17 replies to this topic

[aml1989]

Hi,

Car:
2000 Rover Mini Cooper 1275 MPI

I had drained my clutch master cylinder to fit a new slave, now I have put it back together I am unable to get any fluid moving.

Is there anything special I have to do when bleeding the clutch from starting from dry?

There's no change in fluid level in the reservoir when working the pedal, no visible leaks, no feel of fluid moving through the pedal and the bleed screw is dry.
Tried with a bleed kit and assistant working the pedal with no luck, and by myself with a long tube from the bleed screw to a foot pump for camp beds in an attempt to suck some fluid through.

Do I need a better system for a vacuum? Or is my master in need of repair...
What have other people done? Anything else to test for faults before dismantling?
Going to try disconnecting the pipe from the master when I get home, any other thoughts are welcome.

Thanks!
- Andy.

[nicklouse]

just fill it and bleed it.

 

why were you changing the slave?

[aml1989]

The plunger that moves the thrust bearing was seized (clutch permanently disengaged) so flywheel housing removed, clevis pins drilled out and put together again. The slave was pissing brake fluid out the seal when I took it off and corroded inside so repair kit didn't work.

Nothing comes out when I try to bleed it - all the fluid that went in is still in the master cylinder.
I'm worried in this time disassembled my master cylinder might have failed too...

[ukcooper]

you need two people.

fill the clutch tank

put ya spanner on the bleed nipple them put ya bleeding pipe on the nipple

one person slacking's the bleed nipple, second person pumps the clutch ( keep an eye on the tank to make sure it don't drain )
pump until bubbles go out of the pipe and lock the bleed nipple up tight all done.

summit eles wrong if that don't bleed it

[aml1989]

^^ something else wrong then!
Any tricks to identity what?

[Spider]

Often with new Master Cylinders, a Pressure Bleed in needed first up from dry (and new), like a Gunson's easy bleed.

 

I'm sure that the reason for this is that when assembled, they use a rubber grease and this seems to cover over the ports between the cylinder and the reservoir and with only gravity to get the fluid to move, it's often not enough to dislodge the rubber grease.

[panky]

I usually put a piece of tube into a jar with just enough clean brake fluid in to cover the end of the tube, fill the reservoir, crack open the bleed nipple and pump the pedal repeatedly until you hear the tell tail squish of fluid squirting into the jar. Helps if you have someone watching to top up.

[Boycie]

I usually put a piece of tube into a jar with just enough clean brake fluid in to cover the end of the tube, fill the reservoir, crack open the bleed nipple and pump the pedal repeatedly until you hear the tell tail squish of fluid squirting into the jar. Helps if you have someone watching to top up.

 

That can work quite well I find.  A short pipe from the bleed nipple into fresh fluid- that way when the pedal goes down, air is forced through the new fluid and bubbles to the surface- with the pedal coming up, it draws the fluid backwards through the system and hopefully starts to 'prime' the dry system. 

[minimans]

If the slave cylinder was that knackered did you change the hose? it may well be plugged after being moved around after fitting the slave, you didn't change the master so it should have been nice and wet inside and would not need priming like a new cylinder.

[aml1989]

Hose hasn't been changed, pipe has been changed.
Removing the pipe and rapidly pumping the clutch pedal shows fluid rising near the top of the master cylinder then falling back. Pressing and holding the clutch is unclear if the fluid rises and stays or immediately falls again... either way a few mm short of even the base of the pipe...
Time to get more tubing!

[Ethel]

Pull it through

 

You'll also want a little bit of rubber hose to connect it

[aml1989]

Clever... just a far superior method to my camp bed pump!
Will give that a go. If anyone needs to borrow my assistant to help with their car feel free!

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[gazza82]

... rapidly pumping the clutch pedal shows fluid rising near the top of the master cylinder then falling back ...

 

Doesn't sound right ..

[wile e coyote]

Pull it through

 

You'll also want a little bit of rubber hose to connect it

Or get cheap & suck it through - just use a long piece of fresh pipe and keep a close eye on what's coming through!!!

[aml1989]

I'd prefer to keep my lungs intact!

Would've been nice to know earlier my brother had a bleed kit you can hook up to a compressor - small leak at the banjo connection.
Explains why the standard methods weren't working if air was getting in here.