Bleeding Wilwood Big Brake Kit

[RRoller123]

Putting new brake lines in the front, and I am wondering about bleeding the Wilwood Big Brake kit. It has (2) bleed screws on top, and (2) on bottom. My understanding is that we don't touch the bottom ones, ever, and ONLY bleed through the OUTERMOST top one? Yes?

Pete

[redcars]

YES!! On the top, but both of them.

[RRoller123]

OK, I am having no success in bleeding the Wilwood Brake system, and I need to get back to basics and ask a few basic questions.

Situation:

New Vacuum Booster Installed. Push Rod Adjusted.
New Master Cylinder Installed.
New FRONT Lines Installed, both Left and Right.
New Fittings all ends for Front Lines (ISO Metric Bubble Flare)
Reservoir cleaned and remounted.
New Feed Lines from the Reservoir.
New Clamps.

I can't get the system to bleed properly , so I need to make sure that I have the assumptions right:

I assembled the entire system, filled the reservoir, and started bleeding the TOP Right Front top outermost bleed screw. I am using a hand pumped HF vacuum bleeder. I assume that this will eventually bleed the entire system, master cylinder, lines, caliper, everything?

Just to be sure, I have the REAR line going to the solo FRONT position on the Master Cylinder. The RIGHT FRONT line goes to the Right on the paired MC position, and the LEFT FRONT line goes to the Left on the paired MC position. I assume that it does not matter which reservoir hose goes to which, but I have the Outermost feed going to the paired position (Front Lines) and the innermost feed going to the solo position (Rear line). All new lines, connections and clamps.



Also, I am just verifying that only the smaller fitting is to be loosened on the Wilwood calipers, NOT the larger one that the smaller one mounts into.

I am using a hand held vacuum bleeder, and the problem is that I just keep getting air through the outer line, even after almost a full quart of brake fluid has been drawn though the system by vacuum. This seems excessive to require a full quart through the single Right Front line??

Unfortunately this is getting very frustrating, and I need to figure out what I have done wrong. I am sure that all the connections are tight, and I was careful making the ISO bubble flares. I made them with a specialized brake kit made for that purpose.

Something is just not right.

Pete

[So Cal Mark]

correct, only loosen the small bleeder not the larger adapter in the caliper. Only bleed the top bleeders, not the bottom ones.

[ORFORD2004]

What about air coming from the thread. Put grease around your bleeder.

[RRoller123]

What about air coming from the thread. Put grease around your bleeder.

Thanks for the confirmation on the Wilwood nipples, Mark.

Thanks ORFORD2004, for the grease idea. I know that air leakage at the nipple can be a problem, but you can see clearly if the bubbles come out of the bleed nipple are large, and come out of the nipple itself, or if they are a small trickle of tiny/small ones from, that are leaking in from around the edge. Thus it usually can be determined which is which. I like the grease idea though, that is clever! I will try that. It should stop any side leakage.

One problem is that the Wilwood bleed nipples are ridiculously small, and you can't have the wrench and the bleed tube on there simultaneously. It is just ridiculous and there was absolutely no need for them to design it this way. The HF Vac Bleeder Pump is a waste of time and money for this reason. I ended up using some small clear hose that fit very tightly, and spun the bleeder open and closed with the hose, after loosening it with the wrench. After the final bleed, I pulled the hose and tightened the nipple with the wrench.

I found a small leak in a fitting back at the master cylinder and that probably explains why there were endless bubbles after almost a quart of brake fluid being used. I tightened it and was able to Gravity bleed both of the front lines with no air coming out, in short order.

So then I tested the brake pedal and it still goes straight to the floor as though there was nothing in place! I figure that maybe the Rear lines need bleeding, but of course I can't get either side's bleed nipple loose, so I soaked them both in penetrating oil overnight and will try to loosen them again this morning. Can one apply heat to the nipples to try to loosen them, or will this cause damage or a fire hazard? I could do it with a heat gun versus a torch.

If I can't get them loose, then I have no option but to replace the calipers. I think that trying to bleed at the flex hose connection, or at the T or elsewhere before the rear calipers themselves will just make a terrible mess?

Regarding the pedal going straight to the floor, is it possible for the vacuum booster arm to come off its yoke and not be actuating the master cylinder? I am amazed that there is absolutely no resistance and the pedal goes easily to the floor after bleeding the Front lines.

I suppose I could loosen the Master Cylinder and pull it away from the Vacuum Booster and find someone to push the brake pedal and see if it is actuating properly, but unfortunately Jeannie is still far too sick to come down to the garage and help with this.

Is there some way to ensure the full bleeding of new the master Cylinder while it is in the car? It is my understanding that the gravity method accomplishes this. Am I wrong on that? Do you have to pump the pedal a few times to move the air around inside the Master Cylinder? or can it be accomplished statically with just the gravity method? That is what I thought was the case, maybe I am wrong? I am perplexed by the pedal still having no resistance after the fronts were gravity bled.

Needless to say, I will be very glad when this project is over, the whole thing has been a nightmare. Oh, and a word to those doing this in the future: Be careful! It is very easy to put the new Vacuum Booster in 90 degrees out of proper orientation. Ask me how I know. The intermediate plate is mounted with a rectangular pattern of studs to the firewall, but the Vacuum Booster mounts in any orientation to the intermediate plate with a SQUARE stud pattern. I had it 90 degrees off, which would have put the master cylinder over on its side. Hahahahah! I had to redo the entire project from scratch the other day, just as I was going to install the new Master Cylinder.

Live and learn.

[Nanonevol]

If you do have to get new rear calipers, O'Reilly's has them fairly cheap and will take your old ones for credit. I wouldn't try bleeding at some other point in the rear. Hopefully that's your problem - the rears not being bled. Wish I could be more help.

[RRoller123]

I got the rear bleeders open without damage. The overnight penetrating oil did the trick. Have all (4) corners gravity bled now, but pedal still goes to the floor. I think I will lengthen the push rod a little and see if that does it?

I still don't have any knowledge of whether bleeding the new Master Cylinder while in the car, by the Gravity method works? Am I mistaken in this?

[RRoller123]

The Problem appears to be solved.

The rears had a large amount of air in them, even though the line/s had not been changed. Especially the LR. Very interesting, and unexpected. Not sure why that would be, but I was able to visually see that one from the driver's seat while I pumped the brake pedal. So I immersed the end of the clear tubing into brake fluid in the fluid waste can, and pumped the pedal a few dozen times. A lot of air came out, along with some cloudy fluid.

Now the pedal is firm and near the top of travel.

Going around again and bleeding from the beginning, RR - LR - RF - LF. just to be sure. Then an easy nearby road test to make sure I have the Booster Rod length set correctly.

Side note: IMHO The Wilwood bleeders are far too small, and they rock in their seat, even when only opened maybe 1/8 of a turn, which lets air in around the threads. If you only open them only very, very slightly, you can keep the air from infiltrating, but just barely. I chose to just pump about a 1/2 quart through the RF side, just to be sure that I flushed out all the trapped air.

Pete

[ORFORD2004]

The best way to bleed is 2 peoples. One at the pedal, the other one at the caliper.
Go ask your neighbor loll!!!!!

[RRoller123]

No. Invite over for tea and biscuits, yes. Rolling around on a filthy cold concrete garage floor, not so much.