Gravity Bleed

[s4dustin]

So the car is up in the air, I have hoses from the bleeder to water bottles to drain. Opened everything up and I have some fluid coming out. How long should I leave all this open? I am running a full wilwood disc brake set up, 13in 6 piston fronts and 12 in 4 piston rears. I cannot seem to get all the air out. I had a friend who did this, left it open for a week and then his brakes were perfect. Any suggestion?

[gort69]

A week seems a bit excessive. If the reservoir(s) go dry, you get to start all over. Buy, beg borrow or steal a Motive pressure bleeder and you can be done with it in a half an hour.

[JimM]

I used gravity for days, and then a miti-vac trying to bleed my wilwoods. Must have moved a gallon of fluid thru them. Tapped on everything to dislodge the lil bubbles. yada yada yada.

Agree completely on the pressure bleeder.

Another thing I found (is your car runnning, being driven??) is I'd get a random low pedall, that would come up in a pump or two.

A friend suggested it might be caliper knockback, from the c-clip axles moving in and out. He suggested a 2 lb RVP in the rear line. I did, and my pedal has been perfect ever since.

[Vegas69]

I like to use a vaccum pump to move the fluid and get most of the air out, then I gravity bleed until I don't see any air bubbles with a flashlight. A 2lb residual won't do anything for pad knockback. It's just not enough. I have it and have tried it.

[s4dustin]

I used gravity for days, and then a miti-vac trying to bleed my wilwoods. Must have moved a gallon of fluid thru them. Tapped on everything to dislodge the lil bubbles. yada yada yada.

Agree completely on the pressure bleeder.

Another thing I found (is your car runnning, being driven??) is I'd get a random low pedall, that would come up in a pump or two.

A friend suggested it might be caliper knockback, from the c-clip axles moving in and out. He suggested a 2 lb RVP in the rear line. I did, and my pedal has been perfect ever since.


I have bleed the heck out of these, but the problem is that I have so much pedal fluctuation that the pedal is never in the same place twice. Someone just yesterday suggested the 2 lb RVP...

I will see what happens with the gravity. Initally, it moved fluid out, now nothing is moving...

[Vegas69]

Have you driven the car or is the pedal fluctuating on the lift?

[JimM]

2lb residual won't do anything for pad knockback. It's just not enough. I have it and have tried it.

It ABSOLUTELY fixed mine right up. I'd several months of driving it, and would get a low pedal often, sometimes low enough to light the idiot light.

I had a 2 peice rear line, with just a junction where the stock prop valve would go, so I unscrewed it, screwed in the rvp, rebled the brakes, and never looked back.

Pedal has been "high and hard" ever since.

[Skip Fix]

The newer plastic pressure bleeder top I have is a POS, it seals MOST of the time, and just when you think it is sealed leaks brake fluid all over! Great for chassis paint underneath!

I have an older metal one I need to add a new gasket to and try.

[CarlC]

Hey Dustin,

Did you bench-bleed the master cylinder? If not you will chase air forever and never get it all. Also, some later model MC's have another bleeder on the MC body that needs to be bled as well.

I use a vacuum pump and an old pickle jar to act as a vacuum bleeding system. Works great and only cost $15. I could make an adapter to pressure bleed but I don't like to do that with plastic MC reservoirs.

[fordsbyjay]

Hey Dustin,

I use a vacuum pump and an old pickle jar to act as a vacuum bleeding system. Works great and only cost $15. I could make an adapter to pressure bleed but I don't like to do that with plastic MC reservoirs.

That is a good idea. I have a hand pump mityvac unit and I have never really like it. Where did you get your vacuum pump from?

[Vegas69]

It ABSOLUTELY fixed mine right up. I'd several months of driving it, and would get a low pedal often, sometimes low enough to light the idiot light.

I had a 2 peice rear line, with just a junction where the stock prop valve would go, so I unscrewed it, screwed in the rvp, rebled the brakes, and never looked back.

