what is this on my proportioning valve

[no_rice]

so i put power disc/drum mastercylinder proportioning valve and booster on my truck recently.

my lines and everything else are holing just fine with no seeping/leaks it seems, but this part of the valve seems to be seeping a little...

there is a hex head on it but it sure looks to be a molded part of the valve body. before taking the pic, and before i could see it very good since its on the bottom, i put a wrench on it and couldn't budge it. even if i could, it appears to be coming from the hole in the center...

i guess the more appropriate question, is how do i stop it from seeping?

[cableguy0]

If im looking at your picture correctly there should be a button sticking out of that hole. The actual valve part of the proportioning valve should be sticking out of there. If its leaking you likely will need a new valve.

[cableguy0]

Also just as a side note. PLEASE remove those POS compression unions and flare the line and use a proper union. Compression unions should not be used in brake lines.

[69chevytrucker]

thats my guess to kinda like when a water pump weeps its done

[undertaker72]

in the state of Utah those compression fittings (union) do not even pass state vehicle inspection , sometimes it can be like stepping on grapes , you never know when your going to be wineing

[dwcsr]

your missing parts on that valve

[PGSigns]

I think it is time for a new valve and some new lines. You have to get those compression fittings out of there.
Jimmy

[no_rice]

hmm, looks like there should be a cap or something there on the new one pictured atleast. the hole sure seems to be just a sealed recess in the bottom though. cant seem to find how anything would go on there. i messed with that with a small pic and screw driver last night, and couldnt seem to find anything in there that may move or leak. seems capped

as for the compression fitting. i suppose everyone has there opinion just like plugging tires.

ive used them more times then i can count on cars ive run for ALOT of years and miles. plenty of full bore 2 foot braking to avoid deer and such, and never once run into a problem. could something happen, sure. something can always happen. ive had enough old brake lines without without any compression fittings blow under emergency stop situations. had wheel cylinders blow. IF that line was to let go, would i lose my brakes. not especially. the front discs would still be doing their job.

[cableguy0]

Compression fittings being bad in brake lines aren't an opinion. It is a safety issue. Brakes are sort of important and I personally would prefer that other vehicles that might be on the highway near me were PROPER and safe. Compression unions wont pass inspection in most states. It has nothing to do with anyones opinion they are fine in low pressure situations but have no business in brake lines.

[PGSigns]

If you had a steel high pressure compression fitting on there like a Swagelok designed for a steel tube thats one thing. You have a brass one rated for a max of 500 psi and not recommended for steel tube by any of the manufactures on your brakes. There is a reason they are not allowed most states. You may have had luck with them in the past but what happens when your luck runs out.
Jimmy