Messer 2 Posted August 31, 2015 Luckily I was just pulling up outside a friends house, I pressed the brakes and pedal went straight to the ground and would not pump. It's a 66 mk1 gt. I pulled the hand brake and that worked and slowed me down and the brakes were perfectly fine after this. I'm presuming that it's a fault with the auto adjusters some how? Has anyone converted to a dual circuit brake system and if so what is the master cylinder to use? Quote Share this post Link to post Share on other sites
Lotuscops 73 Posted August 31, 2015 Luckily I was just pulling up outside a friends house, I pressed the brakes and pedal went straight to the ground and would not pump. It's a 66 mk1 gt. I pulled the hand brake and that worked and slowed me down and the brakes were perfectly fine after this. I'm presuming that it's a fault with the auto adjusters some how? Has anyone converted to a dual circuit brake system and if so what is the master cylinder to use? Don't want to smash it again Tony! I doubt it's the adjusters as the front calipers would have come on - have you a servo fitted? Quote Share this post Link to post Share on other sites
Messer 2 Posted August 31, 2015 No servo. That's the thing if the pressure is all used pushing the rear cylinders out then the fronts wouldn't work either in a single circuit set up Quote Share this post Link to post Share on other sites
henry320 1 Posted August 31, 2015 No servo. That's the thing if the pressure is all used pushing the rear cylinders out then the fronts wouldn't work either in a single circuit set up if it were the adjusters, the handbrake wouldn't have worked. sounds like master cylinder to me, tony. Quote Share this post Link to post Share on other sites
Lotuscops 73 Posted August 31, 2015 if it were the adjusters, the handbrake wouldn't have worked. sounds like master cylinder to me, tony. Me too. :thumbup: Quote Share this post Link to post Share on other sites
the-ford-cortina.com 225 Posted September 1, 2015 (edited) Me too. :thumbup: and me - sounds like the seals have failed Unless its lost all its fluid from a leak - have you checked brake fluid level ? Edited September 1, 2015 by the-ford-cortina.com Quote Share this post Link to post Share on other sites
Messer 2 Posted September 1, 2015 That's the thing. They have been fine ever since.. just did it once and then after I pulled the had brake it's worked fine ever since Quote Share this post Link to post Share on other sites
Tigdlo 24 Posted September 1, 2015 At the front end of the master cylinder, there is a valve which closes when the brake pedal is operated, and prevents fluid being pumped back into the reservoir. Possibly, some dirt had stopped this from closing, or maybe it is worn out. Quote Share this post Link to post Share on other sites
myle087 2 Posted September 1, 2015 Had you been doing a lot of hard braking before you pulled up or had a brake been binding on any wheel,both these circumstances could cause fluid to boil resulting in loss of pedal which would return to normal when fluid cooled down. Quote Share this post Link to post Share on other sites
Messer 2 Posted September 1, 2015 It's a brand new cylinder as well. Everything is brand new or refurbished.. nothing has been binding or driven hard etc.. Quote Share this post Link to post Share on other sites
myle087 2 Posted September 1, 2015 A lot of play in a front wheel bearing can cause piston in caliper to be pushed back and you would have to pump same as after fitting pads to regain pedal. Quote Share this post Link to post Share on other sites
Lotuscops 73 Posted September 1, 2015 The trouble is now you are just waiting for a repeat - think I'd replace everything in sight if it were me.... Quote Share this post Link to post Share on other sites
the-ford-cortina.com 225 Posted September 1, 2015 It's a brand new cylinder as well. Everything is brand new or refurbished.. nothing has been binding or driven hard etc.. newly manufactured or new old stock? - seals can easily fail in new old stock parts . Not going as far as Keith's plan , might be an idea to bleed off all the brake fluid out of the system and replace with new. Quote Share this post Link to post Share on other sites
Messer 2 Posted September 1, 2015 It's a new club cylinder. I just wonder why it was fixed as soon as I pulled the hand brake? Quote Share this post Link to post Share on other sites
DJKhmor 0 Posted September 16, 2015 exactly the same thing happened to my 1200 Mk1 too... out of the garage no probs, first red light perfect brakes, next red light no brakes at all... zero brake fluid loss and no leaks anywhere... was able to pump the pressure up after a few minutes... pulled back to the garage and left it there... this was 2 years ago today the pressure is still there and it still hasn't lost a drop of brake fluid, the chamber is full... but I don't dare to drive it anymore... this has never happened to any of my other cars... nice to hear I'm not the only one this happened to, but doesn't make me feel more confident :( Quote Share this post Link to post Share on other sites