<E28><E34><M5> Squishy brakes

[ingraham@xxxxxxxxxxxxxxxx (Curtis A. Ingraham)]

Adrift in a sea of vulgar profanity (Tim Gergen) and commercial 
vulgarity (Mark Kibort) in BMW Digests v09.n573 and n574, Jerry Chyo 
<jerryc@domain.elided> wrote:

> I replaced the fluid and pads this weekend with Metal Masters and 
> Castrol Dot 4.  I used one of those One-Man bleeders (the type that 
> attaches to the bleed valve and has a valve at the other end that 
> allows fluid to flow out, but not in). ... I now have squishy brakes 
> and I'm hoping to isolate the problem.  It could be 3 things as I 
> see it:
>
> 1. Crappy bleed job
> 2. Diff between Metal Masters and Jurids
> 3. ABS

Putting new pads against old rotors can cause weak, squishy feeling
brakes until the pads wear to fit the ridges on the rotors.  That
wear ought to happen in a few days.

Equally likely is incomplete bleeding.  I've done it the old-fashioned
two-person pump the pedal way, the one-person check valve way, the 
one-person hand vacuum pump way, and the pressurized reservoir one-
person way.  The two-person way has always produced good results for 
me.  I threw away the check valve bleeder after one use.  I gave up 
on the vacuum pump after the second use.  The pressure bleeder is
almost as good as the two-person method, but much more convenient.

Brake lines are rubber, and rubber parts deteriorate with age.  New
rubber lines might improve the pedal feel.  New teflon or kevlar
lines will definitely improve the pedal feel.

I agree with all of JOEL.WAHLSTEN@domain.elided's comments in v09.n574.

Curt Ingraham
'72 2002tii
Oakland, California

------------------------------