| Repairing
Your Bulkhead Part 2 |
A Note on Repair Panels: There is a lot of variation in the quality of repair panels available. None are perfect. There is some variation in the original firewalls but we have yet to find panels that are made exactly to the original dimensions. We used the panels supplied by roversnorth and while imperfect, are probably the best available. You will notice they have the ribs in the lower footwell area as the originals did. Visually we wanted to retain this feature and these panels are the only ones that have it. The panels differered in several areas from the originals so a significant amount of trimming was required to get them to line up correctly and look the way the originals did but the results were worth the time spent during repeated test fitting.
Footwell Repair: Toe Board and Kick Panel:
(click for larger images)
This is typical lower bulkhead corrosion requiring the replacement of the toe board and kick panel. It certainly looks ugly but a quality repair here is not difficult.
This is how the footwells are originally constructed on a mid SIIA firewall. The towboard and upper footwell are actually one piece with a stiffening panel spot welded in place making the entire area more rigid where the pedal boxes attach. (picture taken with the firewal inverted) The repair panels available that do have the original style pressings come in two peices (upper and lower) and the stiffening panel has been reduced in size so that it fits entirely on the upper section. Since the repair panels consist of two individual, overlapping pieces there will be a seam in the middle where they meet and the smaller stiffening panel reduces the orveral rigidity of the assembly. You will notice that some high dollar shops claim a perfect original repair but gloss over this difference. You can easily make a more original repair. Read on.
Disassembly is the most important part of repairing a firewall corectly. In general try to be as conservative as possible so that the original costruction can be replicated when reassembling. The footwell panels are secured with spotwelds to the door posts and doghouse of the firewall. Drill out these spotwelds in order to remove the old rusty panels. Removing the footwells in this wat will ensure that the completed repair will appear as the original did. Above you can see the original spot welds have been drilled out seperating the panels without cutting.
Take note of construction details during disassembly. Here you can see a small weld securing the upper footwell panel to the kick panel. While this may seem anal to replicate a detail nobody is likely to notice, the goal here is to make an original looking repair, not just fool someone who doesn't know what they are looking at.
Here you can see the doorpost with the footwell carefully removed. Mark the holes that were spot welds to distinguish them from the holes used for riveting the door seal to the seal lip. During reassembly this will allow you to put the spot welds where they belong. Also take note of the two small tack welds in the right side of the first photo. These will need to be ground away to remove the kick panel. In the second photo you will see another weld which secures the flange on the upper footwell to the kick panel and a stiffening web. This will also need to be ground away to remove the kick panel. There are also spot welds lower on the same flange. These will need to be drilled out. On some firewalls there is a sneaky spot weld hiding at the top of this flange above the stiffening web and behind the door post. It can be hard to spot but drilling it is important to easily removing the kick panel.
Once the kick panel has been removed the new panel can be test fitted. You can see that correct removal of the old panel makes reassembly much easier. The stiffening web refered to in the last set of pictures is visible here at the right side of the photo. Since the panels are lightly galvanized, mark the panel where it will be welded on reassembly and grind the coating away to ensure a strong weld
Here you can see the new panel spot welded in place. Since you drilled out the original spotwelds, simply use a rosette weld to fill the holes made during the removal process. This will put the new welds in exactly the same place the originals were for a nice looking repair. In the second photo you can see the reverse side of the panel where it has been welded. The white dots show where the galvanizing has burnt off in the heat affected area behind the rosette weld. In the first photo you can also see where the toe board was carefully cut away from the upper section.
Here you can see the stiffening panel we removed from another damaged firewall. This panel is important to making the footwall look correct and also maintain its original rigidity.
The original upper panel has been attached to the replacement toe board. The weld was then ground flush so that the panels appear as though they are formed from one peice of steel as they originally would have been. When we do the other side we will detail this process a little closer.
On the inside of the footwell the stiffening panel has been welded into the repaired footwell. The completed assembly is constructed exactly the way the factory did it except for the now invisible seam between the upper panel and the toe board.
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