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Discussion Starter · #1 ·
I must be doing something wrong when installing new master cylinder.

I'm using NooNoo's excellent DIY

My first master cylinder (new from JPGroup) failed during bleeding. The plastic collar is broken. Not sue if that was how I got it or if pressure during bleeding made it break.
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So I bought a new one from Luk.
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Installed it yesterday and noticed that even with the metal clip pushed all the way in, the elbow part slides up and down 1-2mm. Doesn't matter how hard I try to push the elbow up into the master cylinder connector, it doesn't seem to click in & always has that 1-2mm up down movement. Actual clutch pedal assembly is bolted into place. Even got 3 new self-locking nuts!
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When bleeding, not surprisingly, it leaks at this join. Any ideas would be appreciated.

Northpole, no it wasn't broken to start with. Pedal worked perfectly well. Even bled the system after the new clutch was installed. I stupidly decided to replace it as part of a new clutch job. Been regretting this for 6 weeks (takes a while for new parts to come from Latvia to Australia).
 

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than the supplied luk is defective... as i think back to when i did mine when pushing on the pipe you should feel it lock into the housing... than you push down the circlip( locking clip) that should be the end of it leaking... but if you don't feel it lock itself in place than it's faulty.
 

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Discussion Starter · #7 ·
Thank you to all. Adam, is there 2 seals? One on the elbow (#7) in Northpole's diagram and second #28 in parts diagram below?
28 02F 141 143 A o-ring 9,25X6,07X1,78
28A 02F 141 143 A o-ring 9,25X6,07X1,78
(28A) 1K0 721 741 o-ring

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Old seal looks the right size, internal seal to the master good?
it's why i said the new one must be faulty as it should have the internal seal installed... they never come separate and i had to change them twice on my own car, and did 4 others that weren't mine... and only once did i have a leak like that ( cheap Chinese copy bought by someone else) but he ended up buying one from eurocarparts and that didn't leak.
 

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Interesting my OH's Caddy was leaking on a totally stock OEM setup - hadn't been disturbed AFAIK. May of had a clutch.

Anyway, started to leak and I padded out the OEM seal on the pipe with a rubber o-ring behind it. Used it to 'push' the OEM seal further towards the end and it sealed up fine.

Pure pikey but it's held for 20k sooooo.
 

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Discussion Starter · #11 ·
Thanks for your patience. I ripped apart the master cylinder with broken neck. There is no second seal. There isn't a groove for one either. I'll fiddle around some more hopefully on the weekend. Maybe I'm not pressing the elbow into the master forcefully enough....

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Discussion Starter · #12 ·
I think I've done it. I pulled the pipe of both brackets at the fire wall to allow the elbow more movement.

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I was then able to easily push the elbow into the master cylinder. And yes, it gave a rewarding click. Pushed circlip in, and no movement. Pressing the clutch pedal down, doesn't make it leak and what's more, pedal returns to up position by itself. After work I will bleed the system. Then need to reinstall coolant reservoir, top up fluids and reinstall everything else above the gearbox.

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It's been a while since I looked inside one tbh, so I might be wrong about the internal seal. Swear there was one though, but I'm getting old so probably wrong.

So it just wasn't home all the way?
 

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Discussion Starter · #14 ·
Yes, suspect elbow hadn't gone in all the way.

1st round of bleeding went well. No leaks. Pedal not coming back up by itself, but I'll have a second go tomorrow.
 

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Discussion Starter · #17 ·
I had a coolant leak. Eventually pulled out entire thermostat housing and reseated o-rings and redid connections. Started car up but had another coolant leak. Redid one of the connections and all seems well. I've started a thread on member rides but is incomplete. Cheers
 

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Greeting from Oz lads
Was trolling the net looking for answers to a similar problem and found this discussion.
The clutch died in a 2001 1.8L GT.Was thinking slave cylinder. Incorrect fluid was low topped it up and when i pumped pedal fluid sprayed somewhere just above the elbow as depicted in photo.
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Pulled unit out thinking it was cracked but i cannot see it. Over $300 Australian dollars for a replacement master and I'm not 100% sure that is the issue.The strange thing is in the photos posted by Arec_p there is an elbow that clips into the master cylinder.In the exploded views posted by both himself and north pole they do not show the elbow.Here in Australia the VW dealer says it must be a modification as they have no elbow on their diagrams.I was going to buy an elbow first just in case there is nothing wrong with the master cylinder and the spray is coming form the elbow or o ring leaking (only 30 bucks for that kit)
Any info will be appreciated.
Cheers
Steve
 

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Discussion Starter · #19 ·
Where are you redmick? I'm in Brisbane.

I replaced my master cylinder as part of replacing the clutch etc. There were no problems with it. I caused a leak between master cylinder and the elbow because elbow wasn't plugging in properly. In a V6 there is very little working space.

I found (perhaps I didn't explain it well) that when I disconnected the copper pipe from the firewall brackets, I had much more room. The elbow plugged in perfectly. No leak. Been driving for few months. All good.
 

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Hello Mate I'm in Leeton NSW
With this one the clutch just collapsed all of a sudden.
To me the elbow has movement up and own but i guess as long as the o ring is in the right area it should not matter as the clip holds it where it should be .It was spraying out as soon as i filled the fluid and pumped it.It is a 2001 1.8 GTI.Short story is I'm fixing it for GF son as she would end up paying the cost for repairs anyway so trailered it back from Wagga to sort it out myself.
The dealership suggested it might have been modified i said nah mate i doubt it. And then i found your photos proving it was factory.I know I'm gunna put an orange in then the bugger will spray again but at least i will have proved it before spending the dollars at Bursons or Repco.
 
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