Any BTDTs ? - How hard is it to manually activate the master brake cylinder

[Kenn Thyrsted]

Well i didn't know it couldn't :-)
What i had done was getting the rubber / o-ring things renewed, and then they
bench-tested operations.
Now i wish i just bought a new one, then.

Yes, i don't know how this hydraulic booster is designed, but i imagined
something like maybe with the wear and tear, somehow the thinner pentosine
(when hot) could bias the booster a little, and then when i press the brake ,
the feeling is a hard pedal, but it brakes ok. unfortunately it will not
release pressure again, until cooled down by eg. water.


----- Original Message -----
From: "Kneale Brownson" <knotnook at traverse.com>
To: "Kenn Thyrsted" <thyrsted at e-box.dk>
Cc: "Quattropedia" <quattro at audifans.com>
Sent: Friday, July 13, 2001 7:32 PM
Subject: Re: Any BTDTs ? - How hard is it to manually activate the master brake
cylinder


> I didn't think these alloy mastercylinders could be rebuilt
> successfully.  If pouring water on the MC releases the seized brakes, you
> need a new MC.  Don't know about the hydraulic brake booster holding
> pressure after the pedal's released.  Is that what you think was happening?
>
>
> At 05:30 PM 07/13/2001 +0200, Kenn Thyrsted wrote:
>
> >Well.. I had a problem with sticking brakes when hot, and as i've had the MC
> >rebuilt 2 years ago, -and- as the problem dissapears when i cool down the
> >hydraulic brake-servo, i told him to swap the old hydraulic brake-servo with
a
> >new one.
> >Maybe i didn't have to do that, - seemes as i'm in for a new MC. (too) :-/
> >
> >/Kenn
> >----- Original Message -----
> >From: "Kneale Brownson" <knotnook at traverse.com>
> >To: "Kenn Thyrsted" <thyrsted at e-box.dk>; "Quattropedia"
<quattro at audifans.com>
> >Sent: Friday, July 13, 2001 5:23 PM
> >Subject: Re: Any BTDTs ? - How hard is it to manually activate the master
> >brake
> >cylinder
> >
> >
> > > I've never "pumped" a new one by hand prior to installation, but old MC's
> > > I've replaced will squirt residual brake fluid just like a squirt gun
with
> > > just a little pressure on the rod.  Why did he remove the MC if your
brakes
> > > were working fine on the drive to the garage?
> > >
> > >
> > > At 04:49 PM 07/13/2001 +0200, Kenn Thyrsted wrote:
> > >
> > > >Hi all
> > > >
> > > >I'm having my '87 200 TQW in for a clutch job, and for some brake -
> > fixing.
> > > >Now i have a question:
> > > >How hard is it to manually push the piston in on the master brake
cylinder
> > > >when
> > > >it is off the car ?
> > > >My mechanic says that mine is stuck, - he can't move the rod at all.
> > > >He states that you usually can do that, on normal brake cylinders. And
> > that
> >he
> > > >can not imagine that the hydraulic servo is using more power than he is
> > > >applying..
> > > >
> > > >However, - I drove the car to the repair shop 14 days ago, - brakes
worked
> >as
> > > >usual.
> > > >The mechanic is baffled too.
> > > >
> > > >Could it really be stuck ?
> > > >Any hints would be appreciated !
> > > >
> > > >Kenn Thyrsted
> > > >'87 200 TQW
> > >
> > >
>
>