brakes wont stop car!

Attachment 53706Attachment 53707this balance bar setup has me stalled. I have the .75 mc to front and .625 to rear. Drove the car first time today and it would barely stop! Stock ffr front and powerstop (stock) rear brakes. Bled both mcs and all calipers many times , no air at all. I need opinion on this goofy balance bar system. I have far to much pedal travel before brakes begin to engage and then the pedal is softer than I have ever felt on other setups. Guys, WHAT AM I DOING WRONG?,!! How do I set up this system so it works? Any help is welcome
tom 916.812.5441
thanks

IMO you must still have air in the lines. Double check that you do not have any leaks. The pedal should be firm. It will take more effort than power brakes but should do the job better than you are communicating.

I'm having the same issue, I removed mc's and bled on bench and vacuum bled all 4 corners. removed balance bar setup and re rigged per wilwood website . I did find that the mc's where to far apart on the bar so I set them per Wilwood but I am still having a soft pedal about 1/2 travel before they firm up. how should the Bias be set.

Quote:

---

Originally Posted by Vladik41

I'm having the same issue, I removed mc's and bled on bench and vacuum bled all 4 corners. removed balance bar setup and re rigged per wilwood website . I did find that the mc's where to far apart on the bar so I set them per Wilwood but I am still having a soft pedal about 1/2 travel before they firm up. how should the Bias be set.

---

You have done exactly what I have done out here. I also looked at Wilwoods site but the actual setup of the balance bar is not clear to this old man. With the pushrods screwed into the clevis as shown in my pictures, I have at least 50% of pedal travel before the master cylinders begin to feel pressure. Wilwood and FFR (surprise) documentation fails to mention how far to screw the pushrods into the clevis for each side so I am just guessing. IMHO, I now think I need to back these pushrods out all the way to allow engagement much sooner. I was hopeful that someone on the site could look at the pictures and see if mine are screwed in to far and offer a little advice as to what to try next. If there is air in the lines, I am at a loss as to how to get rid of it short of having it pressure bled by someone smarter than me. I have done the bleeding using the old one at a time farthest away from MC routine and I have tried doing RR and RF at same time followed by LF and LR and get the same results. Never a single air bubble and the reservoir is kept full throughout the procedure so we have not introduced more air up top.

Can anyone tell me how far out their pushrods are for both front and rear MCs? Also, I assume I should be using .75 MC for front brakes and .625 for rear. Is that correct? Is this picture from Wilwood correct as far as setting up the balance bar?
Attachment 53708
is there an accepted procedure for bleeding this dual MC setup?

If I can send/post anymore clarification I will be happy to do so. Just let me know what is missing so I can get this working and perhaps help some others who struggle with this nonsense.
thanks again

In the 4 Wilwood setups like you have, that I have done I have bleed the brakes using someone pushing the brake pedal down after pumping it up and started at the farthest brake and worked to the closest. I have never had to bench bleed any M/C. I setup the balance bar so it activates the fronts before the rear slightly and then fine adjust it on a road test so that I get front lock up before rear in a panic stop. I am sorry to hear you both having such problems. Since I have not I do not have any more ideas to help you out with. Maybe others can chime in?

I agree with wallace18 that it sounds like there is still air in the lines. I know that's hard to believe after everything you've done, but that's what the symptoms sound like. Or there's the possibility of a bad MC. There was a thread some weeks ago with similar symptoms and after trying everything, it was finally determined one of the MC's was defective and that solved the problem.

Having said that, couple of comments. Looking at your picture, you don't have the balance bar centered. So you're going to get a lot of bias the way it's set up now. I agree the instructions from both FF and Wilwood are somewhat vague. For starters I would adjust the balance bar so there is equal amount of threads showing on each side, not including the lock nut. Second, your comments about backing out the pushrods to make it engage sooner are incorrect. The location of the pushrod on the clevises will adjust pedal height, but assembled properly the MC's will be all the way out against the retaining snap ring (under boot) regardless of where the clevis is located. How soon they start to engage is purely a function of the MC. If they take 1/2 inch or more to start engaging from the stops, something isn't right.

