston. Install piston on connecting rod so front mark on piston is properly positioned with outside mark on connecting rod cap. (Scheme 30) Heat piston to 140°F (60°C) in water. Coat piston pin with engine oil. Install piston pin through piston and connecting rod bushing. Install remaining NEW piston pin retaining ring in piston.

Scheme 30

Scheme 30: Fitting Pistons

Scheme 31

Different piston and cylinder bore sizes are used. Piston diameter is determined by size mark ("1", "2" or "3") stamped on top of piston. Cylinder bore diameter is determined by size mark ("1", "2" or "3") stamped on cylinder block deck surface near each respective cylinder. (Scheme 31)
To determine piston-to-cylinder clearance, measure piston diameter and cylinder bore diameter. Measure piston skirt diameter 1.04" (26. mm) from top of piston, at 90-degree angle to piston pin. Ensure piston diameter is within specification. See «PISTONS, PINS & RINGS»(ref-131978-S05965238932002010500000) table under ENGINE SPECIFICATIONS.
Using cylinder gauge, measure cylinder bore at positions "A", "B", and "C" in axial thrust directions. (Scheme 32) Ensure cylinder bore diameter, taper and out-of-round measurements are within specification. See «CYLINDER BLOCK»(ref-131978-S07239423202002010500000) table under ENGINE SPECIFICATIONS. Replace cylinder block if cylinder bore diameter exceeds specification.
Determine piston clearance. If clearance is not within specification, replace piston or cylinder block. See «PISTONS, PINS & RINGS»(ref-131978-S05965238932002010500000) table under ENGINE SPECIFICATIONS.

Piston Rings

Ensure piston ring end gap and side clearance in ring groove are within specification. See PISTONS, PINS & RINGS table under ENGINE SPECIFICATIONS. Install piston rings with identification mark on ring facing toward top of piston. Stagger ring gaps on piston before installation. (Scheme 33)

Note. Top ring is marked 1R and second ring is marked with 2R identification marks.

Scheme 32

Scheme 32: Piston Rings

Scheme 33

Scheme 33: Rod Bearings

Ensure connecting rod cap is marked with proper cylinder number before disassembly. Connecting rod and piston assembly must be installed with front mark on piston facing toward front of engine (timing belt end) and outside mark on rod cap facing toward crankshaft.
Connecting rod cap, rod bearing and crankshaft are stamped with size marks. There are 6 sizes of standard bearings marked 2, 3, 4, 5, 6 and 7. If replacing rod bearing, ensure size mark on NEW rod bearing is the same as size mark on original rod bearing. (Scheme 34) If size mark on original rod bearing cannot be determined, add size mark on crankshaft and size mark on connecting rod cap together, to determine size of NEW rod bearing to be used. For example, if size mark on crankshaft is "1" and size mark on connecting rod cap is "3", use rod bearing with size mark "4".
Rod bearing thickness is also determined by size mark. See «ROD BEARING SPECIFICATIONS»(ref-131978-S09535691192002010500000) table. ROD BEARING SPECIFICATIONS Size Mark Bearing Thickness - In. (mm) "2".0584-.0585 (1.484-1.487) "3".0585-.0587 (1.487-1.490) "4".0587-.0588 (1.490-1.493) "5".0588-.0589 (1.493-1.496) "6".0589-.0590 (1.496-1.499) "7".0590-.0591 (1.499-1.502)
Ensure connecting rod and piston assembly is installed with front mark on piston pointing toward front of engine (timing belt end) and outside mark on rod cap facing toward crankshaft. On right pistons, outside mark on connecting rod cap must face rear end of engine. On left pistons, outside mark on connecting rod cap must face front of engine. Using a ring compressor, install piston and rod assembly into cylinder block.
Coat threads of connecting rod bolt and under bolt heads with engine oil before installation. Install rod cap bolts and alternately tighten to specification, in 2 steps. See «TORQUE SPECIFICATIONS»(ref-131978-S04317680092002010500000).
Use plastigage to check rod bearing clearance. Ensure rod bearing oil clearance and connecting rod side clearance are within specification. See «CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS»(ref-131978-S25532325812002010500000) and «CONNECTING RODS»(ref-131978-S33392703492002010500000) tables under ENGINE SPECIFICATIONS.

