Technical Massive hassle trying to bleed clutch

[x Alex x]

hey all!

helping a mate out earlier with a mk2b, his slave cylinder looked to be leaking a little so i offered to stick a new one on for him.. took it off and bolted the new one on but it just wont bleed!

it is the type where you can't turn the bleed nipple, you just pull the clip up and pull the clutch line out 10mm as i read on here but it just trickled out a few bubbles and that was it. clip back on and still no clutch :bang:

tried putting a pipe on it into some brake fuild as you would bleeding brakes and all it did was throw bubbles out, way more air than could be within the system.

we even tried putting the old slave cylinder back on and it wont bleed, kinda stuck now as his car is outside of mine and obviously he needs it

any ideas? my uncle has one of the air bleeders for brakes.. might give that a go but surely it shouldn't be this difficult, it was driving before the old cylinder came off..

thanks!

 

[Ziggy122]

That little clip does Yes come out - yes it should allow you to bleed it up with a reasonable pipe on the nipple to watch air escape

If you think its sucking air in - use grease to seal the area to prevent extra air

A pressure bleeder might help, but tbh punto slave cylinders dont usually let go

Ziggy

 

[x Alex x]

great thanks, the clip just lifts up and allows the clutch line to come out a little.. that's what i was doing.

to get the bubbles to come out i got him to pump the clutch otherwise nothing was happening

 

[x Alex x]

do i need to pump the clutch to bleed it though yeah?

 

[flisko]

press clutch and hold
your buddy opens bleed nipple on slave cylinder and closes it after few secs
release clutch
repeat till all air is out and you get a nice stream of brake fluid commin out

 

[x Alex x]

press clutch and hold
your buddy opens bleed nipple on slave cylinder and closes it after few secs
release clutch
repeat till all air is out and you get a nice stream of brake fluid commin out

great thanks for that

 

[x Alex x]

Still no clutch at all

 

[flisko]

Still no clutch at all

when you press clutch does that lever on gearbox actually move?

 

[x Alex x]

It has a few times but still not as it should with it being light until it reaches the bottom of the pedal.

Further attempts at bleeding looses it again completely

 

[Ziggy122]

Master cylinder not bled dry?

Maybe u will need a pressure bleeder or vacuum bleeder


Ziggy

 

[x Alex x]

Possibly but it must have had some fluid going around for it to get a little pressure halfway down the clutch and move the arm on the gearbox a bit

 

[judderbar]

If the system is working ok you should be able to pull the clutch hose all of the way out and pump fluid into a container without using a pressure feeding system on top of the reservoir.

When you take the clip out of the slave the hose comes out quite a small amount to enable you to bleed. 1 cm sounds far too much. It is just a slight feelable 'click' back from fully in and should be able to feel it lock into the bleed position when the parts are clean.

Another possibility here is the master is blocked up and it just so happened you had not noticed it. You probably will not be able to clean that out and you will need a new one. Not expensive but a bit of a job to replace. When my master got blocked up the pedal would slowly move to the floor after a few days of use and could not be pulled back up again. Undoing the slave end made the pedal spring back up as I recall. I probably had a small leak on the first seal so it travelled down slowly but could not refill. Maybe yours seals well but is blocked so you cannot refill it . Thinking about it now, my clutch pedal was loose for a long time before it became so bad i had to fix it and it is hard to notice it is a problem.

I am fairly sure there should be a fluid route from the brake master thru to the slave when the pedal is fully up. So if you leave the hose disconnected it should drip. That route enables the system to refill with fluid if there are leaks for example at the slave. No drip suggests the master is blocked. There are though two holes in the master? :-(

I cannot recall exactly how i did it now, but somehow i was able to refill my hose with fluid from the slave end - possibly i put the fluid container somewhere high and then pumped for a while and then allowed the air to travel up the clear tube i was using, and repeated till no more air came out.

 

[x Alex x]

many thanks for that, 10mm is deffinitely how much it comes out when you raise the clip, it has to come past the bleed nipple.. checked on here and someone else mentioned about 10mm too.

borrowing an easy bleeder on wednesday so i'll give it a bash then

who'd have thought it could be such a huge hassle!?

 

[judderbar]

many thanks for that, 10mm is deffinitely how much it comes out when you raise the clip, it has to come past the bleed nipple.. checked on here and someone else mentioned about 10mm too.

I checked mine. It comes out about 2-3mm to allow fluid to move up my tube without pumping.





Here is a video to show fluid rising up the pipe even with the pipe pulled out such a small amount

[ame]https://youtu.be/0dD4Jl8TeBI[/ame]

 

[x Alex x]

thanks for that, will have another look tomorrow as he's coming to mine.

wish they'd just used a proper bleed nipple! even when it works as it should it's not any easier.

don't think this is the issue with this car though, it must be pulling air in as a monumental amount of air was bubbling out and showing no sign of stopping, something is a miss somewhere i just didn't have masses of time last week

 

[judderbar]

thanks for that, will have another look tomorrow as he's coming to mine.

wish they'd just used a proper bleed nipple! even when it works as it should it's not any easier.

don't think this is the issue with this car though, it must be pulling air in as a monumental amount of air was bubbling out and showing no sign of stopping, something is a miss somewhere i just didn't have masses of time last week

If you are pumping air the problem must be at the clutch master end. There is a rubber hose between the brake reservoir and the clutch master about a third of the way up the brake reservoir. I think the hose just pulls off the clutch master. It could be blocked and broken perhaps??

Alternately it is just blocked at the master and you are sucking air in and out?

I did the work to replace the clutch master from the top which was fiendishly difficult and at the time i did not have a proper set of spanners and sockets and methods to be safely under the car. It was a mother of a job to get my hands in there anyway.

 

[judderbar]

I also did not know the correct way** to separate the plastic balljoint at the clutch pedal and ended up dismantling the thing and then damaging the metal ball on the new clutch master putting it together again. If you break that small white nylon clip you are looking at a replacement clutch pedal!!

** @Ziggy122

 

[x Alex x]

Still never really got it to bleed properly, he traded it in yesterday so won't ever find out the cause