I just bled my Wilwood setup in my current build for hopefully the last time yesterday. I had it all done before, but then one of my reservoirs was leaking so had to replace that and start over a little. I did "bench bleed" the MC's while mounted in the pedal box, although numerous people have said this isn't necessary with the pressure bleeding technique I use. My CNC reservoirs have a pressure cap. With 5-10 lbs of pressure in the reservoir, no pedal pumping. Just go to the respective bleeder and crack it open until no more bubbles. I've used the method for several builds and it's always worked. The Wilwood setup in my current build has an almost immediate hard pedal with total pedal movement of maybe 1-1/4 to 1-1/2 inches. Hasn't been driven yet, but I'm expecting it will be fine.

A couple things you may consider doing.
1) move the M cyl. push rods out so the pedal is as close to the driver as possible. this will help you get all the air out of the system by giving a full length push of fluid.
once bleed correctly adjust the M cyl. rods for correct pedal height.
2)when you fill the remote res. crack the banjo fitting loose on the top of the master cyl. just enough to bleed the air out. remember air will get caught in the high places.
and many people miss this as a bleed point.
3) lower the rear of the car close to the floor ( without tires ) this will put the res. higher than the masters, thus helping to push the column of fluid through.

when looking at the bias bar remember there is a bearing captured on that threaded rod right in the middle.
when you move it left or right the bearing goes with it. So the side showing more threads has the pivot bearing closer to it.
this gives that side more leverage to push the master cyl.
when bleeding front brakes move the bias all the way to the fronts
same fro the backs

I hope these tips help
Later
Mark D

Great input you guys. I will do as you suggest and see if it helps. I am still confused about a couple things:
1. If i never get a hard pedal even after pumping it sounds like air in the lines, right. If I get no bubbles when bleeding I agree that a mc could be leaking past its internals causing very soft pedal. How do I isolate to the bad mc? I'll set the bias bar as Mark says and see if it helps but is there a way to eliminate either front or rear mc when bleeding?
2. Edwardb says make the balance bar threads the same length on both sides. Is that the starting point from which I adjust bias to have fronts lock just prior to rears as wallace18 suggests is best?
thanks guys, I will continue to try and isolate the problem with your help..

B Solmon,

BTW: you've gotten great tips and advice so far. I will tell you what happened with my setup so you will have one real life example that may be similar to your issue. My bias bar was set just the way yours is. I had taken my car to the track for a track day. During that time I pounded on the pedal during the session just before initiating the turns each time. I believe I may have damaged the rear MC (the one on the right). The next day I got in the car to back out of the garage and to my surprise, I had no brakes but I was already going down hill out of the garage. I eventually had to put on the E brake. I had the two 3/4 in MCs on my kit. I replaced it with a 7/8 in as advised from the threads about upgraded Wilwood kits. Before replacing the rear MC, I tried bleeding and extending the MC rods to no avail. I just could not get it to bleed even to the point of getting any usable pedal. Finally, I changed it out. I also contacted Wilwood technical and here is what they said. Don't use the balance bar to induce bias in your system. Balance it so each MC is getting the same pressure. They advised that I size the MCs correctly and use a proportioning valve if needed. I already had one installed on the rear line. So when I installed mine, I bled the brakes as normally without any difficulty. Long story short, it must have been the rear MC as I did not change any other components and only evened up the balance bar like several have mentioned here. Now I have just about 1.5 turns on the proportioning valve and it works pretty well. I think I still need some more aggressive brake pads to make them more effective but that's a different thread.

Hope this helps,

WEK.

Quote:

---

Originally Posted by Brave Salmon

Great input you guys. I will do as you suggest and see if it helps. I am still confused about a couple things:
1. If i never get a hard pedal even after pumping it sounds like air in the lines, right. If I get no bubbles when bleeding I agree that a mc could be leaking past its internals causing very soft pedal. How do I isolate to the bad mc? I'll set the bias bar as Mark says and see if it helps but is there a way to eliminate either front or rear mc when bleeding?
2. Edwardb says make the balance bar threads the same length on both sides. Is that the starting point from which I adjust bias to have fronts lock just prior to rears as wallace18 suggests is best?
thanks guys, I will continue to try and isolate the problem with your help..

---

1. Adjusting the balance bar bias toward the end of the car being bled, as suggested by Mark, should help to isolate a defective MC. Hadn't heard of doing that before for bleeding, but it's an interesting idea. Makes sure the MC on that side gets the full stroke for bleeding.

2. I suggested it because it stood out from your pictures how far off center you had the MC's adjusted. At the center is the starting location, and then adjust the bias based on driving. As I recall, that's what the instructions say.

