Technical Brake Master cylinder seals ???

[martyc5674]

Gents
My pedal has started going to the floor...
Suspected a leaky rear cylinder but on removing the hubs this eve this is not the case... Also it's possible to press the pistons back into the cylinders on both sides.
Did the usual bleeding routine put pedal keeps sinking and both back brake cylinders are returning home and not staying out against the shoes.
No leaks or oil loss....
It's the master cylinder isn't it??!
Possible replace the seals??...
If I replace the master cylinder am I likely to brake pipes?
Anyone got a spare for sale?
Cheers
Marty.

 

[widemouthfrog]

What about this one?

http://www.ebay.co.uk/itm/Fiat-Mult...arts_Vehicles_CarParts_SM&hash=item2319fa9cee

 

[martyc5674]

Yeah...
I'm just trying to decide/figure out that that's my actual problem first!!
As you can see from my thread below I've already a big shopping list and money is tight
Anyone have master cylinder problems here been able to replace seals?

Also noticed there was a significant vacuum in the brake fluid tank.

About a month ago I had a weeping cylinder which gave the same symptoms(sinky pedal).
Replaced that and all was well.
Also the pedal now just sinks half way down and stops... Then the brakes pretty much let go till you pump again.
The ABS kicks in like hell if I slam the pedal even though there's no skidding but it was doing that with the leaky cylinder aswell.
Marty.

 

[widemouthfrog]

Vacuum in the header tank? Have you tried a test drive with the header tank cap left a little loose to see if that makes any difference?

 

[martyc5674]

I did just that... No difference.
Marty.

 

[martyc5674]

Ive ordered a new master cylinder from Germany.
Is there a good chance the brake pipes will break when disconnecting them from the old one??
When i was replacing rear wheel cylinders they broke at every union!!

Marty

 

[momoe]

Master cylinder is tucked away behind the subframe, making it a complete bugger to remove. If it's the seals that have gone, you can get away with removing the innards and replacing them with the new ones.

There has been a thread on here about how to do this but I can't find it.

 

[martyc5674]

Seems relatively accessible(from a multipla point of view)..
subframe momoe??...bulkhead you mean??

No doubt it will be a pain in the arse to remove...i just hope the pipes dont break.

The one im getting is
http://www.lpr.it/e-idraulicascheda.asp?LPR=1934

The one in it is by lucas so not sure the seals would be direct swap...plus i dont think id be 100% happy doing that...this logic could change

Marty

 

[martyc5674]

Master cylinder arrived Friday and I put it in today.
Just an update for others I suppose.

First... You don't need to go near the pedal/ inside the car at all

Secondly the master cylinder comes out without having to remove the servo.
The pipes came off easy... Two rubber pipes that go in the top from fluid tank just prise off... They were a bugger.
Whole system needed a bleed afterwards... Air at all 4 wheels and lots of it!!
It was an easy job... Took an hour max and that included a bit of hesitation with the rubber pipes.
Anyway all is well again ... Pedal is hard and brakes are good for first time ever.
Replacing disks/hubs and pads shoes during the week so hopefully I'll have good brakes for a while to come.
Marty