43 replies to this topic

[cal844]

What order are you bleeding them?

Have you tried loosening each union and pump the pedal until fluid comes out? You'd be best to do this at the FAMwtf valve

[Norris73]

Using the Normal order

 

Passenger Rear

Drivers Rear

Passenger Front

Drivers Front

 

Have tried loosening unions at master cylinder one a time, pressing the pedal, then chocking it down with a piece of wood while tightening unions. Fluid came out of both unions.

[cal844]

Using the Normal order

Passenger Rear
Drivers Rear
Passenger Front
Drivers Front

Have tried loosening unions at master cylinder one a time, pressing the pedal, then chocking it down with a piece of wood while tightening unions. Fluid came out of both unions.

Good man ? you might need to loosen the unions either side of the FAMwtf valve to get the air out

[Norris73]

Still no joy with this, 4th day on this now. Have tried loosening the unions around the FAM valve, no change. I have even now out of desperation replaced the master cylinder - just as well the old part was dated 1997. New master cylinder is in and everything bled through, still as before a poor sinking brake pedal. Im beginning to think Minispares has sold a duff FAM7821 valve, however the valve does provide fluid out of both lower ports, I get fluid at all wheel cylinders and the valve doesn’t leak like the old one did.

 

Super frustrating as the brakes were perfect before the so called 'classic specialist' garage thought they new best and mis adjusted my rear brakes causing the fluid to boil and I have no doubt wreck the old FAM7821 valve.

 

I have left the pedal chocked with a piece of wood and the master cylinder cap just sitting on top of the cylinder - out of hope that some air may magically escape overnight and all will be well again...

Edited by Norris73, 30 December 2018 - 04:16 PM.

[Magneto]

On my 1980 there was a weird brake bleed procedure buried in the back of the Haynes manual. As I could not get my brakes bled properly either, I followed it - and it worked!

 

From the book: open the bleed screw furthest from the master cylinder, push the pedal down smoothly (don't stomp it) hold for three seconds, close bleeder then let up slowly. wait 15 sec and do it again. I did this about three times then did the other side. Worked a treat! Bled the fronts in the normal way - pump, pump, pump, open bleeder with pedal down, close bleeder - repeat. Take's two people of course.

 

Worth a try....

 

My car had been converted to front discs but I doubt this matters.

Edited by Magneto, 30 December 2018 - 04:35 PM.

[imack]

If you have access to four hose clamps I'd clamp all the hoses (assuming they're not braided) and check pedal feel and creep. At least you've then eliminated problems with air or adjustment at the wheels.
Next I'd remove the pipes from the master cylinder and install bleed nipples, carefully bleed and check for a solid pedal feel to confirm master is ok.
If ok refit pipes to master cylinder and fit bleed nipples into outlets of FAM valve, carefully bleed and check pedal feel.

[Homersimpson]

Do you have an ezi bleed? If not get one as they are worth their weight in gold.  I have used them on all my restorations and they always work first time if the system is right.

 

If you have no leaks but the pedal sinks to the floor then you must still have air in the system, the suggestion about clamping each brake hose in turn is a good one.

[Norris73]

Have never had any success with Eezibleed on the Clubman, works no porblems on my Mini 1000 with cooper s discs, but refuses to bleed properly on the Clubman with drums all round.

 

My plan now is to go to Minispares in the morning and buy yet another FAM7821 valve (I am suspect of it, as it was the only part to change and brakes were no good straight after fitment, the box had clearly been opened at some point, and what looked like oil was soaked into the brown paper that the valve was wrapped in). Will return if no good, as I suspect.

 

Magneto: Thanks for the tip regards bleeding, will try this coupled with another new valve and report back.

[cal844]

Get the valve replaced, it's been fitted previously. Then what I'd do is plumb it up to the master cylinder lines and pump the pedal, if fluid comes out you know you have no air in it. Then fully install the valve and bleed normally.

If you still don't have a pedal I'd now clamp all four flex lines testing the pedal before you add the next clamp.

If it improves on one corner that is the corner to concentrate on. If no improvement with all 4 clamped I'd look at deleting the FAM valve and using an inertia valve kit (Retroman on here does them... Retro minis website)

[Norris73]

New valve is on. Was working alone today so bled the unions around the master cylinder and FAM valve, wedging the brake pedal in place with a piece of wood. Air was definitely evident escaping from the unions, which can only be a good sign.

 

I had a go at bleeding the rear wheels with the same method of wedging the brake pedal down, opening the bled valve and closing while still wedged down. Fluid is definitely coming through on the rears, but it never seems to make it all the way along the pipe into my jar of brake fluid, it seems to recede back into the pipe and head back towards the bled screw. Even after repeating this procedure a few times the fluid still never makes it to the jar, like I remember it doing when bleeding the system in the past.

