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How to Install a Moroso Air/Oil Separator on Your 1996-2004 Mustang GT

Installation Time

30 minutes

American Muscle
Shop Parts in this Guide

Installation

  • (1) TANK BODY
  • (1) BILLET CLAMP
  • (1) BALL VALVE
  • (1) 90 DEGREE DRAIN
  • (1) STAINLESS STEEL BRACKET
  • (2) 90 DEGREE BARBED FITTINGS
  • (1) LENGTH OF ½” TUBE
  • (1) DRAIN CAP
  • (2) ¼ X 20 SHCS X 5/8
  • (1) ¼ X 20 SHCS X 1
  • (1) 8mm Nut
  • (1) ½” – 5/8” COUPLING
  • (1) LENGTH OF 5/8” TUBE

Step 1: Loosen Air Intake hose clamps


Step 2: Remove lines from Air Intake hose


Step 3: Remove Air Intake hose from throttle body


Step 4: Remove Air Intake hose from Air Cleaner Box, and remove from vehicle


Step 5: Locate PCV Tube (Valve cover Side)


Step 6: Remove tube from PCV Valve


Step 7: Locate PCV Tube (Intake Side)


Step 8: Remove from Intake


Step 9: Remove PCV tube from Vehicle and put a side


Step 10: Assemble Billet mount to Stainless Bracket as shown. Note orientation of ¼” SHCS


Step11: Locate 8mm stud as shown and install Billet Stainless Mount


Step 12: Assemble Air Oil Separator as shown, apply Teflon Tape to all fittings


Stap13: Insert Air Oil Separator into billet clamp, line up seam on Air Oil Separator to top of Billet Clamp and tighten


Step 14: cut 1 pc of ½” hose to 34”


Step 15: Insert one end of ½” hose to rear fitting on Air Oil Separator


Step 16: Route ½” hose from Air Oil Separator to Valve Cover as shown


Step 17: Remove 90 degree fitting from PCV tube previously removed


Step 18: Insert Nylon coupling into 90 degree fitting, install 90 degree fitting to PCV valve, trim ½” hose


Step 19: Insert ½” hose over coupling


Step 20: cut 1 pc of ½” hose to 20”


Step 21: Insert one end of ½” hose to front fitting on Air Oil Separator


Step 22 Insert 5/8” end of coupling into 5/8” hose


Step 23: Insert 5/8” tube over intake nipple


Step 24: trim ½” hose previously installed from step 21


Step 25: Insert ½” hose over ½” coupling


Step 26: Secure hoses with wire ties as needed


Step 27: Re-Install Air Intake hose to Throttle Body


Step 28: Re-Install Air Intake hose to Air Box


Step 29: Re-Install lines


Step 30: Tighten clamp on throttle body side


Step 31: Tighten clamp on Air Box side


Installation Complete

Draining of Air Oil Separator is needed; this will depend on driving conditions (i.e.) normal day to day driving check every 1,000 miles until a baseline is established. A good baseline is to drain the Air Oil Separator when it is about HALF full. This will vary with temperatures (cold winters vs. hot summers). For track usage Air Oil Separator will need to be drained after every outing.

There are several different methods to draining Air Oil Separator. The first and simplest method is to place a cup or MOROSO part # 65805 under drain elbow and open ball valve, once draining is complete close ball valve. The second method is to run a length of ½” hose from elbow to under carriage of vehicle and place drain pan under vehicle at this time open ball valve, when draining is complete close ball valve. This hose may also be permanently installed for future draining.

This guide applies to Mustang years: 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 and Submodels: Bullitt, GT