Clutch Bleeding gone wrong!

Clutch Bleeding gone wrong!

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Discussion

Iwm86

Original Poster:

6 posts

65 months

Tuesday 4th December 2018
quotequote all
Evening all,

I've a query if you're not too busy at some point this evening. I'm driving a 2005 Renault Master, self converted motorhome.

After breaking down the other week, we had the slave cylinder replaced. Since then, the pedal had been a little soft in the mornings and would stiffen up after driving for a few miles.

I suspected some air in the line.
So this afternoon I topped up the reservoir, got my wife to hold down the pedal and I cracked the bleed nipple for a split second.

There was a slitter or mostly air and a little fluid...

The pedal never came back up.

I tried pressuring the system with a kit I have, but the fluid just won't go through the system. Nothing will come out.
I'm worried it's the slave again.
As it's similar, but this time there is no leaking (which there was near the gear box when the slave went).

A note: when they replaced the slave they also disassembled the master and put it back together again and said it should be OK.

The slave has done about 600 miles and the master has done about 3,000 (the previous slave had done 2,000 before breaking).

Diagnosis and recommendations would be appreciated.

I'm in Spain by the way.

UPDATE: Spoke to the original mechanic who fitted the slave, master and clutch kit in the first place and he said he had a real problem bleeding the system after fitting it all. He tried all sorts and had to borrow a battery powered bleeder from another garage.
Could this be what I need again? Or is this the result of another issue?

Cheers

steveo3002

10,535 posts

175 months

Tuesday 4th December 2018
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some can be a pain to bleed....ive had good results getting a large syringe and some tube and filling it with fluid then reverse bleeding from the slave upwards , just make sure theres room in the reservoir so it doesnt overflow

gunsun easy bleed is another one worth a look...cheap and works well

Iwm86

Original Poster:

6 posts

65 months

Tuesday 4th December 2018
quotequote all
Hi Steveo

I used an eezibleed this evening after the initial spurt of air and the pedal going flopy. Nothing. Had my wife pumping and lifting the pedal at the same time too. Still nothing.

It's the fact that I can't get any pressure to build that worries me. Do you think that's just a LOT of air in the system?

How would I know if the master has gone? Not that it should have. It was driving OK, before I attempted this.

I've heard of the syringe method. Do you keep the pedal down whilst doing this? Would you expect to see bubbles in the reservoir (as well as liquid pushing through)?

tapkaJohnD

1,945 posts

205 months

Tuesday 4th December 2018
quotequote all
"slave cylinder"? Doesn't a Master (don't all moderns?) have disc brakes all round?

It's not the pressure in the slave, or the calipers - apart from a little bit of knockback - that pushes the pedal back up, its a spring in the master cylinder. That's your doesn't points straight at that, never mind what was said when it was rebuilt.

You need a new master (cylinder!).
John

Happy Jim

970 posts

240 months

Tuesday 4th December 2018
quotequote all
tapkaJohnD said:
"slave cylinder"? Doesn't a Master (don't all moderns?) have disc brakes all round?

It's not the pressure in the slave, or the calipers - apart from a little bit of knockback - that pushes the pedal back up, its a spring in the master cylinder. That's your doesn't points straight at that, never mind what was said when it was rebuilt.

You need a new master (cylinder!).
John
Clutch sir (not brakes)

Ian Geary

4,496 posts

193 months

Tuesday 4th December 2018
quotequote all
Quite. I believe it's the springs built into the clutch cover that should return the clutch fork (and therefore pedal) to the return position.

The fact this force isn't being transferred via the 2 cylinders and clutch fluid would suggest that's where the problem is.

I think when the seals went in my slave cylinder, the fluid didn't leak, but the fluid was just passing around them.

Is there a way of testing the master cylinder is making pressure?

GreenV8S

30,213 posts

285 months

Tuesday 4th December 2018
quotequote all
Iwm86 said:
I used an eezibleed this evening after the initial spurt of air and the pedal going flopy. Nothing. Had my wife pumping and lifting the pedal at the same time too. Still nothing.
Exactly what were you doing with the bleed nipple while this was going on? Unless you carry the procedure out correctly, you could easily end up sucking air back into the system.

Iwm86

Original Poster:

6 posts

65 months

Wednesday 5th December 2018
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Morning guys,

So I went into town and found a pharmacy with some decent sized syringes. Came back and followed the directions.

Found it very tricky to pull the syringe. It may have been pulling air, but it might have been from around the thread.

A pitiful amount of fluid came out too.

I thought I'd try and inject some fluid in.

