Mad Scientist left me a gem.
As Rich told the story his parents somehow got an Introductory Unit built for a customer. He said his father complained about the brakes while it was under warranty. He said that his folks were given a complete replacement unit, but kept using the original. It sat on a shelf until about 15 years ago. He had no need for Continental valve covers as he had swapped engines and they didn't fit. If memory serves me he gave the car disc brakes and scrapped the inoperative Treadle Vac, but kept the one on the shelf until he felt I needed it more. It looked a little natty, but it was all there. It showed up about the time I was finishing the Ruxton and I was under pressure and forgot about the package. The first major mechanical overhaul I did on a Mark II had a leaking Bendix that had eaten away the zinc surface for the seal rendering it useless. I contributed the near flawless rod from Mad's unit, and kept all the other parts, disassembled, in a box.
The vacuum canister was dull zinc and the Bendix had a nice die cast zinc finish listed in the Authenticity Manual, which strangely, doesn't list a color for the lid. All I've ever seen was black, but it turns out they were not painted black, the steel covers were plated with a thick copper coating. The coating had weathered to black, a common transition. I glass beaded all three covers I had and found that two were heavily pitted. I was astonished to find the patina melt away revealing a bright copper coating. Glass bead doesn't remove metal, but it eats the oxide's surface. I built two T-Vs, but was told to keep the best parts for myself. It turned out all of the ones that show were from Mad's T-V.
With the help of HarmonClassicBrakes.com I was able to obtain two terrific kits which included a stainless steel replacement rod for under $400 delivered. It come with hose clamps for the internal vacuum line, but I'd advise not using them as they don't allow for full travel of the stainless steel rod, necessary to tip the fill switch every time you take your foot off the brakes. If it doesn't travel far enough the tip switch will never open.
There are a lot of screws. If you do this be prepared to chase every thread with a bottoming tap. Take lots of pictures. It comes with few written instructions, but the exploded view of the parts tells all. It was all worthwhile. I was about to zinc plate the screw in cap I had left, not knowing there was another lurking nearby. It was the one that came off of Mad's! It's in pretty great shape! I think this T-V was the Holy Grail of MarkIIdom. It even has a double struck F on the nose piece that only the Mark IIs were stamped with.
If you have an early car fitted with a '54-'55 sleeve valve unit you should be aware that they work great when new, but the slide valve wears with use. They don't fail in a normal way. As the slide valve gap opened it creates a vacuum leak that gradually makes your car revert to normal brakes without you noticing until you need them. The replacement poppet type for '56-'57 became the direct replacement for the sleeve-valve as they made no more. I would imagine that there would be very few left by now. I found that out when I searched for a rebuilder 20 years ago. No one at that time did the sleeve machining, that I could find. Also I'm finding few people lubricate their Treadle-Vacs. I discovered that parking backed into a normal, sloped, garage floor makes any moisture laden brake fluid that eventually separates out to cause the fluid to pool at the nose of the vacuum chamber when the drain hole is at the back. Pulling in nose first actually helps the water drip out.
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