Scheme 34

Scheme 34: Crankshaft & Main Bearings

Scheme 35

Scheme 36

Scheme 37

Remove 7 bolts and remove rear oil seal retainer and "O" ring. Using a dial indicator, check crankshaft end play before removing crankshaft from cylinder block. Replace thrust bearings if end play is not within specification. See «CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS»(ref-131978-S25532325812002010500000) table under ENGINE SPECIFICATIONS. Thrust bearings are on No. 3 journal.
Main bearing caps are numbered 1-5 for location, with No. 1 at timing belt (front) end and No. 5 at drive plate (rear) end. Note that arrows on main bearing caps point toward timing belt end of engine. Remove 10 side main bearing cap bolts located on sides of cylinder block.
Evenly loosen the 20 main bearing cap bolts in sequence, using several steps. (Scheme 35) Remove main bearing cap bolts and main bearing caps. Lift crankshaft from cylinder block. Remove thrust bearings from journal No. 3.
Reinstall main bearing caps with bearings to cylinder block, without crankshaft, and tighten bolts to specification. Using cylinder bore gauge, measure inside diameter of main bearings. Main bearing inside diameter should be 2.6372-2.6378" (66.985-67.000 mm). Using an outside micrometer, measure outside diameter of crankshaft main bearing journals. Subtract main bearing journal diameter from main bearing inside diameter to determine oil clearance. If clearance exceeds specification, replace bearings and/or crankshaft.
If replacing bearing, ensure size mark on NEW bearing is the same as size mark on original bearing. Main bearing size mark ("1", "2", "3", "4" or "5") is located on back of main bearing. (Scheme 36) If size mark on original bearing cannot be determined, add size mark on crankshaft to size mark on cylinder block, and refer to charts in figure to determine size of NEW bearing to be used. (Scheme 37)
Cylinder block main bearing bore inside diameter is identified by main bearing bore size mark stamped on cylinder block. (Scheme 36) Crankshaft main bearing journal diameter is determined by size mark located on crankshaft counterweight.
Main bearing thickness is also determined by size mark. See «MAIN BEARING SPECIFICATIONS»(ref-131978-S07333686372002010500000) table. MAIN BEARING SPECIFICATIONS Size Mark Bearing Thickness - In. (mm) No. 1 & No. 5 Bearings "3".0981-.0982 (2.492-2.494) "4".0982-.0983 (2.494-2.497) "5".0983-.0985 (2.497-2.502) "6".0985-.0986 (2.502-2.504) "7".0986-.0987 (2.504-2.507) No. 2, 3 & 4 Bearings "1".0979-.0980 (2.487-2.489) "2".0980-.0981 (2.489-2.492) "3".0981-.0982 (2.492-2.494) "4".0982-.0983 (2.494-2.497) "5".0983-.0985 (2.497-2.502)
Ensure journal diameter, taper and out-of-round are within specification. Replace crankshaft if not within specification. See «CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS»(ref-131978-S25532325812002010500000) table under ENGINE SPECIFICATIONS.
Main bearings come in widths of.768" (19.5 mm) and.886" (22.5 mm). (Scheme 38) Install the 2 wide main bearings in No. 1 (timing belt end) and No. 5 (drive plate end) positions. Install the remaining narrow main bearings in all other locations. Ensure upper main bearings installed in cylinder block contain oil holes and oil grooves. Lower main bearings installed in main bearing caps, do not have oil holes or grooves.
Use Plastigage to check main bearing oil clearance. Coat threads and under head of main bearing bolts with engine oil. Install main bearing caps and tighten bolts to specification. Remove main bearing caps and measure thickness of Plastigage to determine clearance. If clearance is not within specification, replace bearings with appropriate size to obtain correct clearance.
Install thrust washers on No. 3 main bearing in cylinder block and main bearing cap, with grooved sides facing outward, toward crankshaft. Install crankshaft and main bearing caps. Main bearing caps must be installed with arrow on top of cap pointing toward timing belt end of engine. Ensure main bearing caps are installed in numerical order, with No. 1 at timing belt end of engine and No. 5 at drive plate end.
Install and tighten main bearing cap bolts to specification in sequence, using 2 steps. See «TORQUE SPECIFICATIONS»(ref-131978-S04317680092002010500000).
Ensure crankshaft end play is within specification. See «CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS»(ref-131978-S25532325812002010500000) table under ENGINE SPECIFICATIONS. Replace thrust bearing if end play is not within specification.
Install NEW seal washers on the 10 main bearing cap side bolts located on sides of cylinder block. Install bolts and tighten to specification. See «TORQUE SPECIFICATIONS»(ref-131978-S04317680092002010500000).

Thrust Bearing

Install thrust bearing on No. 3 main bearing journal with grooves facing outward, toward crankshaft. Thrust bearing must be replaced if crankshaft end play is not within specification. See CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS table under ENGINE SPECIFICATIONS.

Cylinder Block

Inspect cylinder block deck surface warpage. Replace cylinder block if deck warpage exceeds specification. See «CYLINDER BLOCK»(ref-131978-S07239423202002010500000) table under ENGINE SPECIFICATIONS.
Measure cylinder bore diameter at.39" (9.9 mm) from top and bottom of cylinder bore and at middle of cylinder bore. Different cylinder bore sizes are used. Cylinder bore diameter is determined by size mark ("1", "2" or "3") stamped on cylinder block deck surface. (Scheme 31)
Ensure cylinder bore diameter is within specification. See «CYLINDER BLOCK»(ref-131978-S07239423202002010500000) table under ENGINE SPECIFICATIONS. Replace cylinder block if cylinder bore diameter exceeds specification.

Note. Main bearing bore inside diameter is determined by main bearing bore size mark stamped on cylinder block. (Scheme 34)

Oil Pressure

With engine at normal operating temperature, oil pressure should be at least 4.2 psi (0.3 kg/cm 2 ) at idle, and 43-85 psi (3.0-6.0 kg/cm 2 ) at 3000 RPM.

OIL PUMP