Contents Section: Mechanical All sections

Engine Mechanical - 3.4L: Other Toyota Tacoma I рестайлинг

Mechanical 4 illustrations ~1939 words

FUEL PRESSURE RELEASE

  1. Disconnect electrical connector from top of electric fuel pump. Electric fuel pump is located in fuel tank with electrical connector located on top of fuel tank.
  2. Start engine and allow engine to idle until engine stalls. Turn ignition off. Reconnect electrical connector for electric fuel pump. Disconnect negative battery cable.
  3. Place suitable container under fuel line connection. Cover fuel line connection with shop towel. Slowly loosen fuel line connection, allowing fuel pressure to be released. Once fuel pressure is released, fuel system components may be serviced.

CAMSHAFT

Note. When servicing camshafts, reference to right and left components are as viewed from rear (flywheel end) of engine.

Cylinder Head

  1. Thoroughly clean cylinder head of carbon and gasket material. Inspect cylinder head warpage at cylinder block and manifold surfaces. Replace cylinder head if warpage exceeds specification. See «CYLINDER HEAD»(ref-159020-S28559498202003110600000) table under ENGINE SPECIFICATIONS. Use dye penetrant spray to check for cracks.
  2. To check camshaft oil clearance using Plastigage, install camshaft in cylinder head using proper procedure. See «CAMSHAFT»(ref-159020-S35522861772003110600000) .
  3. Replace camshaft and/or cylinder head if oil clearance is not within specification. See «CAMSHAFT»(ref-159020-S34710783562003110600000) table under ENGINE SPECIFICATIONS.
  4. Check camshaft end play with camshaft bearing cap bolts tightened to specification. Replace camshaft and/or cylinder head if camshaft end play is not within specification. See «CAMSHAFT»(ref-159020-S34710783562003110600000) table under ENGINE SPECIFICATIONS.
  5. Measure valve lifter diameter and lifter bore diameter. Ensure oil clearance is within specification. Replace components if not within specification. See «VALVE LIFTERS»(ref-159020-S23514108722003110600000) table under ENGINE SPECIFICATIONS.
  6. If installing spark plug tubes in NEW cylinder head, apply sealant on cylinder head end of spark plug tube. Using press, install spark plug tube until distance between top surface of spark plug tube and camshaft bearing cap surface on cylinder head is 1.929-1.945 in. (48.99-49.40 mm).

Valve Springs

Ensure valve spring free length, pressure and out-of-square are within specification. See VALVES & VALVE SPRINGS table under ENGINE SPECIFICATIONS. Replace valve spring if not within specification.

CAUTIONIntake valve stem oil seal is Silver colored on top of oil seal and exhaust valve stem oil seal is Black colored on top of oil seal. Ensure proper valve stem oil seal is installed.

Valve Stem Oil Seals

Lubricate valve stem oil seal with engine oil. Install valve stem oil seal using oil seal installer.

Valve Guides

  1. Ensure valve guide inside diameter is within specification. See «CYLINDER HEAD»(ref-159020-S28559498202003110600000) table under ENGINE SPECIFICATIONS. Replace valve guide if inside diameter exceeds specification.
  2. To replace valve guide, wrap tape around stem of an old valve, about .315 in. (8.00 mm) from end of valve stem. From top of cylinder head, insert old valve into valve guide until tape area rests on valve guide.
  3. Using hammer, hit old valve to break off top of old valve guide. Remove snap ring from valve guide. Heat cylinder head to 176-212°F (80-100°C). Using hammer and valve guide remover/installer, drive valve guide from camshaft side of cylinder head.
  4. Measure cylinder head valve guide bore inside diameter. If bore inside diameter is .4325-.4341 in. (10.985-11.026 mm), use standard valve guide. If bore inside diameter is .4350-.4361 in. (11.049-11.076 mm), use oversize valve guide.
  5. If bore inside diameter exceeds .4341 in. (11.026 mm), machine valve guide bore to .4350-.4361 in. (11.049-11.076 mm) for oversize valve guide. If bore I.D. exceeds .4361 in. (11.076 mm), replace cylinder head.
  6. To install valve guide, heat cylinder head to 176-212°F (80-100°C). Using hammer and valve guide remover/installer, drive valve guide in from camshaft side of cylinder head until snap ring on valve guide contacts cylinder head.
  7. Using .236 in. (5.99 mm) reamer, ream valve guide to obtain specified valve stem-to-guide oil clearance. See «CYLINDER HEAD»(ref-159020-S28559498202003110600000) 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.

