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Old 10-06-2013, 04:29 PM   #1
namkyoo98
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what is this part???

My proportioning valve leaks from the top. I was told that the part on top is the brake pressure switch. Is this correct? My auto parts store has given me the wrong part 2 times if it is.
I put new brake hoses,lines and new calipers on my truck but when I went to bleed the brakes its leaking!getting frustrated and dont know what to do next. Any help is much appreciatted. Also where can I buy this part?
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Old 10-06-2013, 04:50 PM   #2
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Re: what is this part???

Prop valves rarely wear out, it might be easier to hit up the wrecking yard and find a whole nother unit.
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Old 10-06-2013, 06:29 PM   #3
namkyoo98
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Re: what is this part???

Thanks woodwright. I know that it's the proportioning valve but I was talking about the part on top of it that has a wire coming from it. After researching I found that it's called the Proportioning valve switch connector. Is it possible for brake fluid to come out of that? I'm at a loss because I highly doubt the valve is cracked. Fluid was shooting out of it when I tried bleeding the brakes. Very confusing. I am itching to bleed the brakes and check out the new brakes!
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Old 10-06-2013, 06:32 PM   #4
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Re: what is this part???

I mean go pick up the whole unit.
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Old 10-06-2013, 07:27 PM   #5
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Re: what is this part???

I will do that woodwright. I guess I have no other choice
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Old 10-06-2013, 07:44 PM   #6
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Re: what is this part???

Pop the wire clip off and tighten it a hair. Gently!
If that don't fix it pull it off and check for a gasket.
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Old 10-06-2013, 08:07 PM   #7
namkyoo98
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Re: what is this part???

I will try that geezer#99, thanks! I pray it works. So it's possible brake fluid could leak out of it???
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Old 10-06-2013, 08:15 PM   #8
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Re: what is this part???

It could leak. It's not supposed to though. Maybe the seal inside on the piston could be bad. Here's a link to what they look like inside.
http://www.gnttype.org/techarea/brakes/prop.html
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Old 10-06-2013, 09:16 PM   #9
namkyoo98
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Re: what is this part???

I am thinking that plastic piece cracked while I was installing the new brake lines when I unbolted the proportioning valve away from the frame
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Old 10-06-2013, 10:35 PM   #10
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Re: what is this part???

its probably pipe thread. just jam a pipe plug in there. your cluster light probably doesn't work anyways
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Old 10-07-2013, 08:53 PM   #11
namkyoo98
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Re: what is this part???

Well, after looking into it further the leak is coming from the line coming from master cylinder for the front brakes! I must have made it crack while removing the proportioning valve away from the frame. Glad I found the source.
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Old 10-07-2013, 10:45 PM   #12
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Re: what is this part???

I doubt it, the hydraulics are designed to hold thousands of PSI, tightening a tube nut won't cause any cracks other than in the tube if it's not done properly. If you just put new lines on, and now you have a leak, chances are the nut is not tight or cross threaded or stripped and the flare is not seated or is damaged and not sealing. It is also possible that after replacing lines that were leaking you've exposed other leaks in wear parts. It's not uncommon for the seals in wheel cylinders or the master to blow after replacing a hose or line, just because they became the weakest link.
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