I am working on an early 1958 XK150 OTS with round brake pads on the rear.
Are the replacement round pads held onto the metal backing plates with anything besides the small alignment screws? Any adhesive?
Should the pad removal (alignment) pins travel freely in the bores of each hydraulic cylinder or is there a spring in the cylinder for each pin? Travel for the pins seems restricted.
Any help would be greatly appreciated!
Thanks,
Dave Winne
Liverpool, NY
david.winne@verizon.net

 

You'd be far better off if you junked those calipers and installed a set of the square pad calipers fitted to the later cars where the spares situation is a whole lot better. These early round pad calipers are a pain to service, because every time you want to replace the pads the whole cylinder assembly has to be removed. Like the later cylinders, yours will have a pad withdrawal mechanism, probably at the bottom of the cylinder with a very limited amount of movement ( a few thou), but to cater for wear there has to be a mechanism that allows the piston to gradually move outwards yet still allow the withdrawal mechanism to work. So there is a form of clutch which on these would seem to be the retractor pin and bush assembly. If you look on the SNG Barratt website you'll see the two different assemblies. There seem to be no part available now for the early rear circular pad brakes.