Brake master cylinder servo removal

[Sparepart]

I'm rebuilding the Exmo after 17 years under a tarp. I'm re fitting the brake servo and master cylinder, the ones from the donor Sierra. I'd forgotten how close to the exhaust manifold it all gets. I stripped the master cylinder to find a sorry state of gunge and corrosion. The bore is so-so but the rubbers and springs are shot. I could buy a repair kit, however I suspect it would not last long. Getting a whole new master cylinder (Lucas/Girling Part No. 74066315) is prooving elusive. So I am going to try fitting a Ford KA master cylinder without a servo. Searching our archives here there are plenty of mentions of this having been done, however no specific information with part numbers and instructions. Does anyone here have such information that they are willing/able to share ?...... I have bought a cheap used "KA master cylinder" on eBay, (waiting for delivery), and will soon start trying to make it fit.

[Foz]

It's a few years since I did this on my 2B and I have been thinking of doing the same on the cobra but, unfortunately, I can't remember all the details myself  .

What I can remember is :-

The master cylinder was from a Mk1 KA. It was a black tubular steel thing with 3 outlets and (I think) 19mm bore.  Looking around these don't seem so common now although there are lots of the cast aluminium type which may well do the job, but I don't know what bore size they are.

As far as I can remember, I just drilled 2 new holes through the pedal box & bulkhead for the fixing bolts and simply bolted it on, centred on the original servo mounting position.

I lashed up a piece of M8 threaded bar with a couple of nuts as a push rod and adjusted the nuts to get the correct length/pedal position.  I then made a new push rod from a length of 10mm round bar based on these dimensions.

Hope this helps - if I remember anything else I'll let you know.

Steve

[Sparepart]

Thanks for that. The £13 KA master cylinder arrived. It's for a MK2 KA. It looks like its not a repairable item, no circlip holding the piston in, also it features one of those tiny trapped ball bearings that is probably some form of pressure relief. The diameter of the ring on the mounting surface is quite large. On the plus side the two output ports would be on the side away from the exhaust manifold. The diameter of the bore is not obvious. Googling away for more info it appears that on the KA the two outlets are used for diagonally opposed brakes, and there are two possible bores 20 and 21 mm. So on the face of it this might not be the best candidate. I am going to continue with trying to fit it, however am busy web surfing for other possibilities, preferable with 19 mm bore.