Wilwood Park Brake Issue

[GT53]

Hey All,

I am installing the Wilwood mechanical park brake calipers and have run into a problem with pad clearance. On the DS, the caliper went on fairly easily but the rotor is quite difficult to turn by hand. On the PS, I can just barely get the caliper on at all and when bolted up, the rotor is all but impossible to turn.

What am I doing wrong? Thanks as always.

Greg

[michael everson]

It been a while but isn’t there an adjustment screw on the back of the caliper where the cable attaches?
Mike

[GTBradley]

It’s an issue for just about everyone. The parking brake drags on the right side. I oiled my brake cable sheaths and added a spring to help the cable release all the way. That and continued use cleared up the issue for me. Try rotating the lever on the back of the caliper to the home position and make sure the routing of the cable makes for easy turn radius on the bends.

[GT53]

It’s an issue for just about everyone. The parking brake drags on the right side. I oiled my brake cable sheaths and added a spring to help the cable release all the way. That and continued use cleared up the issue for me. Try rotating the lever on the back of the caliper to the home position and make sure the routing of the cable makes for easy turn radius on the bends.

Just to be clear, I don’t have the cables attached. I can’t even get the calipers to fit over the rotors. Haven’t progressed to hooking up cables.

[Hoooper]

Is it centered and tight on both sides, or just one side? Can you share pictures of the mounted caliper?

[GT53]

Is it centered and tight on both sides, or just one side? Can you share pictures of the mounted caliper?

Thanks Hoooper. I am severely technically challenged and after spending about 2 hours attempting to get a pic into this thread I gave up. I’ll try to sort out the picture thing later.

With regard to the E-brake issue, I managed to get the PS caliper mounted so I will do my best to describe the issue. With regard to both DS and PS, both calipers are indeed centered and everything looks normal. The issue is that in both cases the brake pads are flush against the rotors. I can turn the rotor by hand but it's obvious that the pads are rubbing as I can hear the friction and I can also see some marks on the rotor where the pads contact it.

I can’t find any info on adjusting the park brakes but surely there is a way to do so. I called Wilwood yesterday but the tech must have been a new guy because he put me on hold 3 or 4 times to consult with someone else. The only way I can see to adjust them are the 2 hex keys on the unit that move the flange in and out. Said flange can be pulled in and out when they’re not mounted so maybe they are the adjusters???

Greg

[Blitzboy54]

Thanks Hoooper. I am severely technically challenged and after spending about 2 hours attempting to get a pic into this thread I gave up. I’ll try to sort out the picture thing later.

With regard to the E-brake issue, I managed to get the PS caliper mounted so I will do my best to describe the issue. With regard to both DS and PS, both calipers are indeed centered and everything looks normal. The issue is that in both cases the brake pads are flush against the rotors. I can turn the rotor by hand but it's obvious that the pads are rubbing as I can hear the friction and I can also see some marks on the rotor where the pads contact it.

I can’t find any info on adjusting the park brakes but surely there is a way to do so. I called Wilwood yesterday but the tech must have been a new guy because he put me on hold 3 or 4 times to consult with someone else. The only way I can see to adjust them are the 2 hex keys on the unit that move the flange in and out. Said flange can be pulled in and out when they’re not mounted so maybe they are the adjusters???

Greg

A couple of simple questions

1. Is the caliper piston fully retracted? So when the pads are out of it is the piston flush with the body of the caliper or poking out?
2. Are you sure you have the correct sized pads? Possible they sent the wrong ones and they are thicker?

[Chopper]

I have the same setup, 6 piston Wilwood in the front and single piston integrated parking brake in the back. Once you get the system bled out, the performance is excellent, and I have been happy with the way it works.

As far as the parking brake, it's often a challenge and was for me as well. A few notes that may help:

1.) As suggested by Blitzboy54, you will have trouble if the caliper pistons are not retracted. These are screw style pistons, they must be rotated to retract. There is a special tool to help with this if you are not familiar. The bleed screws must be open to retract the piston in my experience.

2.) Wilwood provides shim washers....verify that you are correctly centered. Are both pads dragging, or just one side? There are two sets of instructions for these brakes, those provided by Wilwood, as well as a supplemental manual from FFR. Make sure to review both (in case one went missing from your order).

3.) The return springs on these calipers are not strong enough by themselves. They never will be, you need to add your own return springs. #40 compression springs work great, such as NAPA part # BK 7702139. The holes for the parking brake cable also need to be opened up slightly in my experience to get the end through and add a snap ring.

4.) I would not recommend using a Fox/SN95 mustang parking brake handle with these brakes, the FFR handle works much better.

Example of added return spring on my car:
https://photos.smugmug.com/Cars/Cobra/n-PLTRn/i-m2K8MNK/0/59f97e74/L/i-m2K8MNK-L.jpg

[GT53]

Problem solved. First off, thanks to all for your input.