 

Perhaps I will have more luck tomorrow when I have an assistant to operate the brake pedal.

[Ethel]

The Fam7821 will at least isolate the rear circuit if it fails, the rear subby valve won't.

 

It looks to be plumbed correctly if the photo with the yellow band master is as it is now. The bottom outlet of the master is the larger bore, pushing more fluid but with less pressure - what you want for the rear brakes, which connect to the inboard side of the FAM valve (outlet is offset from the inlet, so slightly further inboard.

 

The downside of having a valve that isolates leaks  is that it can be a bugger to bleed. The easiest method I've found is to avoid pressurising the system by sucking the fluid through instead, all you need is a syringe and length of hose. It also has the advantage that you only need to be at the drum/disc end to bleed, but be sure to keep the reservoir topped up. 

 

The first thing that happens when you press the pedal is the master cylinder pistons go past the inlet ports from the reservoir, isolating it. Afraid there wouldn't be any air escaping back to the master if you chocked the pedal down. You'd have to loosen the unions to let it out of vertical Master anyway as they're higher than the reservoir ports.

 

Bubbles going back up your bleed hose is normal as air is lighter than brake fluid. Close the bleed screw or have a loop in the hose that's higher.

[Norris73]

I have attached a picture as it is plumbed now. Brand new yellow tag master cylinder and pipe work, the front and rear pipes were incorrectly plumbed previously (inherited car this way). Has now been corrected, with lower port feeding the rear circuit (right hand side as you look at it of the FAM valve).

 

 

 

 

Attached Files

•  IMG_20181230_155040.jpg   83.15K   0 downloads

[Norris73]

Still trying to get my brakes back I have a helper today and we have been trying to bleed the brakes since 9:30! We can get the pedal about 1" from the floor if we are lucky. The rear brakes expel plenty of air for the first 3 or 4 cycles then as mentioned the fluid seems to slow to a trickle and return back to the bleed valve. The fronts expel plenty of air and plenty of pressure the fluid keeps on coming and the air stops. I think the rear is an issue, perhaps why the garage reversed the master cylinder lines all those years ago, to make it possible to bleed the system - Im actually tempted at this rate to do this myself.

 

I have been round the system and pulled all drums, and can confirm no leaks!

 

Its so frustrating, not alot phases me - Have changed engines, clutches, clutch hydraulics, rebuilt brakes etc - but this is really starting to get to me now! Help!!

[Steve8274]

What about trying gravity bleeding. You can do all wheels at same time if you wanted.
Simply attach hose to the bleed nipples into a jar, slacken the bleed nipple and go and have a brew. Come back and the fluid should be dripping out. Obviously keep an eye on fluid level to ensure it doesn’t go too low.
Also, maybe try putting tie wraps around the bleed nipple hose. If the hose is too big, then air can be drawn back in as you are trying to bleed.
By doing the above, this helped me to get a good pedal on my brand new system.
Hope you get it sorted soon

[Norris73]

Another couple of hours spent on this, this morning. Still no joy!! We have a really weak pedal about 1" from floor. My thinking is this resistance is from the front circuit, as when I have had the fronts circuit disconnected in the past the pedal remained half way when braking force felt (rear circuit), the front circuit when bled always seemed to add the final 1/4 or so of pedal travel to make the brakes apply about 1/4 of the way into the pedals total travel.

 

Something I have noticed is when an assistant pumps the pedal I can hear air/ bubbling in and around the bulkhead valve area - not massive but audiable of each stroke and release. I have been around all the unions with kitchen towel and can find no leaks. Having said that the metal pipe work on the bottom of the valve is all the original stuff, but again can see no leaks! Is it possible to have a leak so small air is drawn in but fluid does not escape?? Should you hear air in the valve or is this a sign of a leak. I have fluid coming out of the master cylinder and the bottom unions of the valves with no air bubbles. You then go back to it a few minutes later and air is present again. Rear circuit seems worse.

 

I have a friend who has kindly offered to help tommorow for 5 hours but after that am on my own. 7th day today trying to get the brakes back! This car was a working going concern until the 4th Dec when a 'classic specialist' massively overtighten the rear brake adjusters, which over heated the rear brakes, boiled the brake fluid and cooked the FAM7821 valve causing it too leak!

 

Is there anyone in the North Essex area who could perhaps help on Friday if I have no luck tommorow. WIll cover travel costs. PM me!

 

Thanks,

 

Olie

Edited by Norris73, 02 January 2019 - 10:33 AM.