T6 140PS 6 speed clutch master-cylinder replacement [Guide]

[Chrishall888]

Hi folks,
I’ve changed the master cylinder today on our T6 140 6 speed and noticed it has not been published before.
Hope it helps:-

1: open the bonnet and remove the wiper arms. These can be stiff but with a wiggle up and down usually frees the off. If problematic get a small puller.
Pull the seal off and the wiper cover pulls off
2:securing a harness is a double threaded bolt with a 13mm head. Remove- this olds the top of the clutch pedal.

3: when you’re under the bonnet, pull the supply pipe off the side of the brake/clutch master cylinder
4: with a long nose set of pliers, release the silver clip retaining the clutch supply hard pipe from the master cylinder. The clip stays in place and withdraws 10mm or so.
The pipe, with a little tug comes out the bottom of the cylinder.

5: under the dash, release the kick panel from the clips. You don’t need to separate the column cover from the upper cover, as it comes out in one peice.

6:remove the brake and clutch brace: 2x 10mm nuts. Only need to slacken.


7:release the lower nut:13mm

8:release the right nut to bulkhead and electrical harness.

9:depress the clutch slowly and remove the whole pedal assembly.

10: on the bench: release the supply pipe and remove the foam packing

11: using two screwdrivers, release the white clip from the pedal.this is a tricky bugger but persevere, it comes off!

12: release the 2x mounting bolts (13mm) and electrical harness


13: remove the cylinder.
14: instal new cylinder and reattach pipe and foam.
15: install foot pedal to van and reverse the above procedure.
16: top up brake fluid and place gear selector in 4th.
17: with assistance bleed clutch.

 

[Quest Carlsbro]

Hi Chrishall888,​

Great instructions except that I can't get the clutch supply hard pipe out. I've withdrawn the clip the requisite 10mm but it seems solid in there.
I have actually disconnected everything else and all is loose.
I've tried gripping the hard pipe and getting a screwdriver between the plastic and pliers and twisting but it doesn't seem to want to budge, any ideas?
I was a mechanic in my earlier life but I suppose I'm getting on a bit now

 

[Chrishall888]

Hi Chrishall888,​

Great instructions except that I can't get the clutch supply hard pipe out. I've withdrawn the clip the requisite 10mm but it seems solid in there.
I have actually disconnected everything else and all is loose.
I've tried gripping the hard pipe and getting a screwdriver between the plastic and pliers and twisting but it doesn't seem to want to budge, any ideas?
I was a mechanic in my earlier life but I suppose I'm getting on a bit now

Ah the bloody oring can get a good hold in there!
Spray it with some wd40 or lube and give it a tap upwards with the plastic hammer, as close to the bend as possible.
I wouldn’t suggest using a screwdriver or such on the collets, as they will be quite brittle and potentially crack if touched!

 

[Geeky Philip]

Thanks for this guide.
Can you give me the part number for the master cylinder?

 

[Chrishall888]

T6 Transporter Clutch Master Cylinder 7E0 721 401F

 

[Geeky Philip]

T6 Transporter Clutch Master Cylinder 7E0 721 401F

Thanks

 

[matt_grix]

Hi, does anyone know the differences if any between 7E0 721 401F and 7E0 721 401E...

Been looking for a new Master Cylinder, and can find a Valeo part for a Transporter at E level, but unable to find anything for F... The difference is £46 for E to £126 for F so if it is just an upissue for Supplier change i was wondering if they were interchangable?

 

[Chrishall888]

I suspect the earlier number is without the pressure sensor, which also has a steel enclosure.

 

[ducopo]

merci pour ce tuto ^

 

[parts+labour]

Just wanted to add to this excellent guide by Chris, that I have just used.. Thank you!

The bleed point for the clutch hydraulic line is on this block, which also acts to limit the speed of the fluid flow. It's just outside of the clutch housing. It needs a 1/4 turn to open. It is very stiff and needs a 13mm spanner or AJ on it. Space is tight and it's a pain in the hoop! Someone on another thread suggested pulling the clip out of the nylon part to make it turn easier. Do not do this! If the nylon part pops up you'll be in a world of pain and will not be able to sort it without removing the whole valve and nipping it all back together in a vice. Speaking from bitter experience!



