Contents Wiring diagrams Section: Mechanical All sections

Engine Mechanical: Other Lexus IS I

Mechanical 5 illustrations ~1801 words

FUEL PRESSURE RELEASE

Open trunk. Remove luggage compartment floor mat and trim cover. Disconnect fuel pump electrical connector. Start engine and operate until it stalls. Reconnect fuel pump electrical connector. Fuel pressure is now released and fuel system components may be serviced.

CAMSHAFT

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

OIL PAN

Note. Manufacturer lists oil pan removal procedure with engine removed. See ENGINE .

Cylinder Head

  1. Inspect cylinder head warpage at cylinder block and manifold mating surfaces. Replace cylinder head if warpage exceeds specification. See «CYLINDER HEAD»(ref-159232-S11734303692003111900000) table under ENGINE SPECIFICATIONS.
  2. To check camshaft oil clearance, install camshaft in cylinder head without lifters installed. Install camshaft bearing caps. Lubricate and install camshaft bearing cap bolts. Alternately tighten bearing cap bolts until snug.
  3. Install Plastigage on camshaft journal. Install remaining camshaft bearing caps. DO NOT rotate camshaft. Tighten camshaft bearing cap bolts to specification in sequence using several steps. see scheme 29 See «TORQUE SPECIFICATIONS»(ref-159232-S31757476362003111900000).
  4. Remove bolts and No. 1 camshaft bearing cap from each camshaft. Remove remaining camshaft bearing cap bolts in sequence using several steps. see scheme 29
  5. Measure width of Plastigage to check oil clearance. Replace camshaft and/or cylinder head if oil clearance is not within specification. See «CAMSHAFT»(ref-159232-S34421256862003111900000) table under ENGINE SPECIFICATIONS.
  6. Check camshaft end play with camshaft bearing cap bolts tightened to specification. Replace camshaft and/or cylinder head if end play is not within specification. See «CAMSHAFT»(ref-159232-S34421256862003111900000) table under ENGINE SPECIFICATIONS.
  7. Ensure valve lifter bore diameter is within specification. See «VALVE LIFTERS»(ref-159232-S34330870112003111900000) table under ENGINE SPECIFICATIONS.
  8. When using replacement cylinder head, install original heater hose union (pipe that heater hose fits on) into cylinder head. Apply sealant on heater hose union. Install and tap heater hose union into cylinder head until distance from cylinder head surface to top of heater hose union is 1.89 in. (48.0 mm).

Valve Springs

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

CAUTIONEnsure valve spring is installed with painted mark facing upward, away from cylinder head.

Valve Stem Oil Seals

Lubricate valve stem oil seal with engine oil. Install valve stem oil seal on top of valve guide. Ensure valve stem oil seal is fully seated.

Valve Guides

  1. Ensure valve guide inside diameter is within specification. See «CYLINDER HEAD»(ref-159232-S11734303692003111900000) table under ENGINE SPECIFICATIONS. Replace valve guide if inside diameter exceeds specification.
  2. To replace valve guide, use hammer, Valve Guide Remover/Installer (SST 09201-10000) and Handle (SST 09950-70010) to drive valve guide out from camshaft side of cylinder head. Measure cylinder head valve guide bore diameter.
  3. If bore diameter is.4325-.4333 in. (10.986-11.006 mm), use standard valve guide. If bore diameter exceeds.4333 in. (11.006 mm), machine valve guide bore to.4344-.4353 in. (11.034-11.057 mm) for oversize valve guide. Replace cylinder head if bore diameter exceeds.4353 in. (11.057 mm). CAUTION: Exhaust valve guide is 1.594 in. (40.49 mm) long, and intake valve guide is 1.516 in. (38.51 mm) long. Ensure proper length valve guide is installed.
  4. To install valve guide, use hammer and valve guide remover/installer. Drive valve guide in from camshaft side of cylinder head.
  5. Using caliper, measure valve guide installed height from top of valve guide to valve spring seat area on cylinder head. (Scheme 30) Valve guide must be installed to appropriate height. See «CYLINDER HEAD»(ref-159232-S11734303692003111900000) table under ENGINE SPECIFICATIONS.
  6. Using.24 in. (6.1 mm) reamer, ream valve guide to obtain specified valve stem-to-guide oil clearance. See «CYLINDER HEAD»(ref-159232-S11734303692003111900000) table under ENGINE SPECIFICATIONS.

