Re: brake safety switch (proportioning valve)

["Jim Blair" <carnuck@xxxxxxxxxxx>]

A: Since it's not a real prop valve, I would switch it for one from a disc 
brake system, or get an aftermarket adjustable one from Summit ($35 average 
on Evilbay) The common Jeep fix is to take the o ringins off and lube the 
piston lightly with PBR rubber grease (available mostly in Brit car 
enthusiasts shops) as it is the ONLY assembly lube I know of that is 
compatible with brake components. If there is another, I'd like to hear 
about it. I'm about to dive into modifying the brake system in my Comanche 
because the load level sensor makes it brake erratically since my 6" lift 
and 33" tires.


From: "Armand Eshleman" <aje1@xxxxxxxxxxxxxxx>
To: <mail@xxxxxxxxxxxx>
Subject: brake safety switch (proportioning valve)
Date: Sat, 28 May 2005 18:47:46 -0500

Well, I don't think it's a proportioning valve anyway. It's on my 1970
Javelin.
It had power drum brakes all around. I am putting bendix calipers, and the
other
disc parts from a 75 Hornet on the Javelin.  Anyway I'm dismantling the
entire brake
system and cleaning and replacing things. So I pull all the brake lines off
the "valve"
(actually it looks like a safety switch only, the "piston" inside can only
move toward the
side of the failure to allow the spring loaded switch to become energized
and illuminate the
brake warning light. Now I know why it hasn't done that after a couple of
master cylinder failures.
The piston was cobbled up with debris and was stuck. Anyway as I was taking
it apart and cleaning
I noticed this yellowish looking stuff inside that appears to be the
remnants of some sort of assembly
lube. It was packed into the area towards the center of the two little
piston pieces that have o-rings on
them. What is this stuff and what should I reassemble this thing with? Maybe
regular brake fluid would be
OK for an assembly lube, anyone have any good ideas? Oh yeah almost forgot,
one o-ring has two flat
spots on it so I have to replace that, I will try the local Ace Hardware
store, they usually carry a very good variety
 of o-rings, or ? if I can't find them there any other place you guys have
found these tiny little buggers? They
are about 3/8" od and about 1/16" thick, don't know the id, I'm afraid to
remove them until I find a replacement.
How many other brave souls have disassembled one of this with any success? I
hope I'm successful.................


Armand