There is an o-ring on each end of the PDWA piston that is
supposed to prevent brake fluid from leaking into the center of the PDWA
assembly. The warning switch should never see any brake fluid, so if you
are seeing a leak there, the o-rings are bad, not the switch.
The PDWA is easily rebuilt however, so not to worry.
Remove the PDWA from the car. Clamp it in a vise with some wood
blocks, and use a wrench to remove the end plug. By thumping the PDWA
against a block of wood, you should be able to dislodge the piston and
it should pop out of the housing. You may need to lever a small
screwdriver against the piston through the switch hole to dislodge it.
It will come out, so be patient. You may find that you can use a dental
pick to pull the piston out, or if you have compressed air you can blow
it out of the housing.
You will need to replace the 2 o-rings on the piston, and I
recommend that you also fit a fresh copper washer before you reassemble.
Lubricate everything with brake fluid prior to assembly.
I picked up the o-rings and washer at my local hardware store.
The o-rings are 2mm x 8mm (metric) viton as I recall. I don't remember
the size of the copper washer, but I just went through the drawers until
I found a matching size (it was a tad thicker than the original, but
otherwise identical). Total cost, $1.50 in parts.
'Course, you will need to bleed your brakes when you are done.
And do NOT let that brake fluid sit on your paint!!!
Now would be a good time to consider switching to silicone brake
From: firstname.lastname@example.org [mailto:email@example.com] On
Behalf Of Greg Perry
Sent: August 05, 2005 9:58 AM
Subject: PDWA warning switch leak
My PDWA warning switch is leaking (overflows) brake fluid from inside
the the female connector over time. Since there is not an o-ring or
gasket on the switch or the mating surface of the PDWA valve, is the
space between the switch and the internal piston of the PDWA valve
supposed to be full of brake fluid? Basically do I need to rebuild the
PDWA valve or just replace the warning switch?