disc conversion caliper lock up

[73dreambronco]

I have the horsepowersales(ebay company) front disc conversion on my 73 the calipers close but then lock up, I pushed the plunger in the caliper back together with a c clamp and it moves freely, but as soon as i pump the pedal it locks up and i cant turn the hub(even with a crowbar) I can turn them with the tire on but its very tight. the kit came with everything new, spindles, backing plate, hubs, pads, all new lines,underhood proportioning valve ect

what do you guys think?

 

[Bully Bob]

Hi '73....

Check the stroke on the master cyl., If it isn't coming all the way back, it will hold pressure.

--Adjust--

-OR- you may have rec'd a faulty proportioning valve.

 

[Seabronc]

Call the guys you bought it from. They may have had the problem before.

Good luck,

>-

 

[bigbluebronc]

MAybe it got plumbed backwards somewhere?

BBB

 

[69bronc347]

your vehicle came from the factory with drum brake which use a residual check valve that hold about 10 lbs of pressure so the springs in the brakes dont push the fluid back into the master cylinder, which would hold the brakes on if you switched to disc brakes, what you need to do is get a proporting valve for disc brakes, because the check valve is built into the proporting valve, that will take care of your problem

 

[69bronc347]

oh sorry, i didnt read the end of your post, you already put the valve in, either they gave the wrong one, you mixed up the lines from front to rear, or the valve is bad