Heeeeeeeeelp !!!!

[Matt No VAT]

I am now in a rather fierce mood because of my brakes.

So far I've done £57 in AP600 racing fluid and I still have no brakes whatsoever.

I have flushed out all the old fluid, had my uncle operate the pedal the old fashioned manual way down/close valve/up/open valve/down etc etc.

Then I buy/try the one man brake bleeding kit, (a rubber hose with a one way valve) Think ...as much use as a chocolate fireguard.

Then I borrow a pressure bleeding kit, fill the bottle with AP600, attach to a tyre that is at 20psi (they recommend 22) and pop/whoosh/splatter..... one exploded cap and I have a £20 puddle of fluid both over and underneath the car! I also tried the tyre at 12psi - similar but a more delayed approach... it waits for you to get to the farthest wheel before it shoots its bolt. Anything less that 6psi and it wont pump the fluid thru the system.

I should buy shares in AP not only will the share price rise due to (my) increased demand but I should get the fluid cheaper as I'm a stockholder.

So after I've come to the conclusion that there must be an air lock in the master cylinder, as the fluid is pumped thru the system but theres nothing at the pedal, if the pedal is pumped furiously then there is a small amount of pressure for approx 10 seconds...then it fades away.................like my patience :~(

Can anyone out there offer inspiration? Recommend a bleed kit that "ACTUALLY WORKS" I seem to recall someone bleeding thiers thru from the bleed nipples...GMC was that you? If so where can I buy this piece of kit? Alternatively can anyone pass me a number of an Anger Management Course?

So far the only advice I've had is "drive 40 miles to collect the trailer, drive the car to my mates garage, then trailer it home again, drive the trailer back to the garage, then drive home" - a round trip of 240 miles and an entire day lost............for a set of brakes????????

:mad: :confused: :mad:

[David May]

Can't be an airlock if you've had that much pressure behind it!
Are you sure the master cylinder piston returns fully when the pedal is released? If the travel is too short, it won't open to the reservoir and nothing will ever flow.

Dave M

[Matt No VAT]

If I depress the pedal with the cap off the reservoir I get a nice fountain of brake fluid !!

The new things that have been introduced into the braking system are the Aeroquip braided hoses, and the 164 calipers at the front.

I'm 99% sure that the M/C piston is functioning correctly as A) It was fine before the brake conversion, B) with any of the valves open it seems capable of pumping fluid around the system.

Theres no leaks from any of the unions - I've checked every single one of them...several times!

[Stratos]

Matt,

I have one of those pressure bleeders, but I always start at about 15psi rather than as high as 20psi. I found at 20psi it would leak at the cap, as you have mentioned.

Similarly, mine won't work when the pressure gets down.

Having said all the above, I have had good success with mine, and use it all the time to bleed my brakes.


I take it from your comments, that the master cylinder hasn't been dismantled at all, and the only things that have been removed/changed are the 164 calipers, and the new braided hoses?

Do you have a single master cylinder, or a twin master cylinder setup?

Does the master cylinder have an integral reservoir or a remote reservoir?

[GMC]

Matt.
What I used to bleed the brakes when on my own is a simple syringe (I do not know what cc is it as the writing has disappeared off it, but it measures 120 x20 mm), I put a short plastic pipe onto the end connect to the bleed nipple and away you go. !
The Alfa 164 calipers, fitted the correct way round, bleed nipple to the highest point, ? and the pipe out of the master cylinder, not higher that the unit itself ? sound like you still have air in the system ?

Gerard.

[rutthenut]

I've never tried any of these bleeding kits (dodgy pun!) as I recall a friend having problems with one many years ago - which resulted in a lot of corrosive brake fluid all around the engine bay of his car.

I stick to the old-fashioned method of pressing the brake pedal and having the tube from the bleed nipple going into a jam jar of fluid. Even manage to get a firm brake pedal when working on my own. I also make use of a broom wedged between the seat back and the brake pedal to hold it in the down position to avoid drawing back any fluid into the system. Very low tech, eh?

Matt, have you managed to get any fluid coming out of the brake calipers when pressing on the master cylinder? I'll assume that you have done. Have you continued to wind out the bleed nipples further to get some 'real' fluid flow at that end?, which may just get some more air out of the system. If you only allow a small 'dribble' then it might not be clearing properly.

Other than that, I've no bleeding clue :eek:

[chris.richard]

Could you have a small crack in a pipe where you can't see it - like in the tunnel? Eventually enough fluid'll come out to draw your attention to it....

[David May]

If it squirts loads back into the reservoir when you press the pedal, it still sounds like a master-cylider problem to me. Once the piston has passed the intake port there's no way it should let fluid back again.
Maybe a quick squirt for the first bit of travel is OK.

Dave M

[Matt No VAT]

Due to my having to fit a new front door on my house today before the renderers arrive tomorrow, having to attend a funeral Saturday and my birthday falls on Sunday, I will be resolving the brake issue Sunday..... I cant think of a better way to spend my birthday!!

