Ford Mustang 1989-1993 Repair Guide

Fixed Orifice Tube



See Figure 1

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Fig. Fig. 1: Fixed orifice tube replacement

The fixed orifice tube should be replaced whenever the compressor is replaced. If high pressure reads extremely high and low pressure (suction) is almost a vacuum, the fixed orifice is plugged and must be replaced.If replacement of the fixed orifice tube is necessary, the liquid line must be replaced or install orifice tube replacement kit E5VY-190695-A or equivalent.

  1. Discharge the refrigerant from the air conditioning system according the to proper procedure.
  3. Remove the liquid line from the vehicle.
  5. Locate the orifice tube by the three indented notches or a circular depression in the metal portion of the liquid line.
  7. Note the angular position of the ends of the liquid line so it can be reassembled in the correct position.
  9. Cut a 2 1 / 2 in. (63.5mm) section from the tube at the orifice tube location. Do not cut closer than 1 in. (25mm) from the start of a bend in the tube.
  11. Remove the orifice tube from the housing with pliers. The orifice tube removal tool cannot be used.

To install:
  1. Flush the two pieces of liquid line to remove any contaminants.
  3. Lubricate the O-rings with clean refrigerant oil and assemble the orifice tube kit, with the orifice tube installed, to the liquid line. Make sure the flow direction arrow is pointing toward the evaporator end of the liquid line and the taper of each compression ring is toward the compression nut.

The inlet tube will be positioned against the orifice tube tabs when correctly assembled.

  1. While holding the hex of the tube in a suitable vise, tighten each compression nut to 65-70 ft. lbs. (88-94 Nm) with a crow foot wrench.
  3. Install the liquid line on the vehicle using new O-rings lubricated with clean refrigerant oil.
  5. Leak test, evacuate and charge the system. Observe all safety precautions.
  7. Check the system for proper operation.