wilwood problems

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coreyg

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Kind of a long story but it might help with getting a answer. So I bought a 71 plymouth scamp 3 years ago to build a nice drivers car. I've been working on it and getting upgraded parts for the car, and wilwood brakes was my first upgrade. I call wilwood and spoke to one of the techs and he gave me all the part numbers I needed for the front disk brake kit. So I went down to Jegs and picked up the kit he recommended. Got all the brakes on the front off and went to install the wilwood kit and it wouldnt fit. So I called wilwood and he told me to send pics and he still had no answer for me about why they don't fit. Posted on here and with in minutes I had my answer, wilwood had the 71 scamp listed as a B body. I called wilwood back and they argued for a little bit until someone there informed the tech that the 71 scamp was indeed a A body. So wilwood sent out the proper brackets for the A body and said the calipers where the same so just reuse them. Got it installed and was having issues with proper pedal pressure. So I called wilwood again to see which master cylinder they recommended, the tech told me to get a 1" master cylinder, so went back to Jegs and picked up the tandem 1" master cylinder with proportioning valve kit. Got it installed and still the pedal was soft and squishy. So I ordered the rear disk brake kit thinking maybe the rear drums were the issue. Got the rear kit installed and same result poor braking and soft pedal. Called wilwood again and the tech said my master cylinder was to big and wasn't building enough pressure. So I had to drop another $350 for a 7/8" m/c. Right away I could tell it was building better pressure but the pedal was still soft. So I bleed and bleed and bleed, I reverse bleed, used a vacuum bleeder, gravity bleed, and manually bleed them with no luck. So I capped off the main circuit on the m/c so I was only powering the rear brakes and the pedal was solid. Capped off the secondary circuit on the m/c so only the fronts were powered and soft pedal. So I figured one of the front lines are bad even though I see no leaks. I ended up capping of the backs and one of the front and the pedal was still soft, capped off the other front and the pedal was still soft. So back to tech support at wilwood and this time the guys said that my m/c was to small and I need to put a pressure gauge on the system to see what the pressure is, I should be doing that tomorrow. But I called wilwood again today and a different guy suggested a 15/16 m/c so I figure wilwood techs have no clue on what they are talking about so here I am on the forums hoping someone has a suggestion for me.
 
Which reservoir are you sending to the front ?
Where are you "capping" your lines?
I like the modulation feel of the 15/16 best .
Some guys have reported that some brake systems demand a 1" or bigger mc, just for adequate volume. Personally I don't think so...... but I ain't all-knowing.
Off the hop I would suspect an air pocket trapped in the M/C between the two braking chambers.
master-brake3.jpg


The primary line is supposed to go to the front brakes. Take a close look: if you cap the rear line so that no fluid can go out, then any air stuck in front of the primary piston will make a nice little expansion chamber, and you can bleed forever and not get it out. Take a look into your primary reservoir, the rear one, and locate those ports. They have to be at the high point during bench-bleeding.
 
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The front are plumbed to the main front reservoir and the rears to the rear. I capped them right at the m/c and then each front on the bottom of the proportioning valve
 
This is the m/c I have the primary reservoir is in the front.

tandem_master_kit_w_bracket-sm.jpg
 
It has 4 outlets 2 for the primary and 2 for the secondary. I only bench bleed the two that are going to the portioning valve could there be air trapped in the 2 on the other side that are plugged off.
 
Seems to me, a 7/8" would give a softer pedal than a 1". And, obviously 15/16 is between them. I would not change to a 15/16 if the other two didn't give you the desired feel. What do you have on for front pads? Maybe something is going on with that proportioning valve(?). Sounds like air is trapped somehow, somewhere.
 
If the pedal is soft, it's either air in the system, or the caliper isn't parallel to the rotor, and you have flexing in the mounting bracket
 
J Glenn said:
The primary is the one closest to the firewall... like the drawing that someone posted. Right?
Click to expand...
I assuming the primary is the front on this m/c. its the larger reservoir and plumbs the portioning valve that is marked front.
 
replicaracer43 said:
If the pedal is soft, it's either air in the system, or the caliper isn't parallel to the rotor, and you have flexing in the mounting bracket
Click to expand...
I did notice today that the caliper isnt 100% centered on the drivers side its about 1/16th off center.
 
coreyg said:
I did notice today that the caliper isnt 100% centered on the drivers side its about 1/16th off center.
Click to expand...
Offcenter doesn't matter as long as she's sitting parallel to the rotor centerline and not touching anything that she's not supposed to.