Scheme 30

Scheme 30

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.

Valves

Grind valves at 44.5 degree angle. Ensure minimum refinish length, stem diameter and valve margin are within specification. See VALVES & VALVE SPRINGS table under ENGINE SPECIFICATIONS.

Valve Seat Correction Angles

Use 15 degree and 45 degree stones to lower valve seat contact area. Use 75 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.

Fitting Pistons

  1. To determine piston-to-cylinder clearance, measure piston diameter and cylinder bore diameter. Measure piston skirt diameter 1.34 in. (34.0 mm) from top of piston, at 90 degree angle to piston pin bore. See «PISTONS, PINS & RINGS»(ref-159232-S09322368152003111900000) table under ENGINE SPECIFICATIONS.
  2. Measure cylinder bore diameter .39 in. (10.0 mm) from top and bottom of cylinder bore, and at middle of cylinder bore. To determine piston clearance, subtract piston diameter from bore diameter measurement. Replace pistons or cylinder block if clearance is not within specification. See «PISTONS, PINS & RINGS»(ref-159232-S09322368152003111900000) table under ENGINE SPECIFICATIONS.

Piston Rings

Ensure piston ring end gap and side clearance are within specification. See PISTONS, PINS & RINGS table under ENGINE SPECIFICATIONS. Install piston rings with identification mark on compression rings toward top of piston. Position piston ring end gaps in proper locations. (Scheme 31)

Note. No. 1 compression ring is marked with 1T identification mark. No. 2 compression ring is marked with 2T identification mark.

Scheme 31

Scheme 31: Piston Rings

Rod Bearings

  1. Mark connecting rod cap and cylinder number before disassembly. Install connecting rod with front mark toward front of engine. see scheme 23
  2. Using caliper, measure connecting rod bolt diameter about.79 in. (20.1 mm) down from bottom of bolt head. Replace connecting rod bolt if diameter is less than.315 in. (8.00 mm).
  3. Connecting rod cap, rod bearing and crankshaft are stamped with a size mark. (Scheme 32) See «ROD BEARING SPECIFICATIONS»(ref-159232-S35236763022003111900000) table. If replacing rod bearing, ensure size mark on replacement rod bearing is the same as size mark on original rod bearing.
  4. If size mark on original rod bearing cannot be obtained, the size of replacement bearing insert can be determined by adding size mark No. on crankshaft and size mark No. on connecting rod cap together. For example, if size mark on crankshaft is "2" and size mark on connecting rod cap is "1", use rod bearing with size mark "3".
  5. Ensure connecting rod is installed with front mark toward front of engine. see scheme 23 Check connecting rod bearing clearance using Plastigage method. Ensure bearing oil clearance and connecting rod side play are within specification. See «CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS»(ref-159232-S00989288542003111900000) table and «CONNECTING RODS»(ref-159232-S24960226942003111900000) table under ENGINE SPECIFICATIONS.
  6. Before tightening connecting rod bolt to specification, coat bolt threads and bolt head-to-connecting rod cap surface with engine oil. Tighten bolts to specification. See «TORQUE SPECIFICATIONS»(ref-159232-S31757476362003111900000).
Bearing Size MarkThickness - In. (mm)
"1".0590-.0591 (1.499-1.501)
"2".0591-.0592 (1.501-1.504)
"3".0592-.0593 (1.504-1.506)
"4".0593-.0594 (1.506-1.509)
"5".0594-.0596 (1.509-1.512)

