A. Crack 20mm or Less In Length (Structural Epoxy)

A. Crack 20mm or less in length (structural epoxy):

The following procedure is to be followed to fill the cavity above the left rear mounting point for the rear axle carrier with structural epoxy. This structural epoxy will both reinforce the affected area, as well as help prevent future damage to it.

NOTE:
The following procedure is for an E46 coupe, but can be used on all variants knowing that there may be some minor deviations. In addition, the following procedure should be performed with the vehicle in a location where it can stay for 24 hours following the repair, to allow the epoxy to cure.

1. Remove the floor trim from the luggage compartment

2. Perform all applicable safety precautions when working with seam sealer and structural epoxy.





3. This illustration identifies the area inside the trunk where the following procedure will take place.





4. Identify the following 3 points which will be used in this repair. This area is located above the left rear mounting point for the rear axle carrier. Holes (2) and (3) will be filled with urethane seam sealer to create a barrier and thus a sealed cavity. Hole (1) will be filled with 2 complete cartridges of structural epoxy. These 3 holes will be referenced by number throughout this procedure.





5. Hole (1) is present and is sealed with a body plug.

Hole (2) is not present and must be drilled. It should be drilled halfway between Hole (1) and the similar hole on the right side of the luggage compartment. A 10mm stepped drill bit should be used.

Hole (3) is present but is covered by the anti-vibration liner. Locate the hole using the dimensions provided and expose the hole using suitable tools.





6. Use a length of tape or a body plug to seal the hole (1) from the underside of the vehicle if it is present on the vehicle.

This hole is located immediately to the right side of the left rear mount for the rear axle support (2).





7. Prepare to install the seam sealer into Holes 2 and 3 from Step 4 by placing a 250mm (10") length of 3/8" clear flexible tubing (locally sourced) onto the nozzle of an open cartridge.





8. Looking at the bottom of the seam sealer cartridge, measure and record the distance to the plunger (A). This is necessary to ensure the correct amount of seam sealer has been injected since it's a blind operation.





9. Place a tape line on the tube 120mm (4-3/4") from the open end. Insert the tube (1) into Hole 2 up to the tape line. Directly below Hole 2 is an existing hole (2) of similar diameter. The plastic tube must go through this hole and reach the bottom of the cavity. This illustration shows a cutaway view to illustrate the triangular shape (3) of the cavity which is to be filled.

10. Inject the seam sealer while slowly pulling back on the plastic tube to create a vertical barrier in the cavity. The amount of material that must be injected is the equivalent of 12mm of travel of the cartridge plunger.

11. Once the seam sealer has been installed, measure the position of the plunger again to ensure that it has traveled 12mm from the position previously recorded in Step 8.

12. Measure and record the position of the plunger similar to Step 8. The area under Hole 3 will be filled next and is much smaller than Hole 2. Therefore the plunger in the seam sealer cartridge only needs to be depressed by 2mm.

13. Insert the plastic tube into Hole 3 (identified in Step 4) and fill the cavity with seam sealer.

14. Once the seam sealer has been installed, measure the position of the plunger again to ensure that it has traveled 2mm.

15. Wait at least 10 minutes for the seam sealer to set before continuing with the next step, structural epoxy installation.





16. Remove the fastening nut and sealing plug from the structural epoxy cartridge. Next, install the mixing nozzle (1) onto the cartridge pack and secure it with the fastening nut (2), both of which are supplied with the cartridge pack.





17. Install the included extension tube (1) over the end of the mixing tube (2).

18. Due to the high viscosity of the two part structural epoxy, it must be warmed in order to flow out of the cartridge pack properly, and into the void it is intended to fill. Two cartridge packs are required for this repair. Place both cartridges packs under hot running water or in a large pail of hot water for 15-20 minutes to heat the contents thoroughly.

19. ct the recommended pneumatic applicator to a shop air supply. A pneumatic applicator is recommended as a manual applicator can make it difficult to fully fill the necessary cavity. The recommended applicator is the same one previously recommended for use in SI B54 04 08.





20. Feed the flexible extension tube into Hole (1). About 10mm below
this hole is another hole which this tube must be fed through.

21. Inject the entire contents into the cavity. The red line on the side of the applicator will display how much has been injected. If the material begins to flow too slowly, warm the cartridge pack with an electric heat gun (set to low heat) to improve the flow.

NOTE:
Take appropriate safety precautions when using a heat gun, and be sure not to heat the cartridge too aggressively as the plastic cartridge container could melt.

22. Remove the flexible tube and repeat steps 19 20 with a second, already warmed cartridge pack.

23. Remove any protruding structural epoxy while it's still flexible and seal the holes with body plugs.

24. Reassemble the vehicle and allow the epoxy to cure for a minimum of 24 hours.

NOTE:
The vehicle must not be moved until the structural epoxy is fully cured.