Two Brake Bleeding Questions

[Robert S.]

I will be doing a one person brake bleed on my 74' after replacing the master cylinder. Two questions:
1. On the rear do you bleed the inside of the caliper first or the outside first?
2. I plan to try gravity bleeding for the first time - do I route the drain tube from the caliper into and below the fluid level of a jar partly filled with brake fluid or do I just route the tube into the top of a jar to catch the fluid that drains out?

[Clem Z.]

Re: Two Brake Bleeding Questions

rent a pressure bleeder because with gravity bleeding you have to leave the M/C cap off and this introduces a lot of moisture into the fluid. GM now days uses a translucent M/C reservoir so you can see the fluid level instead of opening the cap.

[Martin N.]

Re: Two Brake Bleeding Questions

I agree with Clem, I tried the gravity bleeding with very little success, rent a power bleeder and make your life easy.
Marty

[Michael G.]

Re: Two Brake Bleeding Questions

I will be doing a one person brake bleed on my 74' after replacing the master cylinder. Two questions:
1. On the rear do you bleed the inside of the caliper first or the outside first?
2. I plan to try gravity bleeding for the first time - do I route the drain tube from the caliper into and below the fluid level of a jar partly filled with brake fluid or do I just route the tube into the top of a jar to catch the fluid that drains out?

Robert,

Let me answer your question. Should you want to try gravity bleeding first, on the rear caliper start with outer portion of the caliper. Then gravitate (pardon the pun ) to the inside.

[Edward J.]

Re: Two Brake Bleeding Questions

I will be doing a one person brake bleed on my 74' after replacing the master cylinder. Two questions:
1. On the rear do you bleed the inside of the caliper first or the outside first?
2. I plan to try gravity bleeding for the first time - do I route the drain tube from the caliper into and below the fluid level of a jar partly filled with brake fluid or do I just route the tube into the top of a jar to catch the fluid that drains out?

Robert, I like to bench bleed the master first, put in a vise, generally the give you a couple of plastic fittings and hoses with the master cyl.,route hoses into bowls and depress plunger (with master cylinder just about full of fluid)until all the air bubbles are removed, and install and bleed system.

[Peter J.]

Re: Two Brake Bleeding Questions

Robert,
I bench bled my 66 P/B master cylinder and then I took John Hinckley's advice and bought Motive Products pressure bleeder. What a difference that makes, I had good pedal feel in less than ten minutes the first I used it on my car. Since then I have helped a couple of friends on their cars with it and it worked perfectly evey time.

[Paul S.]

Re: Two Brake Bleeding Questions

Robert,
I bench bled my 66 P/B master cylinder and then I took John Hinckley's advice and bought Motive Products pressure bleeder. What a difference that makes, I had good pedal feel in less than ten minutes the first I used it on my car. Since then I have helped a couple of friends on their cars with it and it worked perfectly evey time.

I did the same when replacing the MC on my 67--I already owned the Motive power bleeder (been using it for years on my 911), bought the chevy adapter plate and used a piece of wood and a 6" C clamp to secure it to the MC. When bench bleeding the MC I bought clear plastic tubing at Lowe's so I could see the air bubbles going out of the tube. I quit bench bleeding when no bubbles on each compression stroke.

When bleeding the calipers, I made sure to tap on the calipers with a rubber mallet to dislodge bubbles. I did that while draining, and also after it appeared all air was out, I closed the bleeder and tapped on the caliper some more and re-opened the bleeder, repeat until no air bubbles. Then move to the inner bleeder. Same process. Then move to next caliper.

When I was done, I was done (meaning the brakes were good) and I won't need to touch until it's time to flush again.

Once you have a Motive power bleeder, you'll wonder why you ever fooled with gravity bleeding or the "buddy" system.