Prportional valve

[charger freak2]

I have been playing with the brakes on this car for way too long and now i'm finally ready for the road, to get it at least inspected. I replaced all brake lines, calipers, master,proportional valve and bled everything and when I pump the brakes up , the front calipers stay pressurized from the proportional valve to the calipers. with no pressure on the in port on the prop. valve.   The brakes work fine if you just feather the pedal to stop, but if you push a little too much they lock up.  Any adjustment to these   1973 Charger

[Musicman]

Actually... the proportioning valve is part of the rear brake system... the valve in your photo is actually a combination valve and has 3 parts to it... a proportioning valve, a hydraulic safety switch, and a hold-off metering valve. Did you say that you have replaced this valve already? I ask, because there is a small low pressure check valve within the metering valve that allows residual break pressure to bleed back to the master cylinder after breaking. However, it seems to me that if it were sticking, it would be sticking all the time and not just during hard breaking, but you never know. It would also be highly unusual for this valve to fail, but again you never know. Normally the metering valve itself fails open or shut due to corrosion of it's bleed stem caused by exposure to the elements, but the symptoms of this are quite obvious, and not the one that you have described.

[charger freak2]

i think maybe they gave me a 10 lb. residual, switch instead of a 2 lb. switch,     which I think maybe a 10 lb. switch would be used for drum, or maybe I'm backwards, anyway I think i'll put the original one back on and see if it cures the problem, I just figured I'd change it while I was changing everything else........

[Musicman]

You are correct... a 10 lb valve is used in the rear brake system... a 2 lb valve (optional, only if master cylinder is located lower than the brake caliper) is used in the front. You shouldn't need any type of residual valve in your front disc system, only the rear drums, but I thought we covered that ground already in another post.

[Chatt69chgr]

There is an excellent tutorial on these on the Pirate Jacks website.  They are the retail part of MBM Brakes out of Asheville, NC.

[charger freak2]

Thats where I bought it

[Musicman]

You can test the metering valve asembly easy enough... just because it's new, doesn't mean it isn't broke. I'm headed out the door at the moment, but I can repost with a test procedure for you later if you wish, just let me know and I'll post sometime later today.

Mike

[chargerman68]

There is an excellent tutorial on these on the Pirate Jacks website.  They are the retail part of MBM Brakes out of Asheville, NC.

does this place do brake caliper rebuilts...have a buddy with a dart

[charger freak2]

I put my original valve back on and I have no more problems...... with the brakes anyway.....I just wanted to change it cause I was changing everything else.......The one that pirate jacks(MBM Brakes) told me would work was either the wrong one or just didn't work.

[Musicman]

I put my original valve back on and I have no more problems...... with the brakes anyway.....I just wanted to change it cause I was changing everything else.......The one that pirate jacks(MBM Brakes) told me would work was either the wrong one or just didn't work.

Not really surprised, as I said... sounded like the unit you had in there, had a faulty check valve in the metering valve portion of the assembly.

[charger freak2]

Look on www.piratejacks.net