Re: Bleeding Brakes/Brakeless in Sydney

[David Boxall <hogrider@domain.elided>]

Some of you may remember my post a week or so ago relating to a similar problem
that I had with bleeding the brake system on my '69 Spider.  My brakes were always
very hard to operate, but with sufficient pedal pressure they would pull up the car
in a straight line OK.  The stripped down both brake boosters and they were in fact
both stuffed.  I weighed up the relative merits of rebuilding the Bonaldi boosters
versus replacing them with new, and opted for new ones which were supplied by
Highwood in UK.  Fitted them with no problem and set about bleeding the system.  I
should perhaps mention at this stage that a fair time, several months elapsed
between fitting the boosters and bleeding the system whilst waiting for "her
indoors" to provide the extra pair of hands, or feet in this case.  Pulled through
copious amounts of fluid bleeding in the same sequence as Dave from Sydney, but
couldn't clear the air completely.  Bought myself one of those single handed pumps
but no improvement.  After my posting on the digest I received many messages of
helpful tips, and I would like to thank you all here and now, but as it turns out
the one that did the trick was the bleed nipple on the master cylinder.  Bleeding
the air trapped in there did the job. Now I have fantastic brakes, powerful,
progressive, just as I always believed an Alfa should be.  My only bit of advice to
offer Dave is to replace/rebuild master cylinder if he is sure that there are no
other leaks in the system.

David Boxall
'69 Spider, Dubai, UAE, where the daytime temp now is a beautiful 80 degF, and yes
you bet I am driving the Spider regularly, if not daily.

>
> Finally got my new '75 spider home a week ago,
> bit of a drama driving it around Sydney as it
> had no useful brakes.  Didn't notice on the (very
> brief) test drive that they were so bad...
> (Details - 1975 Spider Veloce, Australian
> delivered (Euro spec I suppose), RHD).
> This is one of the models with 2 vacuum
> boosters and a master cylinder under the
> floor.  Symptoms:  The pedal was hard and
> very low.  Pumping the pedal didn't bring it
> back up.  The car did brake eventually but
> pulled to the left.  Scary.
>
> Anyway, The vacuum hoses to the boosters were
> cracked/leaking so I replaced them.  This
> encouraged brake fluid to come out into the vacuum
> hoses from the stuffed boosters.
>
> I pulled the (Benditalia) boosters and had
> them sleeved/kitted and re-installed them.
> Bought 2 bottles of brake fluid and bled out
> the disgustingly dirty fluid from
> the system.  Boosters hissed properly
> when the engine was started, so they look
> like they're holding vacuum.
>
> I then bled the brakes, starting at the right rear,
> left rear, right front, left front.  Pulled out
> copious amounts of dirt, 2 different colours of
> fluid and a lot of air from the installation
> of the new boosters.  Didn't stop bleeding each
> corner until a nice even flow of new fluid
> minus bubbles came out.
>
> Made sure nothing was leaking, then test drove it.
>
> Now, much better brakes (stops in a straight line)
> but pedal travel is still long and can be pushed
> directly to the floor if enough force is supplied.
>
> I then noticed the brake bleeder on the master
> cylinder today.  I bled that (a nice big burp of
> air, dirt and old fluid came out).  The brakes
> now engage much earlier but the pedal still feels
> awfully soft.
>
> I think the master cylinder might be stuffed but
> then again I don't know whether there is a special
> trick to bleeding the brakes.  Anybody know?
>
> Sorry about the long post!
>
> dave.
> brakeless in Sydney.
>

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