Ok guys more issues that I am scratching my head over. Might be too much stress and just not having my head into it or I am too close and not seeing something.

Due to the car sitting for 2 years, the car being heavier than what the old Wilwood rear brakes were rated for, the M/C bypassing, a locked wheel cyl and finally a caliper not working correctly(not retracting at all.

I have changed everything but the lines, line lock and the 2psi residual valve I had on for the front brakes. So now I have all the lines back on, the front and rear brakes back on, Wilwood disc all the way around. I used a vacuum bleeder to get fluid into all the calipers but they seem to still be moving air. I have gone through a quart of fluid and still getting air.

The pedal also goes right to the floor no pressure shows on the brake gage. I do not think the calipers are fully full with the pistons extended to the normally engage point.


Still air in the system?
Is a quart normal for all new calipers (4 piston), M/C and lines?
Should I rig up something to let it gravity bleed? I would have to make something as the M/C is in the floor. But I could hook it up to the brake gage and do it.

Thoughts?

Tony .. have you bled both bleeders on each caliper...
are you sure you dont have a fitting loose... did you
bleed the master first... you could have a bad master...
a QT should do the whole job easy... thats one thing
about using a vac bleeder.. you dont use pressure and
it sucks in air and doesnt show leaks easily(no fluid
leaking)

Bench bleed the master first, this can take a bit of time. Then gravity bleed the entire system starting with the farthest bleeder from the master cylinder. Go around the car several times. Apply the pedal to push the pistons out, do not pump it rapidly as this just airiates the fluid. Gravity bleed some more then with an assistant pressure bleed starting at the farthest bleeder first by applying pedal pressure, opening the bleeder than closing it before the pedal is released again.

I'm sure you know all this, sometimes we just need a reminder.

Thanks guys,

the M/C was bench bled, well it was in place and bled. I will figure out a way to gravity bleed the system. With the M/C in the floor I will have make something and use the port bleed at gage which is higher than all calipers.

I will then bleed it around like stated. Yes that is what I figured meaning I was getting it right but good to hear I was only missing the inside bleeders which I missed on purpose figuring I would be able to get pedal and bleed those when I was doing a final bleed.

Thanks again, I am on it.

How much are you opening the bleeder?

I had a similar issue when converting over a 71 Charger R/T from brake drums to the Wilwood disc's. Mind you this was a brand new kit. Figured it'd be an easy afternoon job since I've done the conversion many times before. BTW, I hate safety wire lol

I put everything together, used a vacuum pump to bleed the brakes as always and no pedal. I figured there was air in the system so I kept bleeding and bleeding to no avail. I think I put close to 3 qt's through it. Figured I got a bad MC so I ordered another one. Still no help.

On my 2nd day of trying to get some pedal pressure I pulled the wheels off, had a bud jump into the car and lifted him on the lift and planned on bleeding the brakes the old way. However this time around I used a small dead blow hammer and tapped on the calipers in hopes to dislodge any trapped air at the pistons. I remebered this trick when installing a Baiar disc brake system in a Mustang.

I started on the right rear tapping the calipers with the dead blow while bleeding when I seen a burp of air come out of the line and he hollars down...I got pedal, not much and its soft, but I got pedal. A short time later the brakes worked like a million $$$. Just my

The rubber mallet works well to remove trapped air, just some light taps, and as MR.P Body stated you must bleed both bleeders on each caliper.

Based on your description, is your master cylinder LOWER than the calipers??

I will use the tap trick when I am ready to maually bleed them.

Yes M/C is lower.

Bleeder is open 1/2 to full turn, it is loose/woobly.

I have the 2psi residual valves in the lines as needed.

I got home late and started on the gravity bleed set up. I am going to gravity feed the fluid through the port in the brake pressure gage, or hope to. I will finish that when I get home from work and see how it goes. If that does not work I will do it the old fashion way, manually. I need to get the car back up on jacks and wheels off so I can bleed without getting fluid all over the place. Yes I will do both bleeders.

Tony, get some hose to fit on the bleeder and save
the fluid coming out to a jar.. saves on making a mess

That is part of my little set up. 1/16 hose is hard to find here in Tucson. Those bleeders are tiny....

