Bleedin' brakes!

[terry t]

yes mine was new as well. but old stock. peal the dust cover of the master cylinder and check if it damp

[cunningplan]

don't know if this helps, but we had a Moggy Minor in the garage for the last few weeks, the guys in the workshop could not get any sort of brake, it just went down to the floor.
Last week it was a little slack for MOTs so I went and had a look.
I used my hand and pushed the pedal up and down very slowly, not much at first, then after a while (About 2/3 Min's) I had a little pressure at the bottom of the stoke. I got one of the so called mechanics to open one nipple until the pedal went all the way down. I done this on the rest of the brakes and after about 1/2 hour had good brakes.
One thing you have to check is the the piston is coming all the way back, you can check this by looking at the fluid, when you start to put the pedal down, there should be a little squirt of fluid (Or air) coming out of the little hole.

[ROD]

Terry I'll check this ,but havent put the dust cover on yet ,and it all got a bit wet when The eezi bleed pissed out everywhere! Strange how the 'pedal' is there when locking off the rear brakes tho'.
  Cunningplan . Minors /A35's can be an arse with the brakes. I may give that a go later!

[oldskoob]

still no joy mate?
if you want to try my master cylinder pop over tommorrow.it would rule out another  component .

[morrag]

I would have thought that this problem, having been covered under various other parallel threads on this site would have gone away by now, but, as I have pointed out previously in those threads, it ain't Rocket science, and with the leaks you admit to having you will never maintain an air free system, so start again. Separate front and rear hydraulic systems using blanks, redo all joints, fill the system, front or rear as selected, and crack the bleed nipples at slave cylinders, allowing them to drain by gravity until the piping is full. Once done, and with no leaks or of course "passing" cylinders! you MUST then get a brake once the bleeds are closed, even without final bleeding to eliminate all final air bubbles....you MUST!! really. If you don't, then your system is poorly installed and drawing air on cylinder return strokes, definitely. Once half of the divided system works, move to the other half and do the same. and eventually, put it all together,leaving any bias valves out, at least for now! they can be problematic, give it a try this way......please....Morrag

[Manky Monkey]

Going off at a bit of a tangent, is your brake pedal pushing the pushrod all the way into the master cylinder?

[Basket case]

2 thoughts;

If the fronts seem okay, can you close the bias valve and only 'work' on the rear brakes..?
(my nissan rears were a complete bugger to do, with such a long stretch from m/c to calipers)

If you are sure that there seems to be no air and its still not coming up to pressure, is the bore of the m/c big enough to power all the calipers/cylinders you are using ? (what front brakes have you)

Good luck...Bazza

[ROD]

OK guys .thanx for all the words of wisdom.A new day ,and a new set of ideas to try! Will be out there as soon as the shop opens to get more fluid!

[Daddy Bear]

ay up blokes i invested in one of them there vacuum brake bleeder it iz just the job got mine of evil bay realy easy to use hope the may help DB

[ROD]

Another waste of fluid! Took my 5/8" m/cyl off and replaced it with a  brand new 3/4" one borrowed from oldskoob.Bypassed the bias valve.Checked every joint for leaks. Bled out whole system . Still cant get a pedal.When I pump the pedal,I have brakes on all wheels,but a very spongy pedal.No more air coming out when I bleed them.I have 4 potcalipers on front ,Golfs on rear. Im absolutely out of ideas now,and just p****ed off bleeding the things!

 Hmmmm...now wheres that grinder..........................

[tbone]

Whats your phone number Rod? pm me.

[ROD]

pm sent...........

[Basket case]

Another waste of fluid! Took my 5/8" m/cyl off and replaced it with a  brand new 3/4" one borrowed from oldskoob.Bypassed the bias valve.Checked every joint for leaks. Bled out whole system . Still cant get a pedal.When I pump the pedal,I have brakes on all wheels,but a very spongy pedal.No more air coming out when I bleed them.I have 4 potcalipers on front ,Golfs on rear. Im absolutely out of ideas now,and just p****ed off bleeding the things!

 Hmmmm...now wheres that grinder..........................

If you've got 2x 4pots on the front, then the m/c might not be moving enough fluid for the whole set-up. My mate Pirate had problems with just one 4pot (changed from a single pot) and got frustrated to hell, bleeding bleeding bleeding, and no pressure....He borrowed a modern bigger bore jap m/c off me, designed for 4/6 pots and it works great. (bugger still has it  ) Is there an even bigger bore m/c you can try
Good luck...Bazza

[ROD]

I see where youre coming from and yeah there are larger bore cyls,but I doubt whether it is that. I just cant get any pressure on the brakes unless I pump them a lot.When I had the bias valve fitted ,if I closed it,I had perfect pedal on the fronts. So I would come to the conclusion a) there isnt enuf 'push' in the smaller bore m/cyl OR b),as TB and others have suggested, air in the rear lines/calipers. BUT Ive bled the s**t out of them!Going out fer anuver try now..................

[ROD]

Right this is where Im at....Removed and pluged off rear brake circuit at the T piece. Result = instant rock hard pedal for front brakes. Step two...removed/ plugged off front brake circuit at T piece.Replaced pipe to rear brakes. Bled out rear brakes again ,tapping the calipers to remove any trapped air.Result = as before ,no pedal!