Brake pedal goes to floor

[SJ]

> From: "John Larson" <j.d.larson at verizon.net>
> Subject: Re: Brake pedal goes to floor
>
>
> "Does the master cylinder fail is such a sudden way?
> My parts guy says a new one is about $150. No rebuild kits for this.
> P/N is 893 611 021 . . both brake lines are on Port side . . bleeder valve
> on end."  SJ
>
> Bleeder valve on the end?  What bleeder valve?  Brake lines on Port side"?
> They're on both sides in the picture on the Worldpac site.

**** Port side = nautical term = drivers side . . . . more concise than
saying right side.
Yes, the master cylinder actually has 2 brake bleeder valves . . each
directly opposite where the brake lines get screwed in.
Nifty, maybe for bleeding air out . . kinda like a top air bleed(temp
sensor) in the water cooling system.
Yes, both brake lines are attached on same side(Port) of Master Cylinder.

 Yes, they DO
> fail like that, $150 is a VERY good price (since dealer list is $404), and
> my shop cost is $178.85.  Be aware there are THREE different master
> cylinders (depending on how your car is equipped), and you need to be sure
> you get the right one.

**** My parts guy is friendly to me, I install the FA on his computer. :-)
My 88 5kq uses the MC that you describe . . .a brake line on each side. . .
443 611 021.
The 90 100q uses this odd MC . . . .  893 611 021. The FA picture shows it
correctly.
The third version must be the non ABS type.

What is the failure mode for the sudden collapse of  the MC?


SJ
85 Dodge PU, D-250, 318, auto
85 Audi 4k - - sold but still on the road
88 Audi 5kq
90 Audi 100q