Valves

Ensure minimum refinish length, stem diameter and valve margin are within specification. See VALVES & VALVE SPRINGS table under ENGINE SPECIFICATIONS. Replace valve if not within specification.

Valve Seat Correction Angles

Use 30 degree and 45 degree stone to lower valve seat contact area. 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. Replace components if not within specification.

Fitting Pistons

  1. Different piston sizes and cylinder bore sizes are used. Piston diameter is determined by size mark ("1", "2" or "3") stamped on top of piston. see scheme 29 Cylinder bore diameter is determined by cylinder bore size mark ("1", "2" or "3") on cylinder block deck surface. (Scheme 72)
  2. To determine piston-to-cylinder bore clearance, measure piston diameter and cylinder bore diameter. Measure piston skirt diameter at 1.02 in. (25.9 mm) from top of piston at 90 degree angle to piston pin. Measure cylinder bore diameter at 2 different places, 90 degrees apart at.39 in. (9.9 mm) from top and bottom of cylinder bore and at middle of cylinder bore.
  3. Ensure piston diameter and cylinder bore diameter are within specification. See «PISTONS, PINS & RINGS»(ref-159020-S31948800002003110600000) table and «CYLINDER BLOCK»(ref-159020-S14356824512003110600000) table under ENGINE SPECIFICATIONS.
  4. Calculate piston-to-cylinder clearance. Replace pistons or bore cylinder block for oversize pistons if clearance exceeds specification. See «PISTONS, PINS & RINGS»(ref-159020-S31948800002003110600000) table under ENGINE SPECIFICATIONS. Pistons are available in.020 in. (.50 mm) oversize. If replacing piston, ensure replacement piston contains same size mark as cylinder bore size mark on cylinder block.

Scheme 72

Scheme 72

Piston Rings

Ensure piston ring end gap and side clearance are within specification. See PISTONS, PINS & RINGS table under ENGINE SPECIFICATIONS. Position piston rings with ring end gaps in proper areas and with identification mark on piston ring toward top of piston. (Scheme 73)

Note. No. 1 compression ring may contain a 1R or "T" identification mark and No. 2 compression ring may contain a 2R or 2T identification mark. Ensure proper ring is installed in correct location.

Scheme 73

Scheme 73: Piston Rings

Rod Bearings

  1. Ensure connecting rod and connecting rod cap are marked with matching cylinder number for installation reference. Piston and connecting rod and connecting rod cap must be installed in cylinder block with front mark facing timing belt end of engine. see scheme 29
  2. Connecting rod cap and rod bearing are stamped with size mark ("1", "2" or "3"). (Scheme 74) Size marks on connecting rod cap and rod bearing must be the same. Rod bearing thickness is determined by size mark. See «ROD BEARING SPECIFICATIONS»(ref-159020-S10831501062003110600000) table. NOTE: If replacing rod bearing, ensure size mark on replacement rod bearing is the same as size mark on original rod bearing. Size mark must also be the same as that stamped on connecting rod cap.
  3. Ensure nut rotates easily on connecting rod bolt. If nut does not rotate easily, use caliper to measure outside diameter of connecting rod bolt at threaded area.59 in. (14.9 mm) from end of connecting rod bolt. Replace connecting rod with connecting rod bolt and nut as an assembly if outside diameter is less than.2992 in. (7.599 mm).
  4. Ensure piston and connecting rod are installed in cylinder block with front mark on piston, and front mark (protrusion) on connecting rod cap facing timing belt end of engine. see scheme 29
  5. Coat threads of connecting rod bolts and nut-to-connecting rod cap contact surface with engine oil before tightening to specification. See «TORQUE SPECIFICATIONS»(ref-159020-S42029834072003110600000).
  6. Ensure bearing oil clearance and connecting rod side play are within specification. See «CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS»(ref-159020-S02825134572003110600000) table and «CONNECTING RODS»(ref-159020-S29343063272003110600000) table under ENGINE SPECIFICATIONS.
Bearing Size MarkThickness - In. (mm)
"1".0584-.0586 (1.483-1.488)
"2".0586-.0587 (1.488-1.490)
"3".0587-.0589 (1.490-1.496)

