help needed (clutch Hydraulic problems)

[jamestoledo]

Have a problem with my car 76 toledo. Over the winter i sent my car to the garage to get the exhaust welded up and whilst it was there i asked if they could replace the slave cylinder which was leaking as it was too cold and to be honest i didn't feel like being under the car (lazy i know). My dad picked up the car after the work was done but he said the clutch pedal was soft and the gears crunched when shifting, he then took it back and they said the master cylinder was now leaking so they sourced a new one from rimmers and fit that. when i picked it up they said the master cylinder didn't fit the threads of the clutch pipe so made an adapter to fit on it. all was well for a few days until i felt the pedal becoming softer and softer whilst driving along for no more than 2 miles. at one point it went straight to the floor and had no pressure behind it which was bad as i was at a set of traffic lights so had to push the car to the side of the road. i looked into the master cylinder reservoir as saw lots of bubbles coming up and a line of them coming up the clear pipe. even pumping the clutch didn't get any pressure back so had to wait for the whole system to cool before the bubbles got out of it and could even select a gear. i re bled the system when i got back and the pedal felt good but again after a mile or so the pedal softened and gears were hard to select. i took it back to the garage and asked them to check it and just told me i bled it wrong. they re bled it with a machine so was properly done and once again pedal felt good but after a few miles was soft and could see bubbles in the clutch pipe. both cylinders are new (although i think the master is wrong because its the same shape as the one off a herald/spitfire) but was told that was the one they sent from rimmers. i don't know what else to try or what could be wrong with it. i don't really want to take it back to the garage (which was classic car restorer garage) because I've sent over £300 fixing this problem and they honestly made the car worse. any suggestions?

[Toledo Man]

Air is getting into the system somewhere and you can't eliminate the new parts from the equation as there are some poor quality parts out there. You will need to check the entire system for leaks and you may have to reseal the master and slave cylinders if they're leaking. Don't leave the clutch pipe out as there may be a problem with that as well.

[Edin Dundee]

Where are you James?
Perhaps an experienced forum member can help out.

[jamestoledo]

Thankyou for the advice Toledoman ill check them when I'm next home, and I'm in peterborough but don't really know anyone yet who can help I'm new to the whole forum thing.

[WDRVM]

I agree with Toledo Man. Though personally my first port of call would be to check the unions and bleed nipples are tight(often overlooked and a simple fix if it is the cause. Make sure all the pipework is sound; corrosion of the metal pipe, splits, cracks or crazing of the clear pipe. Then the slave cylinder, as you said there are a stream of bubbles coming up through the pipe when you depress the clutch pedal(is that right?). It may well be that dirt/grit has fouled the seal and is causing the leak or that the union isn't sealed properly, given the system has been taken apart recently and it wasn't like it before. Then the master cylinder.
I don't know how much experience you have with brake bleeding but use an Easi-bleed if possible (or a jar, with a hole poked through it's lid and a length of clear pipe attached with one end pushed through the hole in the lid so the open end is at the bottom of the jar and some brake fluid in the jar, enough to cover the end of the clear pipe) as it saves air re-entry and it also becomes a one man job.
Some say you can take the whole lot off the car and bleed it with the help of gravity, although I have never tried this method personally.
Best of luck.

[jamestoledo]

Thanks for your answers guys!! I checked both cylinders and they were fine, however when i checked the knew master cylinder i noticed that the threads where the clutch hose union joined was really badly damaged by the garage since they bought the wrong cylinder and forced the union into the wrong sized threads. i put some PTFE tape round the union and worked really well for a while, got me all the way down to cornwall which was about 370 with the clutch working beautifully. However now the clutch seems to be sucking in air again as i saw bubble in the pipe and the biting point is lower and sometimes harder to downshift. I'm wondering if i can add some sort of sealant round the top of the cylinder where it meets the union to see if that will be a fix or will i have to removed the union again and add some more tape round and re-attach?

[Pippin]

Silly question, but why don't you go back to the garage and politely suggest they put the problem right at their expense, seeing as they caused it!

[jamestoledo]

i went back a few times and each time they re-bled it and said its fine. I've had too many bad experiences with them and they did this work over christmas so i doubt they would touch it again without charging, and I'm in cornwall now so its a bit difficult to do as well. I've paid them too much for too little now i don't want to give them anymore.

[Pippin]

I appreciate your dilemma. Have you considered reporting the garage to Trading Standards? It might not help you, but I feel they should be taken to task for fitting the wrong part, badly, and not putting it right despite several opportunities to do so, particularly on a roadgoing vehicle.

[Jon Tilson]

What you need to do is repair the thread in the master cylinder. This is possibly best done by working out what the thread is and going up to the next size for which there is an adaptor. Moss have quite a few thread adaptors which are like a big nut with a female end to match your pipe and a male end to go into the master.

If the union on the pipe is damaged you can either get a new pipe for about 20 quid or cut the flare off the pipe and change the union.

You are wasting your time with a PTFE plumbing repair. It wont last as hydraulic pressure is much too high as you have found.

Jonners