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I have 4 nos 'baked bean tin' clutch and brake master cylinders, the push rods are different lengths, which should I use on my '68 Mini?

Should end up with 70mm with the pushrod fitted.

Does anyone have the dimensions of the ST master cylinder push rod length as I have the cylinder and need to sort out the push rod.

Thanks

WNX700H wrote:Does anyone have the dimensions of the ST master cylinder push rod length as I have the cylinder and need to sort out the push rod.

Thanks

It should be the same as in the picture [70mm]. As I understand it the length of the m/cyl. pushrod dictates where the brake pedal pad sits at rest. Any shorter then the pedal will be in the wrong position and you may not get full stroke on the piston, any longer then the bottom of the clevis will touch the inside of the crossmember box and might stop the cylinder piston from returning fully.
The 'cranked higher' brake pedal of the 'S' models was built into the pedal itself, but the clevis pin position is the still the same.

You may find this useful:

http://www.cbsonline.co.uk/product/5|16 ... vis_CLEVIS

You would need to saw off the existing clevis and thread the remaining shaft 5/16" UNF. When the holes wear oval, unscrew it and just put another one on...

You could set the pushrod to any length you want to within reason.

Don't forget to use a lock-nut!

The best part, I think, is that you do not need to fit/splay open a split pin, and we all know how difficult that can be sometimes

ianh1968 wrote:..The best part, I think, is that you do not need to fit/splay open a split pin, and we all know how difficult that can be sometimes

R clips are good. Once you've tried them you can never go back



Tim

St master cylinder info for WNX





If you cross reference the part number its the same one as an innocenti one

Hope it might help

R clips are the nuts! Long nose pliers and R clip, job done.

AndyB72 wrote:R clips are the nuts! Long nose pliers and R clip, job done.

Agreed, but I am always worried that the clip will rotate 90 degrees and get "automatically"
pushed back out by the action of releasing the pedal...


You will have seen how close the clevis is to the bottom of the access hole where the
push-rods live!

Funny I was only chatting to another member of this forum yesterdayand I think it was Keith Calver mentioned in a mag about how he lost his brakes after the clip let the pin loose.I believe this is known as a focusing moment

The R clips aren't very big. Turned 90° they wouldn't project beyond the outline of the clevis. There's a remote possibility that they'd touch something, but if that was happening a split pin would be doing it too, which wouldn't be too good for your pedal feel. The picture below shows the old and the new on my Traveller. The old one seems to have collected a couple of interesting modifications in its 50 odd years.



On my first Mini as a teenager I had terrible trouble getting the clutch to clear. It sort of worked but I couldn't get enough throw from the hydraulics. I tried all sorts of interesting bodges, but eventually discovered that the clevis pin had fallen out and the pedal was just pushing against the base of the clevis. Gee it was good after I fitted a new pin!

Tim

R clips are great, standard fitment in the later Aust built cars, but the are now R clips and R clips. I bought some a little while ago that were a little bigger than the originals. After a couple of clutch operations the pin must have spun and the pedal was stuck about half way down, would still go to the floor, just not come up until the pin spun a little further.

I do recall wrestling with a a car fitted with a split pin years ago, damn ugly that was!