Also, I would say that it's a good idea to have some spare o-rings/seals for the pipe connections in stock before you do the job.


OEM part number below. Also available in bulk packs from Amazon

1K079874​

 

[parts+labour]

Just wanted to add to this excellent guide by Chris, that I have just used.. Thank you!

The bleed point for the clutch hydraulic line is on this block, which also acts to limit the speed of the fluid flow. It's just outside of the clutch housing. It needs a 1/4 turn to open. It is very stiff and needs a 13mm spanner or AJ on it. Space is tight and it's a pain in the hoop! Someone on another thread suggested pulling the clip out of the nylon part to make it turn easier. Do not do this! If the nylon part pops up you'll be in a world of pain and will not be able to sort it without removing the whole valve and nipping it all back together in a vice. Speaking from bitter experience!

View attachment 263415

Also, I would say that it's a good idea to have some spare o-rings/seals for the pipe connections in stock before you do the job.

View attachment 263416

 

[The Bear78]

I've just removed my clutch pedal using this guide. Fantastic work @Chrishall888

I did struggle a bit just getting the pedal assembly out after everything was undone. Like on yours, there appears to be a redundant bracket for a switch on the back of the steel housing, possibly from an older model. This fouled the cable support bar under the dash. I cannot see it in your photos but assume is standard across all early T6's (mines a 2016 140). A bit of brute force to bend this out the way and all good.

​

I've tried gripping the hard pipe and getting a screwdriver between the plastic and pliers and twisting but it doesn't seem to want to budge, any ideas?
I was a mechanic in my earlier life but I suppose I'm getting on a bit now

For future reference, this worked for me. A point worth mentioning is that the pipe ferrule is quite large so you can only lever against the very outside of the master cylinder socket. See below...



Also, there is a rubber seal that sits on the end of the pipe. Don't let this fall down behind the heat shielding...



Another observation, the metal support bracket in front and slightly left of the master cylinder is only attached by two studs on the underside of the scuttle. 10mm nuts on these, removal will allow the bracket to be pushed to the side a little for better access to disconnect the hard pipe.



And finally, I did all this to replace the master cylinder after finding the pedal sat on the floor. There were no obvious leaks and with no resistance in the clutch pedal (other than the overcentering spring) I assumed the MC to be at fault.
I popped the plastic supply pipe off the MC and was surprised to see no drips. The level was well above minimum and I know that the pick up it higher than for the brakes but there was no flow.
I pulled the strainer out of the reservoir to take a look inside and saw the little chamber which isolates the clutch supply. I had to add fluid to over this level before it started to flow.



The chamber was not getting fluid. It seems that unless the level is near to the maximum line, the clutch may run dry...





I have a new MC on the way from LL Parts and as mine appears to be stuck down, I decided to just carry on. I needed to remove it to fix it so, at 155k it's probably beneficial to replace it!
I am concerned where the oil has gone so, hopefully it isn't actually the slave cylinder...

 

[The Bear78]

Shiny new parts....

 

[DXX]

And there was me thinking I had an aluminium master cylinder because nobody would be stupid enough to cut costs and make it in plastic.

 

[The Bear78]

I'm optimistic that it's lined with metal... maybe.

 

[indy4x]

Lost my clutch pedal today, no loss of fluid and was unable to power bleed

Bought a new master cylinder today and am in the process of replacing the old one

I have a 10mm dia metal bar that runs across the clutch pedal that is stopping me getting the pedal assembly out

Looking at the pictures in this thread I couldn't see the bar

This is what I have



Can't remove the bar as its welded to a big metal bracket that ain't coming out easily

Anyone come across this?

 

[The Bear78]

Yes. I had the same problem.

I found a big ring spanner quite useful to bend it out the way... you'll need to bend it back to refit the trim though. The videos I watched did not mention this being a problem, but I could not get the cylinder out otherwise.

Hopefully the master cylinder is the culprit.