Just as well someones bought my old Integrale race car engine so I should have a few £££'s in my pocket!! I may invest some of that in more AP600 ;~)

I have not looked at the car since loosing my patience with it all - I should have calmed down enough to re-visit it by Sunday.

I am off out now to purchase the biggest syringe I can find and follow GMC's method as that has proven success.

I have plenty of advaice from everyone on here (many thanks guys) fingers crossed Sunday will prove to be more successful.

Regards

[chris.richard]

Good luck, we look forward to hearing the result. Fingers crossed!

[Mel Lewis]

By the way your discribing it i'm afraid to say your master cylinder is knackered:(

[Matt No VAT]

Well I finally have brakes!! Hoooorah

I tried GMC's technique of pumping the fluid up into the system from the bleed valves, I don't know where the air lock was exactly (I was unable to see what was going on at the reservior)but this method obviously shifted it first go and I got some pressure under the pedal after one visit to each valve, after that I reverted back to the manual pedal operation method with a one way valve kit and this flushed the remaining bubbles of air out of the system, so now I have fully operational brakes :~)

Many thanks again to all those who gave thier advice - it's very much appreciated.

Now the car can come down off the axle stands and finally start the interior refit. :~)

[chris.richard]

I'm now going through the buggeration that Matt described above, only with less success. I've used pressure bleeding, pedal pumping, both of the aforementioned, I've syringed up from the calipers, and the pedal is only slightly firmer than it was. With the engine on, there's no resistance . Any offers what I try next? :confused:
Pissed off and desperate. :mad:

[chris.richard]

I've now put 2.5L of fluid up it, down it and all over the floor. Still a soft pedal. Am I looking at a new mastercylinder?

[chris.richard]

Seem to have got somewhere. I took all the calipers off so that I could bleed them with the bleed screw uppermost. I think the 164 rears are probably OK anyway, but the fronts have the bleed point well below the hose attachment. Got air out of both fronts and the pedal is much firmer, though not as much as I would expect. Enough to get the car on & off a trailer for painting anyway.

[mudhut]

May not be the cause but...

Triumph Dolomite 1500 hydraulic clutches were always a pig to bleed. You would think it simple enough and the Herald was very similar in nearly all respects (same master cyl except for the reservoir angle, same slave except for the union thread) and never a problem. The only significant difference was the hydraulic hose on the Dolomite. On a Herald it was the usual thin metal type as use for brake lines. On the Dolomite it was a much larger bore semi-rigid transparent plastic pipe.

What this means to me is that any trapped air in the pipe is not flushed through by the flow, as much of the trapped air does not completely obstruct the pipe the fluid flowing round it. The large bore tube just makes this worse. What does the trick is a really rapid flow, maybe with the bleed nipple out and a temporary bleed fitting put in. This also causes enough turbulence in the slave cylinder to dislodge air too. Can't see why you should not catch and immediately reuse the fluid if it is all clean and refurbed, just for the purposes of air removal. Can flush it all through once bled completely. Are you using long lengths of large(ish) bore flexible hose?

Helps to have bleed nipple at highest point as you have already found.

All this reminds me of my dad right now - drip up, urinary catheter and syringe driver. Could easily see the liquid passing right by various bubbles in the drip tube.

I suspect you have already considered all the above Chris... :D

[guy mayers]

How come the bleed nipples are below the inlet pipe Chris? Are the callipers on the wrong sides?
Guy

[chris.richard]

A good question, and one that had me running to the cardisc to check. Yes they're on the correct side, but on the 164 they are mounted more horizontally on the top of the disc, while on the Hawk they're vertical at the back of the disc.

[David May]

I assume you've tried loosening the inlet pipes as a makeshift bleed point while somebody else pumps up pressure?

[chris.richard]

Got a bit closer tonight. Took off the reservoir from the M/C, removed the 3 pipes and replaced with blanking plugs. Rock solid pedal, so M/C is OK. Replaced pipes one at a time. Rear - hard pedal. Offside front - slightly soft, re-bled and now hard pedal. Nearside front - soft as a marshmallow. re-bled twice, still soft. At least I know where the problem is now.

If you remove a caliper, remember not to pressure bleed it unless you've put a G clamp or somesuch in to stop the piston from being expelled. Just a tip I picked up somewhere..... :rolleyes:

[strat6v]

sounding like one step forward, two steps back!

[CorseChris]

Nothing much to add by way of help, but I must have used about 3l of fluid to bleed the Alfa recently when I had to remove & strip the ABS unit. Kept thinking it was nearly there, then it would make an obscene gurgling noise and no pedal again.

Had a problem bleeding the clutch on the Corse. The slave piston was hard against the bottom of the bore and was stopping any air getting past (Mini type slave). Poor design really. The Fiat item has a nice bypass drilling and the end of the piston is tapered so it can't block flow. I loosened the slave connection and bled it till it reached the slave, tightened it back up and it was no bother after that.

Brakes were OK using the common method of undo bleed, press to bottom, do up bleed, lift pedal, repeat, but took 3 good sessions to get right, separated by quite a long period of time (months).