This information was provided in another thread that was covering several topics. It was suggested that it be split out into a new thread as it may be beneficial to others as well.

Bleeding A Hydrovac Brake System, Manual
Manual bleeding requires filling the master cylinder reservoir and pumping the brake pedal to force the fluid through the lines to expel air from the system. This operation must be done with the engine shut off and no vacuum in the power brake system.

With the master cylinder reservoir filled, open No.1 bleed screw on the Hydrovac and depress the brake pedal to expel air. When the brake pedal has reached the toe board, close the bleed screw before returning pedal to release position. Repeat this procedure until soild fluid, free from bubbles, comes from the bleed screw. Check the master cylinder frequently to insure an ample supply of fluid.
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Using this method, bleed No.1 and No.2 bleed screws on the Hydrovac and then proceed to the vehicle wheel cylinders. Then start with the wheel cylinder farthest from the master cyl and work your way to the wheel that's closest; typically Rr, Lr, Rf, Lf.

 

Thanks for posting this!

 

Does a vacuum pump/one man bleeder work with this contraption? I'm too lazy to get someone else to help.

 

I have never been able to properly bleed a systen with a remote booster with a vacuum bleeder.

If you have no pedal at all, I suggest doing a part by part test -
1 - remove brake line at master cyl and plug master cyl. If pedal is good, master cyl is good.
2 - Reconnect master cyl, ans disconnect the lines to all wheel cylinders from remote booster, plug remote booster. Bleed remote booster and then check pedal, if it is good remote booster is good.
3 - Reconnect front brakes, plug/cap lines to rear brakes. Bleed front brakes. Check pedal, if it is good, front brakes are OK.
4 - Reconnect rear brakes, and bleed them. For dual cylinder brakes I have found that you need a helper who can really apply the brakes hard. Make sure you open the bleeders as much as possible to get a strong stream. If the wheel cylinders are good, this should result in a good pedal. You may then want to rebleed the fronts to make sure all air is removed.

If you start with a "pedal to the floor" and a simple bleed has no effect, I have found that the above procedure and a helper is the only way to go. Good luck.

 

sweet! this is going to help me bleed the brakes on the bronco/f800 as soon as i get it back from storage!! i was wondering what the procedure was going to be.

 

Really, Thank You for posting this.

 

This post is a life saver, thanks!!!!!!!

 

Pressure bleeder is the appropriate tool.

 

thanks for this post working on a 1975 f600 with no brakes ill give this a try

 

If any of the wheel cylinders are not fully horizontally mounted (at an angle or fully vertical), I recently discovered that backing off the brake shoes helps eliminate the air pockets that form above the bleeder screws.

Just be cautious in how far you back them off (if star wheels - cam adjusters can be backed off all the way) - I backed one off too much and it started leaking when I started bleeding them. I would guess only backing them off enough to remove the drum is good, but I haven’t had the chance to experiment.

 

thanks for the advice ill back mine off before i start this type system is all new to me will a vacuum bleeder do any good on this type brake system

 

I don’t know for sure, but I’m guessing the lines are just too large and too long for a vacuum bleeder to be effective. Vacuum bleeding depends on moving the right amount of air volume for the right amount of time and most commercially available vac bleeder kits just aren’t capable of doing it. I suppose if you have an electric vac pump it might work, but the problem with that is you’ll never see air stop moving thru the line because it’ll siphon air from around the threads of the bleeder screw.

If you don’t have a pressure bleeder, I’d recommend gravity bleeding to start, just to get some fluid in the lines, then manual bleeding with a helper to make sure it’s all purged.

 

Does anyone know the part number for the hose from the master cylinder on this set up? Need to replace mine as it has a compression fitting that shouldn't be there in it.
Thanks
Erik

 

thanks DBGrif91 ill check on a pressure bleeder and do a gravity bleed first and go from there thanks again

 

I've got a 78 f600 and the bleeders look different than the standard 7/16 " ones I grabbed at the parts store, is there a particular name for them? having a hard time finding them
thanks