Made sure there was no air in the syringe. But it wouldn't budge. I didn't want to put too much pressure on the syringe, but none of the fluid wanted to go in.

I'm wondering if a double team of the eezibleed and the syringe pulling out air will do the trick?

I'm still not confident the master cylinder is working 100%.

It's getting to the point where I'd take it to a garage, but I can't even drive it. So annoying.

tapkaJohnD

1,945 posts

205 months

Wednesday 5th December 2018
quotequote all
Clutch! Clutches face!

But same difference, even if the clutch spring(s) had failed, that the master won't is due to spring failure there.

John

Iwm86

Original Poster:

6 posts

65 months

Wednesday 5th December 2018
quotequote all
I had a whole new clutch kit 3000 miles ago. 😩

sparkythecat

7,905 posts

256 months

Wednesday 5th December 2018
quotequote all
Iwm86 said:
It's getting to the point where I'd take it to a garage, but I can't even drive it. So annoying.
If you can, plan a route to a garage that won't involve bringing the vehicle to a complete stop before you get there. Then get a couple of helpers to push the beast while you crank it up in first gear to get it going. Rev matching and gentle gear changes should get you there without a clutch.

JoeBolt

272 posts

163 months

Wednesday 5th December 2018
quotequote all
Is there another bleed nipple anywhere in the system?

As an example, I have an old Nissan Primera which has a 'Clutch Damper' in the line between the Master and Slave cylinders. This damper has its own bleed nipple which (as per the manual) must be bled after bleeding the slave cylinder.

InitialDave

11,928 posts

120 months

Wednesday 5th December 2018
quotequote all
I have had some odd behaviour where the master cylinder had slightly too long an actuator rod on it, so while it all fitted fine, the master piston was always a little depressed, and the port to let fluid in from the reservoir wasn't clear to do so. Worth a look.

In practical terms, consider the approach of pushing fluid "backwards" up the line, only this time slacken off the union for the pipe to the master? If it works then, and squirts a bit out the opened joint, I'd say it's a master problem.

For bleeding in general, if you have a compressor, I use an air powered vacuum bleeder, I find it works really well, even on Land Rover 109 front drums, which are notoriously hard work.

sunbeam alpine

6,946 posts

189 months

Wednesday 5th December 2018
quotequote all
Reverse bleeding the system should be easy enough - as long as you can get access to the slave cylinder.

You just need to crack open the bleed nipple, attach the syringe (I use an old pump soap dispenser), and pump fluid into the system.

This works well because it pushes the air out of the system (air wants to go up).

wolf1

3,081 posts

251 months

Wednesday 5th December 2018
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Pretty standard for a renault van clutch hydraulics. Unless you know how to do it correctly then leave well alone as you'll only waste loads of fluid and frustrate yourself. We always back bleed them but the syringe we use is 300ml and heavy duty. Your only real option is get it to a garage and let them do it.

Iwm86

Original Poster:

6 posts

65 months

Wednesday 5th December 2018
quotequote all
I spent about 5 hours on this today, and I'm done with it.
I won't bore you with the details, but the only time I managed to get any fluid through the bleed nipple, was when I bypassed the master cylinder and put pressure through the reservoir.
I think the master might be the block in the line, but I'm spent. I took it to pieces and i can't get fluid to flow through the inlet.
Got it booked into a renauly garage for Friday. I'm worried I've done no end of damage, so I'm hoping the pros can do a better job than me.

I'll mention the idea above and tell them what I've tried. See if they can shine any light on it.

Caddyshack

10,849 posts

207 months

Wednesday 5th December 2018
quotequote all
Pump the fluid up, backwards, through the bleed until the reservoir overflows...job jobbed.

Iwm86

Original Poster:

6 posts

65 months

Wednesday 5th December 2018
quotequote all
Been there, tried that. There's no budging it. Like I said, the master cylinder seems to be blocking the way.

There are a few sections in the line that can split apart. I've had them open and fluid flows nicely through. Just something not quite right somewhere.

I'll let you know how the garage goes.

GreenV8S

30,213 posts

285 months

Wednesday 5th December 2018
quotequote all
By any chance have you adjusted the pushrod on the master cylinder so tight that it stops the piston withdrawing fully? If so, the circuit would never be open to the reservoir so eezibleed type systems wouldn't work.

slybunda

143 posts

65 months

Thursday 6th December 2018
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i used a vacuum bleeder to do the job,
https://www.ebay.co.uk/itm/HAND-VACUUM-PUMP-HELD-B...

like one of those. works well if you cant pressurize from where you put the fluid in.