VW Golf master cylinder failure - what would cause it?

[Ross]

Hey guys,

A non-S2 question here. Just managed to make the last miles into work with a clutch pedal on the floor... fine on the open road but coming through town was a bitch.

Anyway, I've had this problem twice already in my ownership with the car - both times a master cylinder failure - and lasted almost exaclty 10,000 miles.

I put the first problem down to 130,000 miles and the second a dodgy part (was replaced under warranty). However a 3rd failure has me wondering what would cause such a problem. Anyone got any ideas?

Cheers
Ross

[Jamo]

What MK2 golf?

You could look in my 2nd forum home http://www.golfgtiforum.co.uk

[Ross]

It's a Mk4 GT TDI PD130... booked it in at a garage down the road, hoping they can sort it this afternoon otherwise I'm working till rush hour is over and practicing some more clutchless shifting.

Just trying to figure out what might cause a master cylinder to fail so often, so I can replace that too (pls don't say a worn clutch! )

[slow2]

It's a Mk4 GT TDI PD130... booked it in at a garage down the road, hoping they can sort it this afternoon otherwise I'm working till rush hour is over and practicing some more clutchless shifting.

Just trying to figure out what might cause a master cylinder to fail so often, so I can replace that too (pls don't say a worn clutch! )

Worn / broken spring in clutch presure presure plate or release bearing
sorry Ross but thats what it sounds like

[jameswkr]

Sorry. Cannot see how the clutch itself will affect the master cylinder (but had a new clutch diaphragm overcome aged master/slave cylinders). Suggest that the clutch lever/pushrod is somehow affecting the master piston/seal/cylinder orientation. Assume you are using the correct fluid. Has the car been crashed? Bulkhead damage? Sure its the master and not the slave ? Pls let us know how it turns out. Good luck.

[GazzaG60]

is there air in the system?

does the mk4 share the same fluid res.

if so id do as full bleed and check the piping too.

ive had masters and slaves fail in the past. have you replaced the slave too?

if the slave is leaking past fluid, whihc mine did when i went on the clutch it would work then over aruodn 15 seconds it would engage and start to try to move the car forward if in gear.

what tends to happen is fitting a new master or slave makes the other work harded and in turn brings on failure. best to replace both.


do you hear any noises that go away with a little depression of clutch. if so you may have thrust bearing issues. dont expect them to be the cause

[slow2]

Sorry. Cannot see how the clutch itself will affect the master cylinder (but had a new clutch diaphragm overcome aged master/slave cylinders).

Sure its the master and not the slave ?

Anyway, I've had this problem twice already in my ownership with the car - both times a master cylinder failure

[Pirvu Eugen]

Brake fluid or free play off the brake pedal.
I found out that because the return spring from the pedal was broke... they said is the master cylinder.
hope this helps!

[Ross]

Well just spent an hour outside with Mr. Recovery; abandoned the garage idea when they said they'd have to replace the clutch at a cost of £668.39
(and that was if the notorious DMF can be re-used)

Anyway it's been checked, bled, piping checked etc etc and the recovery fella has given up and gone home. Aparrently 'roadside assistance' means that they do everything they can to fix it first Hopefully, a tow truck will be here some time this side of christmas

The "good" news is, a local VAG independent have parts in stock if the new clutch is required and can look at it tomorrow. I'll keep you posted!

[volcano rs]

you don't have much luck with cars do you ? try alternative transport

[4WheelDrifter]

Are you sure they're not pulling your leg? Sounds just like a broken clutch pedal. They break all the time too, so it would tally with the frequency of the failure. There's usually some broken plastic in the footwell when it breaks.

[volcano rs]

Are you sure they're not pulling your leg? Sounds just like a broken clutch pedal. They break all the time too, so it would tally with the frequency of the failure. There's usually some broken plastic in the footwell when it breaks.

if this is same as mk3 golf then it could be the peddle box where master cylinder sits the little metal part breaks away and allows master cylinder to push through instead of locking into the plastic bit .this problem also exists on A3 .
the peddle box needs to come out and re welded rather than buying a new one which will end up same again .

[4WheelDrifter]

if this is same as mk3 golf then it could be the peddle box where master cylinder sits the little metal part breaks away and allows master cylinder to push through instead of locking into the plastic bit .this problem also exists on A3 .
the peddle box needs to come out and re welded rather than buying a new one which will end up same again .

Yeah. It's the same on the A3 and S3. BTDT too many times. I keep meaning to get an old pedal welded up, as the stock ones are *****.

I've just spoken to Ross and this sounds more like a dual mass break up, I hope not though, BTDT too.

[Crawford_S2]

Hmmmm, DMF is a right ball ache to get off when it goes tats Seen a few go this way and they ned to be totally butchered to get em off

Hope it ain't too ££££££££ for you dude, and as^^^^^^^ maybe a hilux or something really indestructable with your luck eh bro

[avants2turbo]

im pretty sure you can replace the DMF with a normal one off say a mk3 16v (228mm, 6 bolt) and use the clutch to suit, VR6 pressure and friction plate?

Ive got a hydraulic clutch on my mk2 Golf VR6 and have never had any issues with the hydraulics..