Pedal has been "high and hard" ever since.

Are you sure it wasn't air? Wilwood will even acknowledge it doesn't work. I've talked to them about 7lb springs behind the pistons and they said it's been tried and won't work either. It didn't do anything for mine. 2lbs is not much to move a caliper piston. I've now switched to a tapered bearing and it's acceptable on the street. On the race track it's managable but still not ideal. I've thought about trying a 10lb but that's not ideal for strreet driving.

[s4dustin]

I have not driven the car yet, it is still up in the air with everything still open. Bench bled the master. Everything is wilwood including master.

[monteboy84]

I'd run a pressure bleeder on it. Open all your bleeders and run a tube into a bottle at each corner, then turn on the pressure and slowly pump the pedal.

With the pressure still on, close all the bleeders, then check each corner for air as you normally would.

-matt

[CarlC]

Surplus house in Los Angeles. Apex Electronics. Likely not cost effective if shipping is needed.

[firebob]

I've always had to have help bleeding brakes. You know, someone to push the pedal while I opened and close the bleeder screw. Today I tried to do it by myself.

Bench bled the m/c first of course then I did one wheel at a time(as before). Put the hose on, other end in a jar placed about level with the caliper. Opened the screw. Went inside and operated the pedal a couple times slow and then a couple of quick strokes. Repeat for a couple of cycles, slow then fast. My idea was the slow would push the fluid through and the quick strokes would draw fluid past the rubber cups in the m/c before it would draw it back in the bleeders. Pushed a couple of ounces through each wheel. All done. You have to make sure the res doesn't go empty too soon. The master will push it through pretty fast. Got a good solid pedal now. I'll do it this way from now on. My wife always hated to help anyways.

Robert

[FJ4JAKE]

I made a pressure type bleeder out of a garden sprayer, a flat piece of metal, and about $6.00 worth of brass fittings..... Redneck...probably... worked like a charm though....

[MonzaRacer]

For the price this is probably the simplest unit you can get(http://www.brakebleeder.com/index.php?main_page=product_info&cPath=2&products_id=16&zenid=e55v0uascvmj6iq3c1rcnuhni3), I have my old Veri-ject pro(discontinued) then I bought a new Maxi-ject pro and just got sent a new Maxpro because they are goingto put my picture and testimonial in their new manual.
I love my Phoenix injector, I even made my own cap to fite quart bottles of brake fluid, by drilling a hole just under 1/4" in a cap and simply inserted a piece of brake line in it.
I'll use this tool( almost daily) to my benefit and profit.

[fordsbyjay]

I have an old pressure bleeder that I bought from a shop going out of business. It is a round metal canister with a rubber bladder inside. I have never had any success with it at all. Too much pressure and it leaks at the M/Cyl. Too little pressure and it doesn't seem to do anything. I must be doing something wrong.:pat:

[MonzaRacer]

hey fordsbyjay, most of those require a reduction regulator or the pressure gets too much.

Most of them have a chain or clamp to hold them on the master cylinder then you open bleeders. always wanted one of those but now I use my Phoenix Injector.

[fordsbyjay]

hey fordsbyjay, most of those require a reduction regulator or the pressure gets too much.

Most of them have a chain or clamp to hold them on the master cylinder then you open bleeders. always wanted one of those but now I use my Phoenix Injector.

Correct there is a chain that goes around the m/cyl and you tighten it down. There is a valve on top to adjust the pressure as well. I find at the lower pressure it doesn't seem to push the fluid.

Once it is pressured up are you supposed to pump the pedal or does it push right thru? My 56 does not have any kind of proportioning valve, it is straight from the m/cyl to the wheel cyls.

[staged67gspwr]

Guys i`m having the same problem myself,i must`ve bled my system 100 times and my pedal still goes down randomly i really dont know what else to do anymore any suggestions?i have wilwood 6 piston calipers all around,7/8 master,and wilwood proportioning valve,like i said i dont know what to do anymore?