97 rear discs not working

[chuzie]

I pulled the rear discs from my parted 97 Explorer and put them on my Bronco. The axle is a 74 so it was a direct bolt on.

My rear discs are not stopping the tires even from a leisurely roll when raised from the ground. They are 35" tires with beadlocks so I know they weigh a lot but I should get some braking especially with weight off wheels.

I am not extremely familiar with troubleshooting Explorer disc brakes but they seem pretty simple like most disc brakes. Hopefully someone can help me figure this out.

As of now, my front discs work great so I switched the front and rear lines around on the master cylinder to eliminate my MC/booster as a factor: no brakes

I removed my proportioning valve so it is a straight shot to the rears: no brakes

Installed brand new pads- no brakes

I know I am getting fluid to the rear calipers since I was able to bleed them. There is ZERO air in this system so PLEASE don't try and tell me otherwise.

I know the calipers are not seized because I watched the pads close when pumped with the caliper unmounted.

There is no weird valving in the rear lines on our Explorers, right? I ask because I am using the Explorer soft lines integrated with my main line due to the big lift and the need to reuse the fittings that go to the calipers.

Now the pics below show the calipers upside down and I have since fixed that.

Here is what I did...

I took the Explorer soft line setup and capped the port on the splitter that had the hardline output and connected the integrated soft output on the splitter to the right caliper.

I ran the soft input line of the explorer splitter to the right side of my Bronco splitter via hardline. It ain't pretty but my flaring tool broke so I am stuck with this for now.

The left side of my splitter connects to the left caliper soft line via the ugly hardline.

Here is my left side setup.

Please help a brother out.
Thanks!

 

[koda2000]

i'm assuming a '74 had drums on the rear to begin with. did you also swap out the master cylinder from the Explorer? disk brakes require a different master cylinder than one for drum rears, and probably a different proportioning valve too.

BTW, I can't see your pictures. you have to use a link to something like photobucket.

 

[chuzie]

Yes and Yes. Swapped drums for discs and swapped the old MC for a vette style disc/disc MC from CCA. I really was hoping to have just received a bad MC but switching the front and rear lines on the MC should have solved my issue if the MC was bad.

 

[koda2000]

Yes and Yes. Swapped drums for discs and swapped the old MC for a vette style disc/disc MC from CCA. I really was hoping to have just received a bad MC but switching the front and rear lines on the MC should have solved my issue if the MC was bad.

weird. maybe the lines going to the rear have blockage (rust or crud buildup inside, kinda like cholesterol). I've installed quite a few brake systems (drum/drum, disc/drum and disc/disc) and have never run into this problem. of course, I've always used new lines and residual valves where necessary (you shouldn't need residual valves for your app). the only problem I've ever had was having the rears lockup before the fronts (on a pickup) and an adjustable proportioning valve solved that problem.

 

[chuzie]

Agreed. I have all new lines from the MC to the rear axle so the only thing even semi-old are the Explorer soft lines I reused. I am going to pull the lines and take a look. The folks at CCA want me to pinch off the soft lines to see if it changes my pedal. Thanks again.

 

[chuzie]

Ready for a stupid question?

The fitting (block) at the caliper end of the Explorer soft line has a recess on one side and is flat on the other. I ASSUME this recess goes toward the bolt head, correct? Looking at it, I would imagine it will not seal the copper washer if the recess were against the caliper, correct?

The only reason I ask is if I have it wrong, the bolt would not be positioned correctly in the caliper.

I am shooting in the dark. Still have to pull the lines to check for blockage but I haven't been home yet.