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A labour of love

Brake servo rebuild and installation

Brake servo rebuild and installation

A nice clean, and moderately simple, job for today’s update. You might have seen in my previous post about zinc nickel plating that I had already restored the case of my brake servo, so this post will cover the disassembly, reassembly and refitting in more detail.

My servo is a genuine original Lockheed unit, though not the original one to my car (I think it came off the donor GT I bought during my last restoration years back). It worked OK as far as I can remember, but it had obviously become rusty at some point in the past and been crudely repainted silver all over, so it now needed a makeover before it was fit to go into my pristine engine bay again. Originally the main servo housing would have been plated, whilst the piston housing would have been plated black (from what I can see in original period photographs), so that is how I intended to restore it.

Having taken it all to pieces, I wire brushed the piston housing to bring it back to bare metal and remove any loose rust. I then masked it off, etch primed it, and gave it a couple of coats of satin black paint.

I had withdrawn the piston assembly itself very carefully, and took the photo below mostly so I had an accurate record of how it needed to be reassembled when I fitted the new seal kit. The rebuild kit for these servos is widely available from all the usual suppliers and includes all of the service parts you could require. As I mentioned, it had previously worked just fine, but I changed everything for the new parts for good measure whilst I had it apart.

Here’s another quick detail shot of the disassembled unit after some light wire brushing, but prior to the electrolytic cleaning and plating processes.

And after the plating process was completed, looking much smarter.

Fully reassembled and ready to be fitted, a nice satisfying job to have completed. Sure, I could have bought a brand new no-name servo off the shelf and bolted it straight in, but it’s a nice feeling to have brought another bit of original specification equipment back to this condition, and it wasn’t a difficult job.

Here it is back in position on the car being plumbed into the braking system. I had also had the original mounting brackets sandblasted and powder coated, so overall the whole unit is now looking a lot more presentable.

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