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A labour of love

Rear axle refurbishment

With paintwork nearing completion, I’m planning ahead to getting the wheels back onto the car as quickly as possible, to enable moving it around the workshop again as needed, and the last big refurbishment job necessary for that to happen is on the rear axle.

As mentioned at some point before in a previous post, I purchased a replacement axle a long while back when I was first planning the V8 conversion. It had already been fitted with the correct 3.07:1 ratio crownwheel & pinion suitable for the V8 application, as well as a Quaife ATB LSD, and had covered very low miles. The exterior of the axle case had started to look a bit tatty, however, so was well in need of a repaint. It came complete with both brake assemblies, but I’ll be renewing them for good measure too.

In the picture below, you can see a small modification made to the former leaf spring locator bracket on the axle, which is required for the 5-link suspension conversion, I’ll cover that in more detail in my next post about that conversion.

The diff cover plate had a fair bit of surface rust and pitting, but not bad enough to justify replacing it (they’re a surprisingly costly part), so it was thoroughly wire brushed back before removing it from the axle for painting.

I stripped the brakes down completely and cleaned up the drums separately for painting. I decided not to bother disturbing the hubs and bearings in order to remove the backplates, as I knew they had been renewed relatively recently, so I cleaned the backplates up in-situ.

With the diff cover removed I got a good look at the Quaife LSD. I made sure everything was still totally clean inside, and then masked it all off carefully for painting.

Not the easiest of things to paint, but I came up with what I thought was the good idea of hanging the whole axle off of my engine crane. This arrangement actually worked rather well, and meant I was able to complete each coat of paint in a single pass (rather than doing half a coat and waiting for it to dry before rolling it over and doing the rest if it had been resting on the ground). In this picture, I’ve given it all a coat of Rustbuster Fe-123 Rust Converter to treat the last remnants of any surface rust prior to painting.

The drums were used but still had plenty of life left in them, so after a good cleanup also got the same rust converter treatment.

I failed to take any more in-progress shots, but the finished result is shown below. For paint, I opted to use Rustbuster EM121 epoxy mastic, which has exactly the right kind of thick and durable finish needed in vulnerable and exposed areas like the rear axle. I applied 3 coats and it came out really nicely, with a slightly textured finish that helps to disguise some of the surface pitting that remained in some areas. The diff cover was refitted using a new gasket and bolts, and the axle is now ready to meet the new rear suspension. I’m waiting for some brake parts, so I’ll build the brakes up later on once the axle is fitted.

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