I had the same problem last year on my 1996 850. On the first pedal pressure
the
pedal travelled far and I felt that there was little resistance and on the
second pedal
pressure it was ok. Found that my front disc's was below limit in one front
side and
this was caused by a slightly hanging (lazy) caliber. Changed the front
calipers and
the front discs and everything went like new again.
> Anyone any ideas and comments about this one. 1996 volvo 850 2 litre 20
> valve. Sent it into the mechanic, brakes very spongy becoming harder with
[quoted text clipped - 14 lines]
> Any comments and suggestions gratefully accepted. Sorry for the longish
> post! - Roy
"Roy Bolton" <hibasog@ntlworld.com> wrote:
> Anyone any ideas and comments about this one. 1996 volvo 850 2 litre 20
> valve. Sent it into the mechanic, brakes very spongy becoming harder with
> the next press of the pedal.
If the rotor is warped, it pushes the pistons back causing more pedal
travel. Wear does not cause this since the pistons should stay just
slightly above the surface no matter where that surface is if there is
no wobble in the rotor. Of course air in the line will cause sponginess
but that usually doesn't go away when you pump the brakes.
By the way, the main causes of warped rotors are improper torquing of
the lug nuts and high speed stops.

Signature
Cheers, Steve Henning in Reading, PA, USA
Owned '67,'68,'71,'74,'79,'81,'87,'93,'95 & '01 Volvos.
The '67,'74,'79,'87,'95 and '01 through European Delivery.
http://home.earthlink.net/~rhodyman/volvo.html
many many years ago when I drove cabs for a guy who used to swap around pads
and use retread tyres I had brake problems too .He employed a partimer on
the week end who flogged the car and the brakes were bad news on Monday .So
I found heating them up a bit and cooling them down slowly seems to remove
the issues ,he was an ex cop ex navy and ex security guy so he pushed the
cab hard .I owned several cabs new tyres (safer and cheaper in the long run)
quality brakes and if a part timer warped them a bit I made sure I heated
them up and slowly cooled them then if needs be had them machined .Keep the
brakes off the hot spot by just moving slowly at the lights just a few
inches so there is no extremly hot spot to warp them dont just stop and turn
the motor off the brakes will super heat one spot and problems will occur
.$60 quid to bleed brakes wow thats high .
> I had the same problem last year on my 1996 850. On the first pedal pressure
> the
[quoted text clipped - 25 lines]
> > Any comments and suggestions gratefully accepted. Sorry for the longish
> > post! - Roy