Hey guys, got an issue - I'll explain best I can - proportioning valve is working as supposed to...problem is, when the brakes are applied, I have a leak - it's the hex piece that the rear brake line bolts into. There is a little rubber cap that brake fluid oozes past and drips from. I took it off tonight and the cap simply lifted out of the hole with a knife point. Was this originally glued in, or what? What is the purpose of that piece, with the side orifice and all? There appears to be a spring inside and I'm assuming that is compressed upon the piece being screwed into the back of the proportioning valve. I want to epoxy the edges of the rubber piece and put it back in but am not entirely certain there should be fluid at that opening in the first place or if that is an indication of a problem. Any help? Thanks

 

I am not sure what you are talking about on the valve itself, but I can assure you that little rubber piece will not hold any fluid from leaking out. It sounds like it keeps dirt from getting in. In a panic stop you can have a couple thousand psi on the brake system.

 

A little, rubber cap? See if you can identify it in this thread:

https://www.ford-trucks.com/forums/1...lve-issue.html

 

For a moment there, I thought I had an answer...but they went another way there. The part that is leaking on mine is the brass piece that bolts into the valve and the rear brake line bolts into that. That dude locked up the main shuttle in the valve, this issue is further back from that. I have fluid flow at all 4 corners, as I just bled the brakes. I'm not sure what this piece does or why there's fluid at that rubber piece...

 

Here's a picture of one type of valve. In this picture it looks like the threads and the seat that seals are made into the valve. That piece you are talking about might be a adapter. If it is, it probably has a female taper that seats against the male taper in the valve body. The only other way it could seal would be a o-ring trapped up in the body.

 

http://images.cjponyparts.com/media/catalog/product/cache/1/thumbnail/9df78eab33525d08d6e5fb8d27136e95/b/c/bcv1_2.5.jpg

In this picture, look all the way to the left at the adapter coming in..with a black circle right before the main block body. That black circle is the rubber piece that is being oozed around

 

Not sure what that is. We need a drawing of that type of valve. They made so many types of these things, it's hard to figure it out sometimes.

 

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