I’m not certain if Wilwood has changed their park brake setup but here’s what I discovered. There are 2 brass (bleeder) bolts on either side of the piston, but they are not your traditional bleeder screws. What I figured out was that apparently Wilwood ships these calipers without any fluid. (At least the ones I have didn’t have any fluid)
I removed the 2 bolts, one at a time and added brake fluid. Didn’t take much to fill it up….I’m guessing 3 or 4 cc’s give or take. I then worked the lever that cycles the piston to move the fluid around and pump out any air bubbles, then tightened up the bolt. Then I moved to the other one and did the same except on this one, I put a squeeze clamp on the piston and held it in and then tightened down the “bleeder” bolt. After doing this I pulled on the handle and the piston extended as designed to push on the brake pads and then retracted back into the caliper, also as designed. The caliper slid onto the rotor with ease and now the park brake works as advertised.

I really do not know if this is the correct procedure for this particular park brake setup so “Caveat Emptor,” but being as it is only a park brake for now, I’m not concerned that there is a safety issue. Once I get it all hooked up and enter the go cart stage I will test out the “emergency” function.

Greg

I’m not ready to hook it all up but it doesn’t take much pull on the brake lever to clamp down on the rotors. I’m guessing 1 click or so on the E brake handle and the car ain’t going anywhere.

[racingandfishing]

This reminded me of another thread. Might read posts 644, 645 and 646 about applying the parking brake before the brake pedal as it may or may not apply.

https://thefactoryfiveforum.com/showthread.php?24163-Roadracer-s-997-build&p=500324&viewfull=1#post500324

[GT53]

This reminded me of another thread. Might read posts 644, 645 and 646 about applying the parking brake before the brake pedal as it may or may not apply.

https://thefactoryfiveforum.com/showthread.php?24163-Roadracer-s-997-build&p=500324&viewfull=1#post500324

Thanks for the heads up on the other thread. From those pics of the burned out brakes it’s hard to tell what’s what but being as the Wilwoods main and E brakes are separate calipers I’m thinking this wouldn’t apply.

However, rest assured that when the time comes I will duly test and re-test the braking system. It’s one thing to have a problem making the car go fast and quite another making it stop when one needs to stop AQAP. Many years ago I had a VW Bug that decided not to stop when I stepped on the brakes. I ended up rear ending the guy in front of me after literally bending the E-brake handle in a failed attempt to avoid testing out one of Newton’s laws. Sir Isaac was right yet again. Thankfully, no injuries and the car on the receiving had virtually no damage while my Bug was mashed on the front end. Anyone who has ever driven a Beetle knows that VW’s weren’t big on the go fast end of the scale and their stopping power was commensurate to their anemic thrust.

[Chopper]

Just a note...if you install the parking brake handle in the traditional FFR location, and wear a 4/5 point harness, you won't be able to reach the handle while you're buckled anyway. In the garage I normally just park in gear. But when I do use the parking brake, I still sometimes forget to take it off before I buckle up... In a Cobra I would consider these more of a parking brake than emergency brake. With the Wilwoods in particular, the same piston is doing both jobs.

[Mike.Bray]

Just a note...if you install the parking brake handle in the traditional FFR location, and wear a 4/5 point harness, you won't be able to reach the handle while you're buckled anyway.

I believe FFR duplicated the location as AC had it originally....for a right hand drive car. One of the reasons I went with the E-Stopp system.

[GT53]

Just a note...if you install the parking brake handle in the traditional FFR location, and wear a 4/5 point harness, you won't be able to reach the handle while you're buckled anyway. In the garage I normally just park in gear. But when I do use the parking brake, I still sometimes forget to take it off before I buckle up... In a Cobra I would consider these more of a parking brake than emergency brake. With the Wilwoods in particular, the same piston is doing both jobs.

I’m toying with the idea of mounting the E-Brake / Park Brake handle on the tunnel to the right of the gear shift. I’ve seen a few set up this way and although it sort of clutters up the trans tunnel it sure beats trying to reach the handle in the “traditional” place. I think someone on this forum has it set up that way. Might be Mr. Kleiner but I am not certain about that.

Greg

[RoadRacer]

I’m toying with the idea of mounting the E-Brake / Park Brake handle on the tunnel to the right of the gear shift. I’ve seen a few set up this way and although it sort of clutters up the trans tunnel it sure beats trying to reach the handle in the “traditional” place. I think someone on this forum has it set up that way. Might be Mr. Kleiner but I am not certain about that.

Greg

I did it in the 33, fwiw *shrug* - much better.

starts around here (https://thefactoryfiveforum.com/showthread.php?24163-Roadracer-s-997-build&p=428998&viewfull=1#post428998)

[rich grsc]

I did this on mine works great
https://www.ffcars.com/threads/parking-brake-mod-update-2.14915/
Thanks again dv/dt :D