• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

Bleeding brakes after cadillac caliper install

Marvelous3

Who engineered this?
Joined
Nov 12, 2002
Location
Atlanta
I know I'm a dumb ass but I'm having a very difficult time bleeding the brakes after installing these cadillac calipers up front and reman'd Volvo calipers in the rear. I've done the bleeding procedure about four times now and still have a pedal that sinks all the way to the floor so what am I doing wrong?

I've got a power bleeder pushing fluid into the master cylinder. I go to the right rear and open the bleeder screw. Let it do it's thing. Close it once the fluid runs bubble free then move on to the left rear. Repeat process. Then onto the front right and finally to the front left. Unscrew my power bleeder, reattach the master cylinder cap, and I've got a pedal that goes to the floor. I know I might have to bleed them a couple times after removing everything and installing new but this is kind of ridiculous. So what am I doing wrong?

Brake set up:
New '94 ford mustang gt master cylinder per mopar's advice.
cadillac calipers up front
beck arnley reman's in the rear.
new braided lines on all four corners.

I don't see any fluid leaking and my bleeder tests out to hold 15psi no problem. Maybe I need to pump the power bleeder up to more pressure? Been keeping it between 10 and 20 psi.
 
Well so I held it in my hand, filled it with fluid, then pumped it with an extension. Added some more fluid. Stopped pumping when I didn't see any more bubbles. That counts as bench bleeding right?
 
Well so I held it in my hand, filled it with fluid, then pumped it with an extension. Added some more fluid. Stopped pumping when I didn't see any more bubbles. That counts as bench bleeding right?

It does. Try getting a helper and do it the old fashion way. Pump it up, hold, bleed.
 
Try lifting the back of the car. A local had air trapped in the proportioning valves (atleast his guess) and once the back was high they bled quickly.
 
Try lifting the back of the car. A local had air trapped in the proportioning valves (atleast his guess) and once the back was high they bled quickly.

^ This and or tap on the proportioning valves with the handle of a screwdriver while you bleed them to break up the bubbles.

Also after having the system open I always abandon the official order initially, and bleed the top fronts first, [air rises] and then the fronts so as to NOT send any air out back to be trapped in the proportioning valves.

& INB4 defective rebuilt calipers...

:-P
 
^ This and or tap on the proportioning valves with the handle of a screwdriver while you bleed them to break up the bubbles.

Also after having the system open I always abandon the official order initially, and bleed the top fronts first, [air rises] and then the fronts so as to NOT send any air out back to be trapped in the proportioning valves.

& INB4 defective rebuilt calipers...

:-P

I could try unbolting the portioning valves from the under body and see if I can get them to hang such that they're the lowest part of the system.

You all think I've maybe just got giant air bubbles in the portioning valves? Even with the power bleeder forcing fluid into the system?
 
Major mismatch between mc and caliper volume? That happened to me a long time ago on a VW, the calipers, hmm, or was it the slaves/rear, were too big.
 
Major mismatch between mc and caliper volume? That happened to me a long time ago on a VW, the calipers, hmm, or was it the slaves/rear, were too big.

Nope, even with the stock master cylinder the pedal won't go to the floor. With the larger master cylinder the pedal is factory feel.

Try gravity bleeding everything, starting with the rears.

Make sure the calipers aren't upside down (bleeders should be at the top)
 
Initially I had the rear calipers on with the bleeders on the bottom. I swapped them around last night so the bleeders are up top but same result.
 
Something I ran into the first time I swapped on bigger calipers on a motorcycle was the fact that master cylinder was now too small. And it makes sense too. I went from 2 piston floating calipers to much larger 4 piston Nissens. I upgraded the master to a unit from a CBR600RR and all was right in the braking world!

The point being that maybe the master is too small? Are others running these with the OE master?
 
Major mismatch between mc and caliper volume? That happened to me a long time ago on a VW, the calipers, hmm, or was it the slaves/rear, were too big.

Immediately my thought as well.

Nope, even with the stock master cylinder the pedal won't go to the floor. With the larger master cylinder the pedal is factory feel.

You mentioned OE and a larger master. Which is the OP using?
 
I sometimes use a combination of gravity bleeding, pressure bleeding, vacuum bleeding, and then if I can get a man to sit in the driver seat for a minute; pedal bleeding is usually the most effective and comes last after I have at least tried some of the other methods as a preliminary bleed.

One of my favorite bleed methods at home includes a bicycle inner tube and a bike pump. Any idea how I do it!?
 
Back
Top