trying to bleed my wilwood calipers and nothing comes out of the bleed screw?
 

I've not messed with the brakes at before tonight, they felt good and firm. I decided to install the proportioning valve tonight and decided to bleed the fluid out one of the calipers. the first thing I noticed was that I do not have a bridge line between the two sides? so how does pressure and fluid get from one side to the other? internal channel?


the second issue is that nothing comes out of the bleed screw? none of the screws seem to let any fluid out at 10 psi. do I need more pressure? in my other cars I was always cautioned about going above 15 psi because it can burst the fluid tank. none of the bleed valves had caps so I guess it could be corrosion but this car never saw rain and seems weird that they are all messes up.

There is an internal channel, you are correct. Try the old pump method and see if anything happens.

I only have one person, me. the way i've done the pump method in the past is pump brake, open, close, release brake, repeat, with 2 people.

once when my power bleeder line broke, I used a jack handle on the brake but I have a fixed seat so that will not work.


I removed one bleed screw and it does not have a hole all the way through. it does not look like corrosion. I would really like to get this wrapped up tonight or first thing in the morning.

I could try to pull the bleed screws and soak them but it seems odd that they all look the same.

anyone use a power bleeder? what psi? tired 15psi and no change.

10 psi with a Motive bleeder is plenty. There's something blocking flow.

yeah that is what I figured. I'm going to pull some of the bleed screws and soak em. that is really all I can do. perhaps can pick up new ones in the morning.

I soaked em for about 45 min in brake kleen and then hooked up a moto vac and I can get 25 psi vac on each one. seems strange that they would all be seized up but I guess it can happen. please speak if you have any experience with this

So these bleed screws must be speed bleeders with a check valve. I guessing they require the pressure from the pedal open. what a total pain. I got the normal bleed screws from the auto parts store. but they are longer, hope they fit.

Is this normal for all NBs? Any pics of these bleeders? Just curious.

No, the cars do not come with speed bleeders from the factory.

ok for the benefit of others, despite it makes me look like a brake noob, which I am not I think I know the issues. on the willwoods the bleed screw is not the brass assembly, like it is on all the oem brakes, Stoptech and Alcon that Ive owned, instead it is the much smaller port on the black fitting. Ive not verified this but it makes sense so well, now I know.

The bleed screw is really, really obvious on a Wilwood caliper.

ok, well is it like a normal bleed screw on every other caliper or is there a second smaller area on the screw that is separate from the flange, that when loosened would remove the bleed screw assembly from the caliper and not actually open the bleed valve.

based on the many cars ive worked on, essentially a two piece bleed screw is very rare and sounds like many people make this mistake. once it was explained to me in like 5 words it is somewhat of a face palm moment so ok I see that.

out of curiosity, show me another oem application or major racing brake maker that uses a bleed system like the one I describe on my wilwoods? Ive completely rebuilt oem calipers, Stoptechs, and Alcons so it is pretty safe to say my knowledge on brakes is above average. just sayin, simple enough of a confusion IMO sometime one overlooks the obvious when they've done a simple operation many many times.

perhaps next time you could take the time to briefly clarify how the bleeder screw work since this design is very unique to these calipers and not really used on other racing brakes (alcon, AP, brembo) or any oem Ive ever seen or even across the wilwood caliper line. I think that would be more helpful for others then saying it is very very obvious.

What is wrong with using speed bleeders?

I don't know that anything is wrong with speed bleeders but some have argued that the pump pedal method can force a master to over extend slightly and potentially damage seals but Ive never seen any evidence of this. most modern dealers have specialized fancy multi-circuit low pressure bleeders so it seems that a pressure bleed is the preferred method.

my experience happens to be with using a Motive power bleeder so that is what I like to use. getting in and out of the car to check fluid levels, pump the brakes, close lines is a pain in the ass. for me it is simple to just hook up the power bleeder and open each screw, close screw, done. I know not everyone can afford specialty tools but for those who track, I would think a pressure bleeder should be on the short list. I've used my heavily for over 10 years and found it a very worth while purchase.