Mazda 323/626/929/GLC/MX-6/RX-7 1978-1989



See Figure 1


  1. Disconnect the negative battery cable. Drain the cooling system.
  3. Disconnect the hoses from the air pump and remove the air pump from the engine.
  5. Loosen the hose clamps, then disconnect the funnel and air hose from the air cleaner and the turbocharger. Remove the air funnel and air hose from the engine.

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Fig. Fig. 1: Twin-scroll turbocharger system used on the 1986-89 RX-7

  1. Disengage the connector from the air control valve and remove the valve from the engine.
  3. Disconnect the split air pipe from the engine and remove the pipe, along with the gasket.
  5. Disconnect and remove the water hose and water pipe from the engine.
  7. Disconnect the supply and return oil pipes from the turbocharger. (There may be some oil left in the lines, so be prepared to collect any residual oil with a small plastic container. Be sure to cover the openings to protect the system.)
  9. Remove the front converter insulator covers and disconnect the front converter from the turbocharger. Remove and discard the old gasket.
  11. Unstake the retainer tabs from the retainer plate with a small prying tool. Remove the nuts and washers that secure the turbocharger to the exhaust manifold studs, then remove the turbocharger from the engine. Immediately cover all the turbo openings to prevent the entry of dirt and foreign matter. Remove and discard the old turbocharger gasket.
  13. Remove the insulator covers from the exhaust manifold. Loosen and remove the exhaust manifold retaining nuts/lockwashers.
  15. Remove the exhaust manifold and waste gate actuator assembly from the engine. Remove the gasket and discard it.
  17. Thoroughly clean the exhaust manifold and turbocharger contact surfaces, then check the exhaust manifold for warpage with a metal straightedge.

To install:
  1. Place a new manifold gasket onto the engine. Install the exhaust manifold/actuator assembly over the mounting studs and position it flush with the gasket. Install the lockwashers and mounting nuts, then torque them to 23-34 ft. lbs. (31-46 Nm).
  3. Install a new turbocharger gasket onto the exhaust manifold, then carefully guide the turbo over the mounting studs and onto the gasket. Install the mounting nuts/lockwashers. Torque the mounting nuts to 33-40 ft. lbs. (45-54 Nm). Once the nuts are torqued, crimp the tabs on the nut retaining plate to prevent the nuts from loosening. Remove the protective covers from the turbo openings.
  5. Connect the front converter to the turbocharger with a new gasket. Torque the nuts to 33-40 ft. lbs. (45-54 Nm).
  7. Install the remaining components in reverse of the removal procedure. Install a new gasket for any part requiring one:

    Insulator covers
    Oil pipes
    Water pipe and water hose
    Split air pipe
    Air control valve
    Air funnel and air hose
    Air pump and air hoses

  9. Fill the cooling system to the proper level with a suitable coolant mixture and connect the negative battery cable.
  11. Start the engine and check for leaks. Make all necessary adjustments.