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VTEC Rocker Arm Test

NOTE: Special tools required:
  • VTEC Air Adapter (07VAJ-P8A010A)
  • VTEC Air Stopper (070AJ-0030100)
  • Air Pressure Regulator (07AAJ-PNAA100)
  1. Start engine and let run for 5 minutes, then turn ignition off.
  2. Remove intake manifold. See INTAKE MANIFOLD REMOVAL & INSTALLATION in ENGINES article.
  3. Remove valve covers.
  4. Set No. 1 piston on TDC.
  5. Push on the intake mid rocker arm (A) for No. 1 cylinder. See (a) in Fig 1 . The mid rocker arm should move independently of the primary rocker arm (B) and secondary rocker arm (C). If intake mid rocker arm (A) does not move independently remove rocker arms as an assembly, then check that the pistons in mid rocker arm (A) and primary rocker arm (B) move smoothly. If any rocker arm needs replacing, replace primary, mid and secondary rocker arms as an assembly and retest. If mid rocker arm moves freely, go to next step.
  6. Repeat step  5 on the remaining mid rocker arms with each piston on TDC. When all are checked and pass, go to next step.
  7. Ensure shop air compressor indicates over 100 psi (690 kPa). Go to next step.
  8. Inspect valve clearances.
  9. Remove No. 1 and No. 5 intake rocker shaft mounting bolts. Install and connect the special tools as shown. See (b) in Fig 1 .
  10. Loosen the valve on regulator and apply specified air pressure: 64-78 psi (440-540 kPa).
    NOTE: If the synchronizing pistons do not move after applying air pressure, move primary and secondary rocker arm up and down manually.
  11. Ensure the intake primary rocker arm (A) and intake secondary rocker arm (B) are mechanically connected to piston and mid rocker arm (C) does not move when pushed manually. See (c) in Fig 1 . If any intake mid rocker arm (C) move independently of the primary rocker arm (A) and secondary rocker arm (B), replace rocker arms as a set.
  12. Remove tools. Tighten rocker shaft bolts to 17 ft. lbs. (24 N.m). Reinstall valve covers and intake manifold.
Fig 1: VTEC Rocker Arm Test Steps Illustrated
G00188372Courtesy of AMERICAN HONDA MOTOR CO., INC.