I have a clean container too. Going to put a hole in the top and feed the hose in so it is a little less mess.

Bunch of info on the internet re using a 2lb residual valve when the MC is lower than the calipers. Among other things, that condition can cause flowback from the caliper, retracting the pistons, resulting in longer pedal travel.

A 2lb residual valve, used mainly to keep the flow of fluid from flowing back to the master cylinder from the calipers and brake lines in applications that have the lines and or calipers higher than the master cylinder.

If you tighten the bleeder to tight it will cause the brass seat to crack and you will never get a peddle. I have done that a few times on my stuff.
Sometimes a line lock has a off size and normal break fittings seem to be just out of tolerance.
Once you start getting a little peddle just keep pumping and holding. Leaks should show them selves after a few cycles

Residual valves are designed to keep the pucks or shoes close to the rotor or drums. It does not matter if they are floor or firewall mounted. All the chassis cars that I have seen all have the m/c mounted on the floor. Disc brakes require 2 lb valves and drums use 8-10 lb valve. It sounds as if the OP has all the componants he needs, just has to get the air out.

I found 2 leaks letting it sit over night. The fitting at the M/C is leaking and one of the fittings going into the residual valve for the front brakes.

Both have been tightened up. The residual valve may leak again. If it does I will pull it off the car and tighten it on the bench.I cracked the bleeders at the fronts on both sides and had fluid trickle out. did not see any bubbling though. The auto store by my house did not have half the stuff I needed so I will be finishing that up today. Hope to have teh gravity bleed set up tonight.

I even had fluid at the head of the gage so i am really thinking I paniced early and just need to keep bleeding manually because of the calipers were fully contracted, plus all the air in the lings.

Anyone ever use the bleeders with the check valve in them? Are they any good? Saw those but did not want to spend the $40 it would take to get enough for the Wilwoods.

Save your money on those bleeders Tony... once you
get it bled you wont touch it for years... its not
like you have to do this every week

Got you but I am a one man band down here... I know there are guys here in Tucson but no idea how close they are to me.

I will save the $$ already blew too much on this little project...

FWIW.. My M/C is floor mounted and I took the residual valve out of mine and it worked better..



Chris..

Chris I will keep that in mind if I keep having issues.

I did get the leaks stopped. Bone dry when I got home. So sitting for 24 hours it did not leak.

Not to button it up and get them bled.

Tony, find someone and pressure bleed them, it's a system that forces fluid thru the systemand pushes the fluid thru under a slight amount of pressure, I have a friend that owns a repair shop and is a one man band, and thats the only way he will do it any more just hook the system to the master cylander resivoir and push it thru.

I'm hoping to get my neighbor to help tonight. If not I have someone lined up for the weekend. Don't really want to wait until then but no choice.

Ok guys I finally got the brakes to bleed correctly.

It took some figureing, re-reading this post and some other issues but it is done, for now.

I have 600psi and an inch off the stop for the pedal. The calipers release nicely too.

I had a ton of air in the system, ended up rebleeding the M/C, none there but wanted to make sure. Put in a 10PSI residual valve. The 2 was just not working, it seemed to let too much fluid back into the M/C. I am thinking my calculations are wrong on piston dia, vs travel vs volume needed. The pedal should only go about half way before it stops moving. I use about 6" of the 7" movement. I am debating on putting a second M/C in the car but not wanting to spend the $$ to do so, but then again, we are talking about stopping...

I got all 4 corners bled, then went through and tapped them with a mallet. Good call as it released some air in the system. I found 2 leaks in the system after it was bled, so fixed those and rebled.

Only thing left before the test spin is to safety wire the bolds holding the caliper bracket, wheels and tires on, clean up, put some wriing back in place and go for a spin in the hood...

Thanks again for the help guys!!

Tony... make sure its all bled out but if your using
6" of travel with only 600 psi you will want a larger M/C

I thought I had the largest available. I will check the M/W site. A friend down here is a round pounder and I am having them come over to peak at it and see if their chassis guy can build someting that will work in the limited space I have to hold 2 M/Cs then just dedicate one to front and one to rear.