re. Leaking brake pressure regulator in '87 4kq

[Ben Swann]

Luis,

I agree with the sentiment most folks would say about replacing the regulator, especially since this is a saftey item, but since that was not the question you asked and understanding your predicament, here is something for you to try.  This is at best a stopgap measure until you can afford and install a new or used good regulator.  Come on folks ease up on having to follow every nuance of replacing parts properly - not everyone does and sometimes a workaround is apropriate for the situation.

Here is what I did  on one of my 4kq's  and it worked fine for quite a while: 

Clean the front of the regulator where the leak is occurring - a spray carburator cleaner will break down the residual fluid to provide a clean surface.  Once you have it as clean as possible, apply some black silicone sealant to make an external gasket.  Let it cure for some hours.  Then fill the reservior with fluid and bleed the brakes as appropriate - you will need to bleed the regulator as well as the ports on the MC.  Check that this actually has stopped the leak by having someone apply the brakes.

This worked good for me as the leak was tending to suck air in rather than push fluid out.  With the silicone in front, the gasket made a good seal without having to tear things apart.  Then just be vigilant about checking your fluid regularly until a replacement is done.  If you are lucky like I was, the seal may hold for some time, in my case over a year.

Now for the folks who suggested the regulator is cheap, please advise us as to where to get one.  I checked several FLAPS in my area and it is unobtanium.  Dealer price is outrageaous.  I'd be open to information on a rebuild kit if applicable, but really would prefer to just install a good one if it can be found for not too much $$$.

Ben

[Date: Fri, 30 Jul 2004 00:38:46 -0700
From: " Luis Felipe Pati?o " <lpatino at nethere.com>
Subject: Leaking brake pressure regulator in '87 4kq
To: <quattro at audifans.com>
Message-ID: <000901c47608$3f9ebc80$f8813f42 at mypc>
Content-Type: text/plain; charset="iso-8859-1"

Dear Audifans:

my 4kq's brake pressure regulator is leaking about 500 mL of brake fluid every 3 days. I keep it topped off, never even letting it get to the 'min' mark. The fluid leaks from the depression in the cylindrical bulge that has that depression with something that looks like a hex bolt head sticking out of it.

Can this leak be stopped _safely_?

Although I searched the archives to see if these leaks could be fixed, all the articles merely said to replace the brake pressure regulator because "it's cheap."

Well, to me it isn't: I am in such serious financial straits right now that even $10 mean whether I eat or not that day. Still, I must keep my great q braking safely.

OTOH, maybe a kind fellow audi lover could send a good used brake pressure regulator my way...

Thank you all, your help is very much appreciated,

Luis Felipe Patino

PS please email me directly, too, since I get the digest version of the list.]