Bleeding brakes- not working

[bergie]

I have been trying to bleed the brake lines on my 1950 f1 and am having no success. I searched the threads on this site and saw all the similar problems and suggestions to solve. I saw where some wheel cylinders may have been manufactured incorrectly but I also saw where some said the master reservoir needs to be “bench bled” at each outlet port before being reinstalled. It is new and has never had fluid in it before. Is this a real thing? The pedal has no resistance at all. It simply falls to the floor. Any ideas. Thanks in advance.

[rbone]

Yes, bench bleed the master cylinder before you put it in the car. Be careful to put some scrap pieces of wood or something similar between your vice and the master cylinder. Some years ago I got some barbed fittings to fit into the housing outlet(s) and I just use some clear tubing. I use a wooden dowel to pump the cylinder. Do it slowly until no bubbles.

If that doesn't fix it and the pedal has no resistance at all, are you sure the linkage to the master cylinder is working correctly? Also, double check for leaks at all fittings.

Hope you get it fixed. Brakes are simple, but they can be a pain in the backside.

[paul2748]

If it's single bowl master it usually does not need to be bench bled. What procedure are you using ? Speed bleeders ?


Usual practice is to start from the furthest cylinder from the master, which is the right rear wheel



[

[bergie]

I first tried the two person, pumping while the second person manned the bleeder valve (right rear). Then tried vacuum (Mity Vac kit). No fluid either method.

[Mart]

Single or dual?
It wasn't f1 cylinders that were drilled wrong but early ford rear types.

A single master will self bleed with gentle short strokes.

I have found that the only 100% reliable method is a pressure reservoir system.

I used this three times lately and it worked very well indeed, in one case where all other methods including vacuum had failed.

I use an old "Gunson's Eezi Bleed" Kit. Hopefully a local equivalent is available.

Making the adaptor for the master cylinder is the only tricky part.

I have a video in preparation that will show it being used.

Mart.

[69a]

Sponsored Links (Register now to hide all advertisements)

Make sure your plunger is coming all the way back and then have about 1/8" freeplay disconnect the brake line at the first junction. Make sure you keep the fluid in a suitable container and away from paint etc. Just use short strokes to begin with. It should bleed itself. You should not need to bench bleed a single master cylinder.

[rotorwrench]

Bleeder nipples are sometimes a loose thread fit to the wheel cylinders. I wrap them with teflon tape and screw them in before bleeding. Make sure you have an open brake line to the rear, They can get plugged if setting around too long. Replace any flex lines. They can block flow if they are deteriorated.

[bergie]

I now have the reservoir out and in a vise. Now I can see that the plunger is frozen (rusted?) in the fully “in” position. Is it feasible to attempt to rescue/rebuild this unit? Will removing the brake switch on the rear of the unit allow access to plunger from that end where some sharp taps could break it free?

[Ford Freak]

I would just call Mac VanPelt and order a new one. (513) 724-9486 . If no answer, leave a message & your # . He will get back to you. He sells only good, quality products! - F F

[rbone]

I agree with Ford Freak. While you can certainly try to rebuild it, excellent quality new ones are still readily available. It yours is frozen, it is likely pitted beyond repair anyway.

[aussie merc]

rust is the ultimate disaster for brakes as you have to remove so much material to remove the rust and retain a good concentric bore if a replacements availible take it it will cost less in the end and be a far better repair

[bergie]

Ordered a new master cylinder from Vanpelt today. Thanks for everyone’s input, BergieB.

[fortyfords]

Get in the habit of not pumping the M/C, just have someone push the pedal down while you open a bleeder. You must shut off the bleeder before he gets the pedal bottomed out but not a big deal. You will find that the brakes will bleed real easy this way.

[Fairlane514]

Master cylinder bore size can also be a factor, I assume you bought the same bore as original. It can effect pedal travel and effort with different bore sizes.

[aussie merc]

in reference to bore size the larger the bore the more fluid it will move but the trade off will be you need to put in a lot more pedal effort it also works in reverse smaller bore moves less fluid but lower pedal pressure

[glennpm]

Originally Posted by aussie merc

in reference to bore size the larger the bore the more fluid it will move but the trade off will be you need to put in a lot more pedal effort it also works in reverse smaller bore moves less fluid but lower pedal pressure

True but there are a couple of stepped bore master cylinders that will move a lot of fluid initially with a large bore and then reduce the bore for reduced pedal effort, Mico and Chevy Blazer for example:



https://www.mico.com/products/brake-...ster-cylinders


https://www.rockauto.com/en/moreinfo...68&cc=1060445&