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A labour of love

Full rear wheel arch replacement

Full rear wheel arch replacement

Time for some bodywork, then. I’ve actually been plugging away at this for a couple of weeks now, alternating with the engine work to keep things interesting – really good to confront this and get things back on track at last. Here’s how I left things, that superficially OK-looking but actually totally rotten wheel arch is about to go.

And here’s the replacement. As well as offering the inner and outer wheel arches as separate panels, BMH thankfully also supply them both in this complete assembly, already correctly spot-welded together.

I took a first pass at the old metal with a cutting disc in the angle grinder and quickly got rid of most of it, before getting on with the actual hard work!

It was then probably a full day’s work with the spot weld drill and panel splitter to actually remove every last trace of the old panels and get it all cleaned back ready to accept the new assembly. Still massively infuriating that a lot of the welds I was drilling out were brand new ones I only made a few months back, but I tried not to think about that too much. You don’t often get a chance to see inside this part of the chassis rail, so it was really nice to see there is not a trace of rust inside it.

With that done, and everything inside doused in zinc primer, I next maneuvered the new assembly loosely into position, and then also offered up the new rear wing and clamped that into its correct, final position. With the wing in place I could then move the wheel arch around slightly to make sure it was completely aligned from every angle – hopefully taking the time to get this absolutely perfect at this stage will avoid the alignment nightmare I had on the other side. Having a complete assembly rather than 2 separate sections undoubtedly makes this easier as there is less margin for error.

You can see below that I’ve also pre-drilled the holes for the (many) plug welds which join the panel to the chassis rail flanges and to the back of the sill.

Here’s an internal view. I’ve committed to the position and removed the wing again at this point, and just started plug welding the boot floor corner onto the back of the arch (again). I spot-welded the flange which runs across the top of the arch onto the C-post/inner wing panels. It could have been plug welded as well, but I just bought a new spot welder and I’m going to use it wherever I can 🙂

Approximately one million plug welds later and it’s just about done. It’s a difficult piece to clamp in place in order to get good welding contact, so I used self-tapping roofing screws initially on every other hole to keep it held firmly in place. After welding up the rest of the holes I removed the screws and welded those ones up too. This is a technique I’ve never tried before, but it worked beautifully here.

I also appear to be trying a new technique here of getting rid of those bloody Heritage stickers by burning them off with MIG heat. Obviously it didn’t work.

All ground back and etch-primed, I offered the wing back up to check the fit again. Even with all the prep work I had put in to get it perfectly lined up I still have a bit of fettling to do around the arch lip, but it’s much, much better fitting than the other wing was initially.

Next up, I’ll paint all the internals just like I did on the other side and finally get the wing welded into place. I started on this corner of the car back in May last year, so I really can’t wait to move onto something else now.

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