norton 93 Posted April 6 (edited) anyone tell me which servo this is? It does work and the car stops fine except there is a very hard pedal with almost no movement, i was wondering if the wrong type fitted maybe or with a too long connecting rod? ( the pedal does sink a bit when the engine is started with foot on brake....so it does work, but i think it could be better) . Any ideas? Edited April 9 by norton Quote Share this post Link to post Share on other sites
sheffieldcortinacentre 641 Posted April 6 That's the girling one fitted to all UK built cortinas upto late 81. Quote Share this post Link to post Share on other sites
norton 93 Posted April 7 13 hours ago, sheffieldcortinacentre said: That's the girling one fitted to all UK built cortinas upto late 81. hmm, thanks...might have been swapped then as this is a German built car. i feel there is something not right but I cant single out what it may be. it stops fine, but ive never felt such a hard pedal. if anyone has one for sale and could bring to the Yat, im in the market for a replacement, just in case there is a problem with mine. Which is most likely? servo, master cylinder or callipers? all clues welcome. (partly blocked vaccuum pipe perhaps? Quote Share this post Link to post Share on other sites
sheffieldcortinacentre 641 Posted April 7 Sounds like it's working right to me apart from hard pedal. Difficulty to say without being hands on. Quote Share this post Link to post Share on other sites
norton 93 Posted April 7 2 hours ago, sheffieldcortinacentre said: Sounds like it's working right to me apart from hard pedal. Difficulty to say without being hands on. Been thinking about it, i must check the callipers, i wonder if they could be partly seized with just enough clearance to run without binding. I recall when I bought it, it had brand new pads fitted and wouldnt roll correctly until they'd worn down a bit. That might explain so little pedal travel needed until they are full on (i imagine) Quote Share this post Link to post Share on other sites
norton 93 Posted April 8 i had a look the callipers are actually very good, and so are the pads. i suppose there are more people complaining of the opposite pedal problem so i guess i'll leave it be . i do think the servo is potentially weak, i'll have a look at the vacuum pipework tomorrow. I adjusted the handbrake, it just about will hold the car on my steep drive so i'll leave that be too. I hardly think it has anything to do with servo... Quote Share this post Link to post Share on other sites
norton 93 Posted April 8 if anyone has a good girling servo to sell and are going to The Yat, give me a shout. i'd take a master cylinder too just to have. Quote Share this post Link to post Share on other sites
TimB 70 Posted April 8 The seals in the brake callipers are static in the housing and have a squarish profile. When the piston moves outward to press the pads the seal distorts and then when the pressure is released it should return to rest shape and allow the piston to return letting the pads sit in the off position with a gap between them and the disc so the discs turn freely. This also gives the disc brake self adjusting feature. Listening to the brakes were binding before the new pads wore down a bit suggests the calliper seals have gone hard and less flexible. This can give good brake operation but not letting the pistons retract to the rest, free play position. There is no other way of checking this other than taking the callipers off and stripping them and changing the seals. It's a common fault, especially on old classics that may have had periods of low mileage. They also clog up with brake dust from the pad wear, the dust seals leaking letting in water and road dirt etc. If you jack the car up, remove wheels and pads you should be able to carefully push the pistons right back into the housing (G clamp) to see if they retract fully. Before doing this make sure the brake fluid in the reservoir has enough space to rise as you push the pistons, if not syphon some out. (Don't want to squirt or leak it over the paintwork). Something to try, servo does sound to be working. Good luck Quote Share this post Link to post Share on other sites
norton 93 Posted April 8 (edited) 3 hours ago, TimB said: as i said, the callipers are fine. Edited April 8 by norton Quote Share this post Link to post Share on other sites
TimB 70 Posted April 9 Ok sorry, hopefully they are. I was only highlighting them because in the past I've messed about trying to get callipers that look good externally to retract and the only solution was strip and reseal. If new pads are tight and make the disc bind it suggests piston sticking problem, and also give odd pedal feel. But I'll accept your assessment. Good luck. Quote Share this post Link to post Share on other sites
norton 93 Posted April 9 no the pads were brand new when i bought it 6 years ago. that's not the problem. Quote Share this post Link to post Share on other sites
norton 93 Posted April 9 Ive got another problem now... i think the front brakes are OK... having gone out and done a few emergency stops.... but now the back brakes seem to be partly seized on, so that's the next job. Mighr be connected to adjusting the handbrake cable or maybe where i slammed the brakes on hard, it's caused something to stick, presumably the cylinders. Quote Share this post Link to post Share on other sites
norton 93 Posted April 9 2 hours ago, norton said: Ive got another problem now... i think the front brakes are OK... having gone out and done a few emergency stops.... but now the back brakes seem to be partly seized on, so that's the next job. Mighr be connected to adjusting the handbrake cable or maybe where i slammed the brakes on hard, it's caused something to stick, presumably the cylinders. ive edited the title.... with the aid of a haammer and a block of wood, i got one drum off, it was very tight. Neither wheel was turning freely. i released the bleed nipple for second and the brakes came off with a clunk.... both sides, i hadnt touched the other side... does this mean i need new wheel cylinders or is there some other liekly reason? there is a slight weep of brake fluid at the cylinder, very slight. Quote Share this post Link to post Share on other sites
norton 93 Posted April 9 (edited) It’s more or less the same problem as I had when I brought the car to the Yat two years ago, then I got new shoes for it and had no problem since, thought I’d solved it… a couple of weeks prevopious to that, I had had the problem occur for the first time, and it was under heavy braking , just as this time. It’s as if the fluid gets pumped through under pressure and can’t get back again…. So would that be wheels cylinders or maybe the equalizing valve or even the master cylinder. ( if the latter, could it relate to the hard pedal…) Edited April 9 by norton Quote Share this post Link to post Share on other sites
sheffieldcortinacentre 641 Posted April 9 Collapsed brake hose acting like a non return valve , is a common fault on vehicles the see in frequent use. Quote Share this post Link to post Share on other sites
