Brakes bringing project to a screeching halt..

[PappyJoe]

I have converted to 4 wheel disks. Having troible getting them to work. At this point I'm really looking for a recommendation on someone to talk to or take it to in the Ft Worth Tx or Weatherford Tx area. Recommendations would be much appreciated. Thanks

 

[Ironbuilt]

What problems are you having? A little description will help others help you.

 

[PappyJoe]

No pressure. I have installed simple two piston systems front and back. Nothing complicated. I used ssbc booster, master, and proportionate valve. I have bench bled the master. I have power bled the whole system. No leaks, no air in system. I have tried it with the engine vacuum to the booster. I have tried it with the SSBC vacuum pump to the booster. I have tried two different brackets on the booster mount to firewall for linkage clearance. I put a gauge on the outputs of the proportionate valve and on the output of the master. Small blip on the gauge is all I get when I press the pedal. I know it's not rocket science and I've worked on much more complicated hydraulic systems. But I'm at a loss. I have ordered and recieved a new booster/master/proportionate valve setup from classic industries but I'd really like to get another set of eyes on this before I install it. Once I install I can't return it.

 

[Don Frelier]

I would suggest go back to the beginning. If you have or can find the plugs for bench bleeding the master take off the lines and put them on the master. Or make some blanking plugs to replace the lines (solder some fittings shut). See if you get a hard brake pedal.
Then go from there.
This may sound obvious and silly, but are the bleeder screws on the calipers at the highest point?
Otherwise you can never get the air out of the calipers.
I hope you get it figured out, I had similar problems on a daily driver once... long time ago it was really stressful.

 

[747mopar]

How does the pedal feel, are you getting a stiff pedal at all? Are all of your bleeders facing up on the calipers, if not you'll never get the air out. If I had to guess I'd think your not getting enough stroke?

 

[PappyJoe]

The Pedal is firm. The bleeders on each are up. Stroke is the reason for the different brackets. I know I'm getting enough stroke to have at least some pressure.

 

[2quick]

Had a problem getting a pedal on my Wilwood setup. Bleed everything multiple times almost gave up when my buddy told me to bench bleed the master 1 last time, so we did for a bout 10 min and finally we had a burp of air come up, Put it back together and all better. So moral of the story if you don't see any leaks it very well could be air bound somewhere. Probably the master if your getting nothing. Just keep bleeding!

 

[BIGSHCLUNK]

pp valve defective?

 

[funknut]

If you put a pressure gauge on the MC and don't get any pressure then I would fix that before going any further down the circuit. The suggestion to troubleshoot the master cylinder sounds like the best first thing to do.

 

[BeepBeepRR]

I had this problem with a rightstuff master.. No matter how much i bled the master I could not get it to get pressure. Ended up having to get a new master from Summit.

 

[PappyJoe]

I'll give the new system a good checkout tomorrow. If the linkage looks like it'll work I'll bite the bullet and give it a shot. That will replace all of the possibilities in one shot. Just not sure the linkage matches up at this point.

 

[ckessel]

See if the pushrod from the booster is engaging the master properly. I did a master on an AMC Scrambler that the car owner provided. Looked the same but had an issue locking the brakes up. Cracked the cylinder fittings open, had pressure built up with it just sitting there. Hmmm. Measured the rod stickout of the booster, measured the back bore of the master where the rod goes, compared that to the old master. Bingo! Hole was not as deep. Backed rod off, end of discussion.

 

[5.7 hemi]

What size mc? With 4 wheel power disc you should use an 1.125 bore size mc.

 

[biomedtechguy]

What size mc? With 4 wheel power disc you should use an 1.125 bore size mc.

For what it's worth, I just had a 4 wheel power drum brake system replaced with a 4 wheel power disc Wilwood system, 11" rear discs, 12.19" front discs, 2 piston calipers all around, switched out the factory 9" booster for an 8" booster and used the 1" bore diameter Wilwood master cylinder. Vacuum at idle is at least 16 and the brakes work great! I was hoping for a little more effort and pedal travel, but the difference is minimal and I wouldn't change anything, especially not making them any more powerful or "easier" to engage.
My .02

 

[PappyJoe]

Update. The linkage did match up. Still had a problem that the had sold me and I mounted two left brake calipers on the front. Got the correct one and bled. Now I do have brakes. Not good enough yet but they work. Now I need to see if I'm going to need to run a vacuum pump.