The wilwood rep at the HB show said that power bleeders should not be used when bleeding the brakes with their master cylinders. He recommended the traditional method that Wallace outlined.

Even though their website says power and vacuum bleeders can be used.

https://www.wilwood.com/m/techtip/Te...spx?id=10&no=1

Has anyone figured out how to isolate the mcs? Can i block the rod on one to prevent its movement and then bleed to other and check for a hard pedal?

isolating the master cyl. is not needed
If you want to see which end has the air in just watch the rods move when someone pushes on the pedal
they should move pretty much the same amount. not a huge difference.

If you push on the pedal and 1 cyl. moves alot and the other slightly. then you know that the one that moves alot has the air.
If you push on the pedal and they both go to the floor , or close to it then they both have air.
it really is that simple.

yes I understand that there will be a small variance.
please feel free to call me anytime and I will walk you through this.
Later
Mark D
717-773-5624

The key is to bleed a front AND rear wheel at the same time. That way you get a complete stroke to both master cylinders to push any air out. If you only do the front, the rear locks up and keeps the pedal from getting a complete stroke. No adjustment of the balance bar can overcome this. Also, when bleeding the fronts, remove the top caliper bolt and loosen the lower so you can tilt the caliper forward. If you look closely, the angle of the caliper allows air to be trapped at the top of the cylinder bore so tipping it a little will allow that pocket of air to escape.

The other problem is with the balance bar and mismatched masters and caliper piston sizes. Your calipers and masters should be sized so that the balance bar is straight across. I found with the FFR provided PBR front calipers and stock rear Mustang calipers, a 3/4" front and 5/8" rear masters provides a balanced system (the originally supplied 3/4" rear master in the older kit was too big and FFR has since changes to a 5/8") If you have aftermarket brakes and caliper then you need to do some research to figure the correct master size.

Went back out and re bled the brakes again. This time for some reason a lot of air came out and I instantly had a good pedal. Go figure.......

I had a couple of phone chats with Mark Dougherty who was really helpful. I followed his lead and centered everything up first. I pulled the caliper mounting bolts and rolled the calipers til the bleed screws were fully up right. Then I opened each bleeder and let the fluid gravity drain for a minute of so at each corner. That really made a difference and I have a much firmer pedal.. Mark explained the bedding process and I got that started. Each time i stopped it got better. So a big thanks to Mark for taking the time to explain all this silliness. I am sure the brakes will improve as they get used and I get them balanced.. thanks to everyone for their help..

Mark Dougherty is a legend. Things just work when I follow his advice.

Update,
After getting no where for several days, I gave up on brakes and continued on with other stuff until I could get this thing on the road for a little longer and bed in the brake pads. After 20 miles of 50mph, slam on the brakes to 5mph and back to 50mph, I never once got any lockup at all. I stopped all and pulled off the body convinced I would either fix these damn brakes or burn the thing to the ground. I used my Mity-vac on the left front brake bleeder and pulled a vacuum through the lines. After two full reservoirs of DOT4, I continued to get tons of micro bubbles. Vacuum pump holds great vacuum if I put my finger over the inlet so that is good. I used a pointed tip in the vacuum hose that goes into the bleed screw. With screw closed, vacuum holds great at 15". Crack the screw and bubbles galore. Disgusted, I decided to cut the problem in half by capping off the AN fittings at the front frame points and trying the pedal. Guess what, a nice firm pedal with only minimal gravity bleeding when lines were disconnected. So, problem apparently lies between the flex hose and the caliper. I have new washers coming to replace the crappy aluminum ones and I will try those this weekend. As of now, if this doesn't fix the problem, I am going to have to demand replacements from Factory Five for the calipers and hoses unless anyone here can tell me how to isolate the problem further. Note: all this is applying only to the front brakes. I haven't even started on the rears yet.
Please chime in 'cause you guys know this stuff much better than me. Thanks

The bleeders will leak air under vacuum. It gets in through the threads. Use the traditional method and you will see no more air.
Mike

Would speed bleeders help here? I have them but have never used them so I am only tentatively recommending them based on results I have read elsewhere. I have seen them marketed as Speed Bleeders and also Quick Bleeders.

I use speed breeders and really like them.
Also, follow the recommendations on bedding the pads as soon as possible.