brake bleeding ... 87 5KTQ

[Peter Golledge]

I recall that you have to "block" the prop valve open to get a proper bleed.

With the car up on jackstands the prop valve limits flow to the rear and interferes with bleeding.


On 11/21/2010 4:49 PM, Dave C wrote:
> Howdy Q-heads,
>
> The car is a 1987 5ktq.  I overhauled the brakes, replaced or rebuilt all
> four calipers, replaced the proportioning valve and all the hard lines
> rearward of the engine compartment.  The proportioning valve lever was
> seized due to heavy rust.
>
> Now the brake pedal is>very<  soft and goes to the floor, which I assume
> means there is still air in the system.  I've already pumped about 2 liters
> of fluid through the system, but obviously didn't do a proper job of it.
> I'm not getting any bubbles at the calipers, just fluid.
>
> I'm>trying<  to pressure bleed, but my home made setup doesn't work very
> well.  It's a garden sprayer tank with a schraeder valve and a hose
> connected to a brake fluid reservoir cap.  The cap seal doesn't hold much
> pressure and fluid tends to leak out around the cap and dribble all over the
> place at anything over about 5 PSI.  But this setup has worked in the past
> for ordinary fluid flushing.
>
> I'm wondering if there is something special I need to do related to the fact
> that I replaced the hard lines.  Should the usual method work in this
> situation?  Maybe I need to crack the lines open at some mid point to let
> the air out?
>
> BTW ... the reason I replaced the hard lines is that they looked corroded
> with rusty fuzz on the surface.  After removing the old lines I found they
> seemed to be fairly solid, and maybe didn't need replacement.  On the
> surface they looked like the fuel lines I recently replaced.  The fuel lines
> actually were leaking under the rubber grommets.  When I removed the old
> fuel lines they fell apart, which led me to suspect the brake lines might be
> next.
>
> Anyway ... All I can think to do is try flushing more fluid through the
> system in hopes of getting a solid pedal.  But it seems like I'm doing
> something wrong.  Do I need a better pressure bleeder?  Should I abandon the
> pressure bleeder and try one of those $5 one-man bleeder hoses?  Any other
> ideas?
>
> Dave C
> Columbus, OH
>
>
>
>
>   ... bad on the outsided
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