Repairing Chassis Subframe Mount Thread On Front Longitudinal Member

Information 

The cut-out diagrams of the thread repairs are examples and are designed to show the installation dimensions of the threaded insert. They do not always show the exact component on which the threaded insert is installed.

Overview of standard thread on front longitudinal member

Threaded bushing in chassis mounting

1. Drill out thread.
   1. 1.1 Fully drill out old threading using drill bit supplied in set -B-  .

   Drill

   Information 

   • The M12 repair bush must be installed recessed. The tool from the Porsche special tool  > 9395 - Time-Sert thread repair set must always be used for milling in the relevant shoulder. The commercially available Time-Sert milling tool must not be used for this! 
2. Mill shoulder.

   Use an electronically controlled power drill set to a speed of approx. 250 ¹ /_Min for milling in.

   1. 2.1 M12:
      1. 2.1.1 Use a spot facer -C-  to mill in the bore hole to dimension -X-  .

      Spot facer

      Sink the shoulder -X-  until the next level on the countersink is touching the outer sheet metal edge. > Test and adjustment value 12 mm 

3. Cut thread.
   1. 3.1 M12:
      1. 3.1.1 Cut thread to dimension -Y-  in the chassis bush using the cutting tool. > Test and adjustment value 40 mm 

         Thread cutting tool

      2. 3.1.2 Clean the threading on the chassis bush.
4. Position threaded bushing on screw-in tool.
   1. 4.1 Clean threads on bushing and on screw-in tool.
   2. 4.2 Oil the screw-in tool -E-  .
   3. 4.3 Screw threaded bushing -A-  onto the screw-in tool -E-  by hand.

   Threaded bushing on screw-in tool

5. Screw in threaded bushing.
   1. 5.1 Screw in threaded bushing -A-  fully using the screw-in tool -E-  .

   Screw-in tool

   Information 

   • While pressing in the base thread, a noticeably larger amount of force on the screw-in tool is required to form the internal thread. Pressing is finished when the screw-in tool can be turned further more easily. 
6. Pressed threaded bushing.
   1. 6.1 Form and press the threaded bushing -A-  by turning further with the screw-in tool -E-  in the base thread.

   Pressed threaded bushing

7. Unscrew and remove screw-in tool -E-  from the threaded bushing -A-  .

Screw-in tool