Although politically incorrect, my 53 FHC is fitted with a single master cylinder. Probably because when the double m/cyl gave up, a replacement was not readily available and a previous owner, at the time, decided to reverse to the single version, just like the factory eventually did later with the inception of the XK140. I have a brand new master cylinder, a new single line fluid reservoir, and I also have the 2 new short brake lines to connect the reservoir to the master cylinder, one fitted with a female fitting to fit the reservoir (that fits well) and one fitted with a male fitting to accept the original banjo (which I have) on top of the master cylinder. So far, so good! Unfortunately, the hole at the top of the master cylinder is too big to take the original size banjo bolt. The way I see it, I have 2 possible solutions :
find an adapter either male/male or male/female to the size of the hole in the M/cyl on one side and the normal size on the other end (I can make another pipe with male fitting if necessary)
find an adapter to fit both the M/cyl and the original union and banjo bolt, on which an original size male fitting will connect.
The new master cylinder I have came with the car when I purchased it and was supplied by Moss Motors. But it may not have been intended for an XK, some other cars, such as the MG TC I believe, shared the same unit.
Sadly, I am not familiar with English threads (I’m a metric person) and I don’t know the size or type of thread at the top of the M/cyl. But all the other fittings are original to the car and fit properly.
Can anybody shed some light on this. Any suggestion or tip will be greatly appreciated. Thanks to all. XKs forever! Bernard
The MGTC master cylinder is nothing like it. The MGTD/TF was a smaller 7/8" bore.
There is a major difference between the single system cars and the tandem system cars, which is the mounting bracket welded to the chassis. The bolt spacing is wider on the tandem. This began with chassis number 679622, so lets first be sure you have the right information about which your car is supposed to have. What is your chassis number?
Sounds like you need the bushing as pictured in Rob’s post…perhaps sold separately by the usual suspects? This bushing has straight, or parallel, threads as the use of a copper gasket indicates.
Hi Dick,
Yes, I have considered going back to the twin master cylinder, but I’m trying to avoid it if I can, since I already have (almost) all the parts for the single one. Thanks for responding.
Regards
Bernard
Hi Rob and thank you for responding. I know I should have the tandem brake master cylinder. However, as I explained, someone before me made the change over. My chassis number is S 681137, built in April 1953.
It seems to me that if I could find the proper adapter for the top of the master cylinder I have, I can make everything else work fine. As a matter of curiosity, I will crawl under the car hopefully tonight to see what kind of setup is there. As you indicate, I should not have the mounting bracket, so I will get back to you on this as soon as I find out.
Regards
Bernard
Hello Bernard, you may also wish to determine if the master cylinder you propose to use is suitable for the application. Mismatched hydraulic parts could lead to unexpected results, e.g. brake pedal reaching bottom before brakes lock up.
Hello Lee and thank you for your interest and participation to my current nightmare! I agree with you that all I need is some kind of adaptor or as you suggest, the proper top of master cylinder. The usual suspects are not very helpful with this matter. This being said I just found out that XKs sells an adaptor (picture enclosed) that just might be the ticket. To be continued…
Regards
Bernard
The mounting bracket is in my picture on the right and you can see my chassis number stamped on it. The two holes in that bracket have to match the two holes in the master cylinder.
That appears to be the part…about 14 bucks…better call them to make sure, and, get the correct copper washer, which is further down the same page(or so it would appear).
Update. After crawling under the car with a flashlight, it appears, as it should be, that the car was originally fitted with a tandem brake master cylinder. As I have stated in my first post, before my time, someone replaced the original m/cyl with a single line type. In order to do so, they just drilled an extra hole in the bracket welded to the frame, as well as a hole in the outside long mounting plate (to which the spring is attached). Furthermore the rod connecting the pedal to the m/cyl has been made longer by welding a piece of rod in the middle of it, retaining the possibility of adjustment. Even though a fairly nice job was done, I am not completely satisfied with it, but my priority is to put the car back on the road in this lifetime and since I already have nearly all the parts needed for the conversion to a single master cylinder, I’ll go that route. As for the initial problem of the master cylinder which has a hole too big to take the original size banjo bolt, I am ordering a new m/cyl top from XK unlimited, hoping that this will solve the problem.
I’d like to warmly thank all of you who responded to my post and offered advice and tips on this matter.
Regards
Bernard