I don't know anything about Willwood M/Cs which are usually backwards-plumbed compared to any and all Mopars A-bodies I have ever worked on.
I like my brake-pedal directly connected to the primary piston, operated mechanically. In a Mopar mc, the secondary piston is operated hydraulically ...... until a brake failure occurs; then the back-up mechanical system comes on line.
 
Without regard to what goes where, if you cap the mc at the frontmost port, leaving the rear port operational;
Then the frontmost chamber is hydraulically locked (assuming it is air-free), and so whatever is connected to the rear port should show a hard pedal.
If it does not; Then either there is a mechanical problem in that system, or a hydraulic problem.......... or there is air in the frontmost chamber acting like a spring.

Therefore
1) I recommend always to rebench-bleed the mc looking for the telltale bubbles escaping from the compensating ports. During bench-bleeding, sometimes you have to introduce one-way valves so the fluid doesn't just shuttle back and forth; I use my fingertips. You may have to bench bleed with one end higher than the other.If you cap all the ports the pedal should get rockhard as the only flex will be in the firewall. After re-connection, if the pedal is still soft;
2) I recommend to C-clamp the pistons into their calipers , all of them and pedal test. If still soft, obviously you have a hydraulic issue. And if now hard, just as obviously , you have a mechanical issue.
 
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AJ/FormS said:
Without regard to what goes where, if you cap the mc at the frontmost port, leaving the rear port operational;
Then the frontmost chamber is hydraulically locked (assuming it is air-free), and so whatever is connected to the rear port should show a hard pedal.
If it does not; Then either there is a mechanical problem in that system, or a hydraulic problem.......... or there is air in the frontmost chamber acting like a spring.
Click to expand...
I got ya so more then likely I was hydraulically locked and the rear calipers didn't create the hard pedal but not being able to fully push in the m/c was creating the hard pedal.
 
I used the Stainless Steel Brake Corp (SSBC) kit and it worked great. Before that (about 10 years ago), I called Willwood several times and got huge run arounds from the techs. One tech actually told me that Willwood brakes were not recommended for street use. WHAT???? That was all I needed to hear. I went with SSBC.
 
FYI check the 7/8 master as there was a recall on them for this very issue. My 7/8" master is on the recall list but it's working. I'm planning to send it in shortly to get it replaced with the new valve design.

You can google Wilwood 7/8 Master recall and get the product numbers. Here's a link... https://www.wilwood.com/Pdf/Recalls/RDCONL-17E030-0986.pdf


What is the Defect/Reason for this Recall?

Wilwood® believes the brake cylinder seal in the front circuit may become deformed, bypassing hydraulic fluid and resulting in loss of braking in front circuit. Unexpected loss of brake pressure and pedal feel in front brake circuit may increase the risk of a crash.


Riddler
 
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I use 4 wheel wildwoods with a 7/8 master. I got mine from Bill at RMs who knows their products better than the low wage techs do.

Did you bench bleed the master? The 7/8 pedal will move father and easier but squish is air.

There is nothing wrong with Wilwood brakes. Service and techs, sure, but their products are top notch. I've run them on circle track cars and street cars.
 
Riddler said:
FYI check the 7/8 master as there was a recall on them for this very issue. My 7/8" master is on the recall list but it's working. I'm planning to send it in shortly to get it replaced with the new valve design.

You can google Wilwood 7/8 Master recall and get the product numbers. Here's a link... https://www.wilwood.com/Pdf/Recalls/RDCONL-17E030-0986.pdf


What is the Defect/Reason for this Recall?

Wilwood® believes the brake cylinder seal in the front circuit may become deformed, bypassing hydraulic fluid and resulting in loss of braking in front circuit. Unexpected loss of brake pressure and pedal feel in front brake circuit may increase the risk of a crash.


Riddler
Click to expand...
Yeah mine isn't part of the recall already checked on that.
 
roccodart440 said:
I use 4 wheel wildwoods with a 7/8 master. I got mine from Bill at RMs who knows their products better than the low wage techs do.

Did you bench bleed the master? The 7/8 pedal will move father and easier but squish is air.

There is nothing wrong with Wilwood brakes. Service and techs, sure, but their products are top notch. I've run them on circle track cars and street cars.
Click to expand...
I just can't find were the air is coming from, no visible leaks any where.
 
i have Wilwoods onmy '72 Scamp . I used a master cylinder from a '73-76 Dart/Valiant disc brakes non-power . I bled the m.s. seven times , soft pedal . I bled the system 5 times , soft pedal . I was pulling my hair out . the idiot light would not go out . Finially found that the rear brakes were in need of adjusting tighter . the pedal is still soft but it stops like crazy . Oh, I forgot, I purchased an adjustable brake pedal push rod , too . If I may suggest , drive the car and see how it stops . If it stops great , you are golden .
 
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