C2 Brake Bleeding Frustration.

[Tony S.]

Re: C2 Brake Bleeding Frustration.

I had a problem bleeding my brakes on my recent '65 resto until I remembered that the rear calipers have two bleeders each-not just one. Maybe that will help.

Tony

[Dennis O.]

Re: C2 Brake Bleeding Frustration.

When I put DOT5 fluid in my '68, I had a real problem bleeding it. I had my girlfriend in the car doing the usual "down-up, down-up, down-up, now press it down and hold it" procedure. We did this for 3 days straight with no luck. I finally tried "down and hold it" and I then closed the bleeder screw, then had her let it up; then I opened up the screw and had her press the pedal down and closed the bleeder screw. By doing this a bunch of times, I got the brakes bled. I have never had to close the bleeder screw between cycles on any other brake job I've ever done, but it was what was necessary for this one. Whether it is a Corvette or DOT5 problem I don't know, but this is what was necessary. Hope this helps.

[Ralph B.]

Re: C2 Brake Bleeding Frustration.

When I put DOT5 fluid in my '68, I had a real problem bleeding it. I had my girlfriend in the car doing the usual "down-up, down-up, down-up, now press it down and hold it" procedure. We did this for 3 days straight with no luck. I finally tried "down and hold it" and I then closed the bleeder screw, then had her let it up; then I opened up the screw and had her press the pedal down and closed the bleeder screw. By doing this a bunch of times, I got the brakes bled. I have never had to close the bleeder screw between cycles on any other brake job I've ever done, but it was what was necessary for this one. Whether it is a Corvette or DOT5 problem I don't know, but this is what was necessary. Hope this helps.

I will give that a try ------- Thank you, Ralph

[Jim L.]

Re: C2 Brake Bleeding Frustration.

I finally tried "down and hold it" and I then closed the bleeder screw, then had her let it up;

If you aren't getting some fluid out the bleed port with each pedal depression, then each time you release the pedal, air will get sucked back into the wheel cylinder/caliper.

Once you do have fluid flow initiated, it's still a good idea to close the bleed port for the pedal upstroke. Otherwise, you risk pulling aerated fluid back into the cylinder/caliper.

IOW, always close the bleed port for the pedal upstroke.

Jim

[Domenic T.]

Re: C2 Brake Bleeding Frustration.

Actuallythe port is to be opened and closed with the pedal depressed, then lifted and depressed again and repeated till the pedal begins to stop short of the floor only to drop more as you open the valve letting the compressed fluid out. DON'T let them raise the pedal till you close the valve.
Repeat till the pedal stops high, then go's to the floor as you open the valve and let the fluid/bubbles out making sure the pedal is not let up till you have the valve closed.

The valve is always opened and closed with preasure on the pedal.

DOM

[Paul J.]

Re: C2 Brake Bleeding Frustration.

The valve is always opened and closed with preasure on the pedal.

DOM

Ralph,

As the others have said, DOM's statement above is the correct way to manually bleed hydraulic automotive brake systems.

Paul

[Dan D.]

Re: C2 Brake Bleeding Frustration.

Okay, I'll ask, why should you floor the pedal before you open the bleeder? I have always initially opened the bleeder, pushed the pedal, closed the bleeder, then released the pedal. I do this until I start to get pedal - then switch to your your method. -Dan-

[Paul J.]

Re: C2 Brake Bleeding Frustration.

Okay, I'll ask, why should you floor the pedal before you open the bleeder? I have always initially opened the bleeder, pushed the pedal, closed the bleeder, then released the pedal. I do this until I start to get pedal - then switch to your your method. -Dan-

You put pressure on the pedal before opening the bleeder to force air out immediately when the bleeder is opened. This eliminates the possibility of air getting in as the fluid starts to drain out by gravity. In reality, it probably makes little difference.

[Dan D.]

Re: C2 Brake Bleeding Frustration.

Yea Paul, Thanks. I do it my way until I start to get fluid - then pump with the bleeder closed. This is only applicable when lines have been replaced and there is no fluid in the lines. This is not a problem when one is just replacing wheel cylinders or calipers. -Dan-