Clutch Slave Cylinder bleeding

[Sandgrounder]

Finally got round to replacing Clutch Master cylinder on my S3 this morning.
Bit of a b*gger to get at the nuts in the footwell, and would have been a lot easier if I had another pair of hands on the other end stopping the bolts spinning, but got there in the end. In fact, I had to install the replacement twice, as after I got it in there the first time, I noted that the rod was about an inch shorter than the original.
So, out it came (having just siliconed it in) and I ended up having to remove the push rod off the original and put it on the new one. Hopefully that will work.

Then came the scary bit. Jacked up the offside of the car and wedged two axle stands under it (unfortunately noticed a small hole near corner of outrigger!) then tentatively slipped under the car. I always get stressed that it will collapse on me, resulting in a slow painful death).
The bleed nipple on slave is at the bottom?? I had to remove the nipple to get the pipe off (new pipe getting made up this week as union on Master is rounded). Virtually no clearance to release pipe union, but managed it eventually.

So, I presume the bleed nipple at bottom is acceptable, as it has been like that for years. Presume Slave was installed that way to give access to the nipple, as I can't imagine it being accessible at the top?

I have purchased a Gunson Eezi bleed as I have read on here that they are a must when bleeding the clutch.

[Spanish S2]

Hi Graham, my clutch slave cylinder was changed recently as the old one was leaking and the bleed nipple was
on the bottom of the new one.

[rupertrr]

I changed both slave and master clutch cylinders on my V8S. I can’t remember where the bleed nipple was (above or below) but I didn’t have to bleed it when I changed the master and slave cylinders - just left the nipple open and filled the slave cylinder reservoir and let it trickle through. Once it ran out the nipple with no bubbles it was job done. Maybe I was just lucky.

Edited by rupertrr on Saturday 17th April 15:28

[Sandgrounder]

Cheers Graham (Spanish S2), I may well try it as is and see if I can bleed it ok. If not, I'll have to rotate slave and struggle with access.

Rupertvr, I guess the V8S is a different set-up from the sound of it!!

[magpies]

the bleed nipple should be uppermost.

I changed the pipe to st st braided flexible hose too.

Edited by magpies on Sunday 18th April 10:10

[S2Andy]

I use a braided flexi pipe between master and slave. It is sufficiently long to allow the slave to be bled unattached to the bell housing. In fact I bleed it adjacent to the master cylinder under the bonnet, then fit it afterwards. So much easier.

[bil]

whilst looking for other things came across these,

noting the original arm/rod was retained like yours the new rod wasnt long enough.


and the new cylinder needed work to get it to match the original before it could be fitted.

[Fefeu52]

I replaced mine last summer. Bleed nipple was on top... and really tricky to access with the spanner.

[mentall]

Mine's at the bottom, and bleeds out easily enough.

I use a vacuum bleeder, just like this one

A good tip is to put some copper grease on the threads (just the threads!) of the bleed nipple. Then it doesn't suck air in when you release it to bleed, and it'll move easily next time.

[phillpot]

Given that air will rise to the highest point it really would seem logical to have the bleed nipple at the top

[mentall]

That's always been my experience too.

But there it is!

[Sandgrounder]

Thanks for the inputs all. Got it back together this evening and attempted to use my new bleed tool.

Bled it 3 times to be sure there was no air bubbles, and pedal feels ok, but haven't driven it yet, so still on axle stands. Will check in the morning then insure/mot and tax it before finally getting it back on the road.