Clutch slave cylinder bleed screw

[croc7]

From the "For What Its Worth" department; When I replaced the clutch slave cylinder I found the bleed nipple to have a longer grip length than the one it replaced. The result was a sloppy fit where the spring attachment tab fit against the body of the cylinder casting and less tension on the clutch lever return spring. A couple of thick washers fixed the problem. I know that some may use a substitute spring with less tension or don't use one at all, but is my understanding that a strong return spring will keep the throw out bearing from constant contact with the clutch diaphragm.

[AndyPen]

A nice to know, especially the idea of using washers if that happens. Aren't the correct bleed nipples easily available though?

[croc7]

A nice to know, especially the idea of using washers if that happens. Aren't the correct bleed nipples easily available though?

Probably. Before installing, I tried fitting the old nipple into the new valve but didn't feel the the threads matched and wasn't sure about the contact surfaces mating well enough to seal. The cylinder was already installed/bled-didn't want to go through all of the monkey motion a second time, so whipped off the nipple and installed the washers without spilling a drop of fluid.

[rogerotto66s]

I am having the same problem.
I was thinking of using washers as well but am opting to purchase a new bleed nipple.
Mini Spares 3H2428 £1.20

[rogerotto66s]

I am stuck and need your input!
My current task is to bleed the clutch.

Engine is in. Rebuilt master/slave cylinders in. All hoses connected. Bonnet/hood is on.

I can not gain access to the slave cylinder bleed screw!
Obviously space is quite tight with everything connected.
The carbs, heat shield and dogbone severely restrict spanner/wrench movement.

Here is what I see :

FAADBD3E-92CA-46B1-AFFB-F641680230CB.jpeg

Suggestions would be appreciated.
Only option I can see is to remove hoses (heater, servo) and possibly brake servo.



Another forum topic recommended modifying the bleed screw access which looks great!
Here is the pic from that topic. Wish I had seen this earlier.

B5C84CC2-CB10-4A91-8092-7329B0937B8D.png

[Oneball]

Can you unbolt the slave? Then you can get to the bleed and once it’s done bolt it back in place.

[Peter Laidler]

Unbolting the slave cyl is a bastard. Read article in 'Mini how to' section. The best idea is that shown above by Doc Mabo and designed by Dearg of this forum I say

[rogerotto66s]

Problem solved!
Thanks for your input.

I removed the fresh air hose and the brake servo hose.
This gave me enough room to access the bleed screw (back of my hand is bloody)!

905532D7-F59E-4C6E-A885-F6BCF7A799E1.jpeg

Then using an offset 7/16” ratchet wrench/spanner I was able to access the bleed screw by staying to the outside (left)
of the Dogbone.

AD45F641-C330-4C9D-A7F4-2C7F54F7BE95.jpeg

Then I was able to attach an adapter and hose to the bleed screw. No need to remove the slave cylinder at all.

534FA04F-4E92-4E98-AB5F-6F92A66A77F6.jpeg

Hopefully this is the hard portion of the job.
Next up is the “bleed”!

[AndyPen]

Thanks for the heads up on this one. I'd totally forgotten that mod, and its a darned good one!!

[Peter Laidler]

When doing that 'Dearg' mod to my car, I did a couple more for Clever Trevor and Mini pick-up man who are both well on the way to finishing their resto's. Cheapest, simplest, best and most worthwhile mod ever designed for a Mini

[rogerotto66s]

Well I thought I was done bleeding the clutch (used Eezi Bleed System) ..... BUT .... I noticed a few drops of brake fluid on the garage floor the next morning.

So .... I removed the brake servo, disconnect brake lines and a few hoses to gain access to the slave cylinder.

I have isolated the problem to the hose feeding the slave cylinder.
The bleed screw seems to be OK.

I have tightened the slave onto the hose as much as I can.
Here is a picture showing a towel for another leak check.

D6F3EF80-D392-43B6-BB28-DFFEF605E7D2.jpeg

What is most likely cause for a leak at this location and what options might I have should the leak continue?
This is a new hose!

As you know the hose is a bugger. Th slave is screwed onto the hose and not the reverse.
Is there a hose available that has rotating ends allowing the hose to screwed onto the slave.

[Dearg1275]

You should screw the hose to the slave and then fit the other end of the hose to the bulkhead bracket. This way you have no torsion in the hose and you can get the hose nice and tight on the slave.

D

[rogerotto66s]

You should screw the hose to the slave and then fit the other end of the hose to the bulkhead bracket. This way you have no torsion in the hose and you can get the hose nice and tight on the slave.

I should have thought of this!

If the leak continues what is the easiest/safest way to remove/replace the hose now that I have already bled the clutch?

[Dearg1275]

Screw a plastic bag under the master cylinder filler cap then just take it all apart. You will obviously have to bleed it all again but at least your master cylinder will stay primed and you won’t loose too much fluid. Just stand by with lots of soapy hot water to wash any spills away.

Good luck.

D

[Spider]

Check the Spot Facing on the Slave Cylinder where the Hose Screws in for a scratch or marking, like wise the copper sealing washer. It doesn't take much at all to stop them sealing. If you find a blemish in the Slave Cylinder body, unless you have a means to machine that back flat and square to the thread, it's possibly best left and a soft washer, like a fibre type fitted in place of the copper one. Unlike the brakes, the clutch doesn't (or shouldn't !) build up big pressures.

Unbolting the slave cyl is a bastard. Read article in 'Mini how to' section. The best idea is that shown above by Doc Mabo and designed by Dearg of this forum I say

Since reading that in your article Peter, i have made up some spacers and had them plated. When I find the need to be bolting on (or back on) one of my Slaves, I fit one. Certainly resolves that ! It was THE only bolt on the whole car that I HAD to use the 3/8" Drive set on, being the only thing that would fit. I'm not adverse to sockets but for most work, I prefer the feel of spanners. Now, I can spanner this one off too.

In return of the favour, this is another modification I've been fitting for many years now, sorry it's a poor angle (it's a snippet from another photo);-



I always found it quite annoying to get a hose on to the bleed nipple and of course, if the engine had been run recently, one needed to wait some time for the exhaust manifold to cool down before getting one's hand in there. Also, as Roger found, you need an odd ball spanner to get to the nipple. This remote bleeder gets around both of those issues.

[Peter Laidler]

While we're here Roger, the same method applies to fitting the caliper hoses too. Screw and tighten into the calipers first THEN fix into sub frame without twisting. It will form its own natural curve.

I seem to recall that the brake and clutch hose retaining nuts are secured by externally toothed star washers. My teaching (being taught and teaching) was to always use INTERNALLY toothed star washers. If you're making your own stainless nuts, they're 5/8"i/d 26tpi UNF

Interesting thread

[rogerotto66s]

Making progress ... although slowly.

Just purchased a 15/16”12-point spanner to remove the hose retaining nut. The plate which holds the dogbone does not allow the use of a socket to spin the nut. I did not want to remove the plate!

437AA6B5-E54F-4E27-BD87-DB8A2C807387.jpeg

So ... nut is off, hose is off. Easy with the proper tools!

Today I am off to purchase a copper washer and a fiber washer to attach the hose to the slave cylinder.
Then I will re-bleed and test for leaks again.

[Fanfaniracing]

I would not use a Fiber washer, as in my opinion the Copper is better with the pressure in the system...
Never ever had an issue using copper

[Peter Laidler]

I agree with FanFan. Copper is best. It will compress to suit but fibre is still just that....., fibre.

[davidmuir]

Peter, what is the size of the union and bleed screw? Been looking on net but so much "stuff' comes up!!