E30 Zone

I've got an issue with the Golf Mk2 1.3 servo and Audi master cylinder on my E30 S50 3.0.

Problem is that after a few miles all brakes gradually lock on until they seize.
See my video and pic of when it very first happened to me:



YouTube video http://www.youtube.com/watch?v=Ru4C5TH5o3A

Anyway, I've tried various items and even replaced the master cylinder, servo, diagonal routing of pipes (and parallel), adjustments on the inside servo pivot bracket, thread transfer bar.

Then the problem hit me;
When installing the master cylinder, you really have to push very hard to get it into the servo (sometime enough that a second person could be helping hold the master cylinder in place whilst you fit the nuts).
As I was pushing the master cylinder into the servo, brake fluid suddenly squirted out of the master cylinder ports. Strange I thought...... went and checked and E30 master cylinder and servo setup and it fits with no pressure needed at all.

E30 cylinder on the left and Audi cylinder on the right:


Depth difference:


So basically what's happening is that the piston in the master cylinder is having to be depressed when fitting just to fit it into the servo, which means the brakes are slightly 'on' even before its been bled, which is strange as the car is very free moving for the first 5 mins / 2miles driving until it starts to seize on and within 2 mins - your going no-where!

Anyway, I must have either the wrong servo or the wrong master cylinder. Here's some more pictures of the Golf servo and the Audi master cylinder:

Servo:


Servo pushrod flush with the servo opening for the master cylinder:



Audi master cylinder '25ZV' which i think is the correct one. This picture shows it in its position before pushing into the servo (its just located itself on the 2x servo studs) at this point it is about to need force to get it any further in:


On with 1 nut. Now the master cylinder piston has already been depressed to get it in this far. So its under tension and 'sprung' already:


Both nuts on and more pressure needed to get the master cylinder into the servo, whereas i think it should be able to be 'placed' in without any pressure needed from your hands.

Can anybody confirm this please?

Does it look like i have a wrong master cylinder or servo, or both?

Quick fixes (if even possible) seem to be cut/shorten the servo pushrod, or drill deeper into the master cylinder.

Only problem is that it's currently Thursday morning and tomorrow afternoon (Friday) i'm meant to be leaving Bristol to a trackday at Snetterton on Saturday.
So as you can imagine i'm in a rush and pulling my hair out as i'm running out of idea's.

Your thoughts please.....

Cheers
James

Can you not get hold of a Clio servo?
I fitted a 23mm Audi M/C and Clio servo to OBs`s M50 not long ago and it is perfect.
Mine has a Clio servo with standard E30 M/C and it is perfect.
Benjys is fitted with the same as mine and that too is fine.
I used the Golf servo/E30 M/C on my first M50 and pedal feel never felt that great to be honest.Was nice firm pedal to press but stopping power wasnt anywhere near as good.

Is there any adjustment on the rod coming out of the servo!!

Is the servo deffo off a 1.3 golf ? When using this servo with an e30 master cylinder a spacer is needed but when using the audi m/c the length should be correct.

servo looks like one I had the same issues with..

Get a plastic wing clio one..

Thanks for the reply's guys.

Ah so it seems like it probably isn't the correct servo then. All it says on it is Golf 2 (no mention of which engine model it's come from)

Ok so can anyone remember is the plastic winged clio servo has the pushrod set back inside the servo (when at resting position)

I.e here is the Golf servo and the pushrod sits flush with the servo opening (which is too long):



So hopefully the plastic wing clio has a pushrod that is set back inside the servo slightly (probably by 15mm ish?)

What sort of year clio should i be asking for?

Thanks for your help
James

er... plastic wing year.. Don't do french scrap sorry!

My servo (not a clio one though) has the pushrod set back though yes

Excellent, thats cleared things up. Thanks for the confirmation Jhonno!

I've got a trackday this saturday (2 days time)
I don't suppose anyone would be interested in selling me one or even loaning me one for the weekend. Any S50 guys have a spare one?
Quite happy to pay or drive to collect tonight as I need one by tomorrow morning.

As you can tell...... yes I am desperate

Cheers
James

Plastic wing clios are S plate onwards (1998) and look bug-eyed, should be plenty in local scrappers.

Good to hear you found out the problem. Was enjoying your right up in the other section and was wondering what had gone wrong, Hope this sorts it