Rear Bulkhead Center

Description

The rear bulkhead center is the critical part which connects the right and left body center and where the fuel tank is mounted. Take extreme care to position the rear bulkhead center properly. Weld securely following the welder manufacturer's instructions to maintain the rigidity.






Replacement

1. Remove the related parts.
- Driver's and passenger's seats
- Fuel tank assembly

WARNING: Do not smoke while working near the fuel system. Keep open flame away from the fuel system. If necessary, remove the fuel tank and/or lines before welding nearby. Drain fuel into an approved container.

- Brake hose and pipes
- Side garnish
- Seat belt
- Engine assembly
- Electricals, and others
- Rear window

2. Pull out and straighten the damaged area.

NOTE: Make sure that the right and left center pillars are parallel to the rear window surface.

- The collision damage may extend to the rear bulkhead center may as well as the side panel outer and side sill. Check for the damaged sections carefully and pull them out with the frame straightener to reshape.
- Attach the car to the frame straightener by tightening the underbody clamps located at the jack-up points on the bottom of the side and sill and the side sill side flanges.




- To protect the car body from damage, place a piece of aluminum plate on each clamping section and tighten the clamps.
- Before pulling out the damaged sections, it might be necessary to heat the sections with an acetylene torch .
- After pulling, check the rear window rear side frame and rear side panel positions using the body dimensional drawings.

3. Remove the rear bulkhead center.
- Strike a punch in the center of the spot welds to the front floor, side sill, and rear frame.
- Drill the spot welds using a 10 mm (3/8") spot cutter.

NOTE: Take care not to drill through the front floor and inner side panel.

- Grind the MIG/fillet welds using a rotary cutter.

WARNING: To prevent eye injury, wear goggles or safety glasses whenever sanding, cutting or grinding.







- Remove the spot welds and fillet welds using a chisel.

4. Mold the related parts.
Correct the damaged section of the front floor and inner side panel with a hammer and dolly.

NOTE: Check the reshaped parts for cracks.

5. Set the new rear bulkhead center.
- Drill the 8-10 mm (5/16"-3/8") holes for MIG welding in the flanges mating with the front floor.
- Remove the undercoat from the welding section of the rear bulkhead center and expose the aluminum alloy base using a disc sander.

WARNING: To prevent eye injury, wear goggles or safety glasses whenever sanding, cutting or grinding.

- Remove the paint film from the welding section of the body using a disc sander and clean oil spots with a shop towel soaked with wax and grease remover.
- Remove the undercoat thoroughly from the underside of the front floor.
- Before setting the rear bulkhead center, clean the welding sections of the rear bulkhead center and body using a stainless steel wire brush.




- Clamp the front floor and inner panel with the vise-grips and pliers.

- Check the rear bulkhead center position using the body dimensional drawings .

6. Weld the clamped sections for temporary installation.

WARNING: To prevent eye injury and burns when welding, wear approved welding helmet, gloves and safety shoes.

Set the rear window and rear hatch, check for proper rear bulkhead installation.

NSX-T (open top):

NOTE: Use of a roof panel positioning jig is recommended.




- Install the roof panel positioning jig as shown.
- Check the roof rail and rear bulkhead center position.

7. Perform the main welding.

WARNING: To prevent eye injury and burns when welding, wear an approved welding helmet, gloves and safety shoes.







- Before welding, perform the trial welding following the welder manufacturer's instructions.
- Remove the oxide film from the welding sections using a stainless steel wire brush before welding.
- The applicable welding methods are MIG/plug welding or fillet welding.
- Check the welding sections for cracks

8. Finish the welding area.
- Roughly grind the welds with a disc grinder. Be sure to leave the finishing allowance this time.
- Finish grind the finishing allowance with a disc sander until it is smooth.

WARNING: To prevent eye injury, wear goggles or safety glasses whenever sanding, cutting or grinding.

- Take care not to grind the aluminum alloy base while roughly grinding the welds.
- Take care not to grind excessively.
- Do not press on the sanding tools excessively. If the disc face is clogged with the aluminum alloy particles, replace with a new disc.

9. Apply the sealer.
Apply sealer to the mating surfaces with the front floor and side inner panel.

10. Apply the paint.
See Paint Repair section.

WARNING:
- Ventilate when spraying paint. Most paint contains substances that are harmful if inhaled or swallowed. Read the paint label before opening paint container.
- Avoid contact with skin. Wear an approved respirator, gloves, eye protection and appropriate clothing when painting.
- Paint is flammable. Store in a safe place, and keep it away from sparks, flames or cigarettes.

11. Apply anti-rust agent.

12. Install the related parts.
Install in the reverse order of removal.

13. Check and clean.
Start the engine and check its condition.

NSX-T (open top):
- Set the roof panel, then secure the roof panel by turning the roof side lock handles.
- Make sure the roof side locks are locked securely.
- Check for water leaks.