ROD BEARING SPECIFICATIONS

Scheme 74

Scheme 74

Crankshaft & Main Bearings

  1. Note direction of front mark (arrow) on main cap for reassembly reference. see scheme 39
  2. Remove main bearing cap bolts in sequence using several passes. see scheme 39 Remove main bearing cap, crankshaft, main bearings and thrust bearings.
  3. Cylinder block main bearing bore inside diameter is determined by main bearing bore size mark ("1", "2" or "3") stamped on rear of cylinder block. (Scheme 75) Crankshaft main bearing journal diameter is determined by main bearing journal size mark ("0", "1" or "2") located on crankshaft counterweight. (Scheme 75)
  4. Ensure journal diameter, taper and out-of-round are with within specification. See «CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS»(ref-159020-S02825134572003110600000) table under ENGINE SPECIFICATIONS.
  5. Main bearing size mark ("1", "2", "3", "4" or "5") is located on side of main bearing. (Scheme 75) If replacing main bearing, ensure size mark on replacement main bearing is the same as size mark on original main bearing.
  6. If main bearing size mark on original main bearing cannot be obtained, add main bearing bore size mark on cylinder block and main bearing journal size mark on crankshaft together to determine size mark of main bearing to be used. For example, if cylinder block contains a main bearing bore size mark of "2" and crankshaft journal has a size mark of "1", use a main bearing with the size mark of "3". Main bearing thickness is determined by main bearing size mark. See «MAIN BEARING SPECIFICATIONS»(ref-159020-S35654760282003110600000) table. MAIN BEARING SPECIFICATIONS Size Mark Bearing Thickness - In. (mm) No. 1 Main Bearing "1".07838-.07850 (1.991-1.994) "2".07850-.07862 (1.994-1.997) "3".07862-.07874 (1.997-2.000) "4".07874-.07885 (2.000-2.003) "5".07885-.07897 (2.003 2.006) Except No. 1 Main Bearing "1".07830-.07842 (1.989-1.992) "2".07842-.07854 (1.992-1.995) "3".07854-.07866 (1.995-1.998) "4".07866-.07877 (1.998-2.001) "5".07877-.07889 (2.001-2.004)
  7. Use Plastigage to check main bearing oil clearance. Coat threads of main bearing cap bolts and bolt head-to-main bearing cap area with engine oil.
  8. Install.87 in. (22.0 mm) wide main bearings in No. 1 main bearing at timing belt end of engine and.79 in. (20.0 mm) wide bearings in all other main bearings. Ensure all main bearings with oil holes are installed in cylinder block and lower main bearings installed in main bearing cap DO NOT have oil holes. CAUTION: Main bearing cap must be installed with front mark (arrow) on top of cap pointing toward timing belt end of engine. see scheme 39
  9. Install thrust bearings on No. 2 main bearing in cylinder block and main bearing cap with grooved sides facing outward, toward crankshaft. Install crankshaft and main bearing cap.
  10. Install and tighten main bearing cap bolts to specification in sequence using several steps. see scheme 39 See «TORQUE SPECIFICATIONS»(ref-159020-S42029834072003110600000).
  11. Ensure crankshaft end play and main bearing oil clearance are within specification. See «CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS»(ref-159020-S02825134572003110600000) table under ENGINE SPECIFICATIONS. Replace thrust bearing if crankshaft end play is not within specification.

Scheme 75

Scheme 75

Thrust Bearing

Install thrust bearings on No. 2 main bearing in cylinder block and main bearing cap with grooved sides facing outward, toward crankshaft. 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-159020-S14356824512003110600000) table under ENGINE SPECIFICATIONS.
  2. Different cylinder bore sizes are used. Cylinder bore diameter is determined by cylinder bore size mark ("1", "2" or "3") on cylinder block deck surface. (Scheme 72)
  3. Measure cylinder bore diameter at 2 different places, 90 degrees apart at.39 in. (9.9 mm) from top and bottom of cylinder bore and at middle of cylinder bore. Ensure cylinder bore diameter is within specification. See «CYLINDER BLOCK»(ref-159020-S14356824512003110600000) table under ENGINE SPECIFICATIONS.
  4. Bore cylinder block for oversize pistons if cylinder bore diameter exceeds specification. Pistons are available in.020 in. (.50 mm) oversize.
  5. Ensure main bearing bore inside diameter is within specification with main bearing cap installed and bolts tightened to specification. See «CYLINDER BLOCK»(ref-159020-S14356824512003110600000) table under ENGINE SPECIFICATIONS. See «TORQUE SPECIFICATIONS»(ref-159020-S42029834072003110600000).

Note. Main bearing bore inside diameter is determined by main bearing bore size mark ("1", "2" or "3") stamped on rear of cylinder block. (Scheme 75)

Oil Pressure

With engine at normal operating temperature, oil pressure should be at least 4.3 psi (0.3 kg/cm 2 ) at idle and 36-75 psi (2.5-5.2 kg/cm 2 ) at 3000 RPM.