ROD BEARING SPECIFICATIONS

Scheme 32

Scheme 32

Crankshaft & Main Bearings

  1. Main bearing caps are numbered on top of cap, with No. 1 main bearing cap at timing belt end of engine and No. 7 at flywheel/drive plate end. Main bearing caps are installed with arrow on top of cap pointing toward timing belt end (front) of engine.
  2. Loosen main bearing cap bolts in sequence using several steps. see scheme 33 Remove main bearing caps, crankshaft and thrust bearings.
  3. Using caliper, measure main bearing cap bolt diameter 2 in. (50 mm) down from bottom of bolt head. Replace main bearing cap bolt if diameter is less than.382 in. (9.70 mm).
  4. Cylinder block and main bearing bore inside diameter are identified by size marks ("0", "1", "2", "3", "4", "5", "6" or "7") stamped on cylinder block. (Scheme 33) Left size mark indicates front or No. 1 bore.
  5. Crankshaft main bearing journal diameter is identified by size mark ("0", "1", "2", "3", "4", "5", "6" or "7") stamped on crankshaft counterweight. (Scheme 33) Ensure journal diameter, taper and out-of-round are within specification. See «CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS»(ref-159232-S00989288542003111900000) table under ENGINE SPECIFICATIONS. Replace crankshaft if not within specification.
  6. Main bearing size mark ("1", "2", "3", "4" or "5") is stamped on back side of main bearing. (Scheme 33) If replacing main bearing, ensure size mark on replacement main bearing is the same as size mark on original main bearing.
  7. If size mark on original main bearing cannot be obtained, use size marks on cylinder block and crankshaft to determine size mark of main bearing. (Scheme 34) Main bearing thickness is determined by size mark. See «MAIN BEARING SPECIFICATIONS»(ref-159232-S29371975622003111900000) table. MAIN BEARING SPECIFICATIONS Bearing Size Mark Thickness - In. (mm) "1".0785-.0786 (1.994-1.997) "2".0786-.0787 (1.997-2.000) "3".0787-.0789 (2.000-2.003) "4".0789-.0790 (2.003-2.006) "5".0790-.0791 (2.006-2.009)
  8. Use Plastigage to check main bearing oil clearance. Coat threads and seat area of main bearing cap bolt with engine oil before installing. Install.905 in. (22.98 mm) wide main bearings in No. 1 (timing belt end) main bearing and narrow main bearings in all other locations.
  9. Ensure main bearings with oil holes are aligned with oil galleries in cylinder block. Lower main bearings, installed in main bearing caps, do not have oil holes.
  10. Install thrust bearings on No. 4 main bearing in cylinder block and main bearing cap, with grooved sides facing outward, toward crankshaft. Install crankshaft and main bearing caps. CAUTION: 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. 7 at flywheel/drive plate end.
  11. Install and tighten main bearing cap bolts to specification in sequence using several steps. see scheme 33 See «TORQUE SPECIFICATIONS»(ref-159232-S31757476362003111900000).
  12. Ensure crankshaft end play and main bearing oil clearance are within specification. See «CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS»(ref-159232-S00989288542003111900000) table. Replace thrust bearing if end play is not within specification.

Scheme 33

Scheme 33

Scheme 34

Scheme 34

Thrust Bearing

Install thrust bearing on No. 4 main bearing with grooves toward crankshaft (away from cylinder block). Replace thrust bearing if crankshaft end play is not within specification. See CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS table under ENGINE SPECIFICATIONS.

Cylinder Block

  1. Inspect cylinder block deck surface warpage. Replace cylinder block if deck warpage exceeds specification. See «CYLINDER BLOCK»(ref-159232-S35156272552003111900000) table under ENGINE SPECIFICATIONS.
  2. Measure cylinder bore diameter.39 in. (10 mm) from top and bottom of cylinder bore, and at middle of cylinder bore. Replace cylinder block if cylinder bore diameter is not within specification. See «CYLINDER BLOCK»(ref-159232-S35156272552003111900000) table under ENGINE SPECIFICATIONS.
  3. Install main bearing caps and tighten bolts to specification in sequence. see scheme 33 Ensure main bearing bore inside diameter is within specification. See «CYLINDER BLOCK»(ref-159232-S35156272552003111900000) table under ENGINE SPECIFICATIONS.

Note. Main bearing bore inside diameter is determined by size mark ("0", "1", "2", "3", "4", "5", "6" or "7") stamped on cylinder block. (Scheme 33)

Oil Pressure

With engine at normal operating temperature, oil pressure should be at least 7.0 psi (0.5 kg/cm 2 ) at idle, and about 47 psi (3.3 kg/cm 2 ) at 3000 RPM.

OIL PUMP

Note. Manufacturer lists procedure with engine removed.

CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS

ApplicationIn. (mm)
Crankshaft
End Play
Standard.0008-.0087 (.020-.221)
Wear Limit.0118 (.300)
Runout.0024 (.060)
Main Bearings
Journal Diameter (1)
Size Mark "0"2.44086-2.44094 (61.9978-62.0000)
Size Mark "1"2.44078-2.44086 (61.9958-61.9978)
Size Mark "2"2.44070-2.44078 (61.9937-61.9958)
Size Mark "3"2.44063-2.44070 (61.9920-61.9937)
Size Mark "4"2.44055-2.44063 (61.9989-61.9920)
Size Mark "5"2.44047-2.44055 (61.9879-61.9899)
Size Mark "6"2.44039-2.44047 (61.9859-61.9879)
Size Mark "7"2.44031-2.44039 (61.9838-61.9859)
Journal Out-Of-Round.0008 (.020)
Journal Taper.0008 (.020)
Oil Clearance
Standard Crankshaft
Standard.0010-.0016 (.025-.041)
Wear Limit.0024 (.060)
Undersize Crankshaft (.010 in. - .25 mm)
Standard.0010-.0024 (.025-.060)
Wear Limit.0031 (.080)
Crankpin
Journal Diameter (2)
Size Mark "0"2.0470-2.0472 (51.994-52.000)
Size Mark "1"2.0468-2.0470 (51.988-51.994)
Size Mark "2"2.0465-2.0468 (51.981-51.988)
Journal Out-Of-Round.0008 (.020)
Journal Taper.0008 (.020)
Oil Clearance
Standard Crankshaft
Standard.0009-.0016 (.023-.041)
Wear Limit.0027 (.070)
.010 in. (.25 mm) Undersize Crankshaft
Standard.0011-.0026 (.028-.066)
Wear Limit.0031 (.080)
(1) Main bearing journal diameter is determined by size mark stamped on crankshaft. (Scheme 33) (2) Rod journal diameter is determined by size mark stamped on crankshaft. (Scheme 32)
(1)Main bearing journal diameter is determined by size mark stamped on crankshaft. (Scheme 33)
(2)Rod journal diameter is determined by size mark stamped on crankshaft. (Scheme 32)

CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS

CONNECTING RODS

ApplicationIn. (mm)
Bore Diameter
Pin Bushing Bore.8663-.8667 (22.004-22.014)
Crankpin Bore (1)
Size Mark "1"2.1663-2.1666 (55.024-55.032)
Size Mark "2"2.1666-2.1668 (55.032-55.037)
Size Mark "3"2.1668-2.1670 (55.037-55.041)
Maximum Bend.0020 Per 3.94 (.050 Per 100.0)
Maximum Twist.0059 Per 3.94 (.150 Per 100.0)
Side Play
Standard.0098-.0158 (.250-.401)
Wear Limit.0197 (.500)
(1) Bore diameter is determined by size mark stamped on connecting rod cap. (Scheme 32)
(1)Bore diameter is determined by size mark stamped on connecting rod cap. (Scheme 32)

CONNECTING RODS

ENGINE PISTONS, ENGINE PISTON PINS & ENGINE PISTON RINGS

ApplicationIn. (mm)
Pistons
Oil Clearance
Standard.0014-.0027 (.035-.068)
Wear Limit.0039 (.100)
Diameter3.3837-3.3844 (85.945-85.965)
Pins
Diameter.8660-.8664 (21.996-22.007)
Piston Fit(1)
Rod Fit
Standard.0002-.0004 (.005-.012)
Wear Limit.002 (.05)
Rings
No. 1
End Gap
Standard.0118-.0185 (.300-.470)
Maximum.0421 (1.069)
Side Clearance.0004-.0028 (.010-.071)
No. 2
End Gap
Standard.0138-.0205 (.350-.520)
Maximum.0441 (1.120)
Side Clearance.0012-.0028 (.030-.071)
No. 3 (Oil)
End Gap
Standard.0051-.0177 (.130-.450)
Wear Limit.0413 (1.050)
(1) With piston at 176°F (80°C), piston pin should be able to be pressed into piston using thumb pressure.
(1)With piston at 176°F (80°C), piston pin should be able to be pressed into piston using thumb pressure.

