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Valve Clearance: RX300

  1. Outer cowl top panel must be removed. See Fig 1. Remove windshield wiper arm nuts and windshield wiper arms assemblies. Place protective tape along bottom of windshield to protect windshield. Remove cowl top seal.
  2. Remove driver's side and passenger's side ventilation louvers. See Fig 1. Disconnect electrical connector for wiper motor. Remove bolts and wiper motor with wiper link assembly. Remove bolts and outer cowl top panel.
    Fig 1: Locating Outer Cowl Top Panel & Components (RX300)
    G99D50412Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. Remove suspension upper brace. Suspension upper brace fits between strut towers and is bolted to top of each strut tower.
  4. Remove passenger's side front fender apron for access to crankshaft pulley. Drain cooling system. Remove intake manifold cover. See Figure.
  5. Air intake chamber must be removed for removal of valve covers. Remove air cleaner cap assembly and air filter. Disconnect necessary electrical connections, control cables, PCV hose, coolant hoses, ground cables and vacuum hoses for removal of air intake chamber. See Figure.
  6. Remove nuts and disconnect power steering pressure tube from No. 1 engine hanger. See Figure. Remove bolts, No. 1 engine hanger and throttle body brace. See Figure.
  7. Remove bolts/nuts, air intake chamber and gasket. Disconnect electrical connectors at ignition coils. Remove bolts and ignition coils. Disconnect upper radiator hose from coolant outlet at front of engine, between cylinder heads.
  8. Disconnect electrical connectors for removal of wiring assemblies located above valve covers. Remove bolts/nuts and wiring assemblies. Remove bolts, valve covers and gaskets.
  9. Rotate crankshaft pulley clockwise (viewed from front of engine) so crankshaft pulley timing mark (groove) aligns with "0" mark on timing belt cover and cylinder No. 1 is at TDC on compression stroke. Cylinder No. 1 is front cylinder on right side of engine when viewed from flywheel end of engine. See Figure.
  10. Ensure cylinder No. 1 intake and exhaust valve lifters are loose. If valve lifters are not as described, rotate crankshaft clockwise one full revolution (360 degrees) and realign crankshaft pulley timing mark (groove) with "0" mark on timing belt cover.
  11. Using feeler gauge, measure valve clearance between valve lifter and camshaft on intake valves on cylinders No. 1 and 6, and exhaust valves on cylinders No. 2 and 3. Perform STEP 1. See Figure. Record valve clearance.
  12. Rotate crankshaft pulley clockwise an additional 240 degrees (2/3 revolution). Measure valve clearance of intake valves on cylinders No. 2 and 3, and exhaust valves on cylinders No. 4 and 5. Perform STEP 2. See Figure. Record valve clearance.
  13. Rotate crankshaft pulley clockwise an additional 240 degrees (2/3 revolution). Measure valve clearance of intake valves on cylinders No. 4 and 5, and exhaust valves on cylinders No. 1 and 6. Perform STEP 3. See Figure. Record valve clearance.
  14. Ensure valve clearance is within specification. See VALVE CLEARANCE SPECIFICATIONS (RX300)  table.
    VALVE CLEARANCE SPECIFICATIONS (RX300)

    Application (1) In. (mm)
    Intake .006-.010 (.15-.25)
    Exhaust .010-.014 (.25-.35)
    (1) Adjust valve clearance with engine cold.
  15. If valve clearance adjustment is required, rotate crankshaft pulley so camshaft lobe on valve to be adjusted is facing upward, away from valve lifter. Rotate valve lifter so notch area on valve lifter is at 90-degree angle to camshaft. This will place notch area perpendicular to camshaft.
  16. Valve Clearance Adjuster (SST 09248-55040) is used to remove adjusting shim. Using SST "A" of valve clearance adjuster, press valve lifter downward. See Figure. Install SST "B" between camshaft and valve lifter with side marked with "7" or "9" in the proper location, depending on cylinder application. See Figure. Side marked with "7" should be used on front valves on cylinders No. 1 and 2 only. Side marked with "9" should be used on all except front valves on cylinders No. 1 and 2. Remove SST "A".
  17. Using small screwdriver and magnet, remove adjusting shim. Using micrometer, measure and record thickness of removed adjusting shim. Using measured clearance and adjusting shim thickness, determine correct thickness of adjusting shim to be used. See Figure and Figure .
  18. Install replacement adjusting shim with imprinted numbers on adjusting shim facing downward, toward valve lifter. Using SST "A", press downward on valve lifter and remove SST "B". Recheck valve clearance.
  19. If spark plug tube gasket in valve cover requires replacement, bend gasket retaining tab upward. Pry spark plug tube gasket from valve cover. Use care not to scratch valve cover sealing surface.
  20. Using hammer and proper sized bushing driver, tap spark plug tube gasket into valve cover until spark plug tube gasket is even with valve cover surface. Bend retaining tab downward. Coat spark plug tube gasket sealing area with grease.
  21. Before installing valve covers and gaskets, apply sealant at specified areas on cylinder head. See Figure. Install gasket and valve cover. Install and tighten valve cover bolts to specification. See TORQUE SPECIFICATIONS . To install remaining components, reverse removal procedure using NEW gaskets. Tighten bolts/nuts to specification. See TORQUE SPECIFICATIONS . Fill cooling system.
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