ENGINE PISTONS, ENGINE PISTON PINS & ENGINE PISTON RINGS

ApplicationIn. (mm)
Cylinder Bore
Standard Diameter3.3858-3.3863 (86.000-86.012)
Maximum Diameter3.3866 (86.020)
Main Bearing Bore Inside Diameter (1)
Size Mark "0"2.59922-2.59929 (66.0202-66.0220)
Size Mark "1"2.59929-2.59937 (66.0220-66.0240)
Size Mark "2"2.59937-2.59944 (66.0240-66.0258)
Size Mark "3"2.59944-2.59952 (66.0258-66.0278)
Size Mark "4"2.59952-2.59960 (66.0278-66.0300)
Size Mark "5"2.59960-2.59968 (66.0300-66.0320)
Size Mark "6"2.59968-2.59976 (66.0320-66.0340)
Size Mark "7"2.59976-2.59984 (66.0340-66.0360)
Maximum Deck Warpage.0028 (.071)
(1) Cylinder block main bearing bore inside diameter is determined by size mark stamped on cylinder block. (Scheme 33)
(1)Cylinder block main bearing bore inside diameter is determined by size mark stamped on cylinder block. (Scheme 33)

CYLINDER BLOCK

VALVES & VALVE SPRINGS

ApplicationSpecification
Intake Valves
Face Angle44.5°
Minimum Margin.020 in. (.50 mm)
Minimum Refinish Length3.8657 in. (98.190 mm)
Stem Diameter.2350-.2356 in. (5.970-5.985 mm)
Stem-To-Guide Oil Clearance
Standard.0010-.0024 in. (.025-.061 mm)
Wear Limit.0031 in. (.080 mm)
Exhaust Valves
Face Angle44.5°
Minimum Margin.020 in. (.50 mm)
Minimum Refinish Length3.8874 in. (98.740 mm)
Stem Diameter.2348-.2354 in. (5.964-5.980 mm)
Stem-To-Guide Oil Clearance
Standard.0012-.0026 in. (.030-.066 mm)
Wear Limit.0039 in. (.100 mm)
Valve Springs
Free Length
Pink Paint Mark1.7209 in. (43.71 mm)
Yellow Paint Mark1.7362 in. (44.10 mm)
Out-Of-Square.079 in. (2.01 mm)
Lbs. @ In. (kg @ mm)
Pressure
Intake & Exhaust42-46 @ 1.358 (19-21 @ 34.52)

VALVES & VALVE SPRINGS

ApplicationSpecification
Maximum Warpage
Cylinder Block Surface.0039 in. (.100 mm)
Manifold Surface.0039 in. (.100 mm)
Valve Seats
Intake
Seat Angle45 degrees
Seat Width.039-.055 in. (1.00-1.40 mm)
Exhaust
Seat Angle45 degrees
Seat Width.047-.063 in. (1.19-1.60 mm)
Valve Guides
Intake Valve
Valve Guide Cylinder Head Bore I.D.
Standard Valve Guide.4325-.4333 in. (10.986-11.006 mm)
Oversize Valve Guide.4344-.4353 in. (11.034-11.057 mm)
Valve Guide I.D..2366-.2374 in. (6.010-6.030 mm)
Valve Guide Installed Height.484-.500 in. (12.30-12.70 mm)
Valve Stem-To-Guide Oil Clearance
Standard.0010-.0024 in. (.025-.061 mm)
Wear Limit.0031 in. (.080 mm)
Exhaust Valve
Valve Guide Cylinder Head Bore I.D.
Standard Valve Guide.4325-.4333 in. (10.986-11.006 mm)
Oversize Valve Guide.4344-.4353 in. (11.034-11.057 mm)
Valve Guide I.D..2366-.2374 in. (6.010-6.030 mm)
Valve Guide Installed Height.449-.465 in. (11.40-11.81 mm)
Valve Stem-To-Guide Oil Clearance
Standard.0012-.0026 in. (.030-.066 mm)
Wear Limit.0039 in. (.100 mm)

CYLINDER HEAD

ApplicationIn. (mm)
End Play
Standard.0031-.0075 (.080-.190)
Wear Limit.0118 (.300)
Journal Diameter1.1397-1.1404 (28.948-28.966)
Journal Runout.0031 (.080)
Lobe Height
Intake
Standard1.7445-1.7465 (44.310-44.361)
Wear Limit1.7386 (44.160)
Exhaust
Standard1.7421-1.7461 (44.250-44.350)
Wear Limit1.7362 (44.10)
Journal Oil Clearance
Standard.0014-.0028 (.035-.071)
Wear Limit.0039 (.100)

CAMSHAFT

ApplicationIn. (mm)
Bore Diameter1.2205-1.2211 (31.000-31.016)
Lifter Diameter1.2191-1.2195 (30.965-30.976)
Oil Clearance
Standard.0009-.0020 (.023-.050)
Wear Limit.0028 (.071)

VALVE LIFTERS