how to bleed brakes

I have a 1973 rr with manual front disc brakes, new calipers and front hoses, new master cylinder, new rear wheel cylinders, new flex hose at rear end,new brake shoes and pars. PROBLEM is brakes are bled and I still have to pump the pedal to stop the car. I can pump up a good firm pedal take my foot off and push down again and it goes to the floor. I have bleed every line and nut on system. any advice? Thanks Steve in Ga.

Needs to be bleed more and a pressure bleeder would be best if you know shop that could do that for you.

did you prop open the proportioning valve?

and then, bleeding is really a two person job. Someone needs to pump up and then lean on the pedal, you crack screw, and then tighten it back down while they're still on the pedal. repeat. start at rear, further wheel. then next rear wheel, etc

Did you bench bleed the master???

pump up the brakes & quickly measure the distance from the pedal to the floor then put a block of wood of that thickness there so you dont go past that travel range while bleeding. As said bleed the M/C first then I'd start on the front discs & I'd have your helper pump the pedal fast several times then you crack open the bleeder just as he is coming down on the 4th stroke which agitates the fluid & can help get the bubbles out & as you know close it before he lets up. On some cases you might have to remove the caliper & tilt it & the bleeder doesn't have to be exactly at 12 o'clock but where the bleeder passage meets the bore does & sometimes their a bit off & cant tell except for they wont bleed out.

As said did you bench bleed the master.Then make sure the calipers are mounted with the bleeders up.You can bleed all day if they arent.I know.Then start at pass rear.drivers R.Then pass frt and d frt.Dont push the pedal all the way to the floor.I have someone pupm a bit.Then just hold light pressure on the pedal.Open bleeder and push easy.Continue till no air at that bleeder then go to next.Ive had a few mostly Fords.That you need to open a frt bleeder and hit the brakes hard to reset the PP valve.If good fluid is coming out of the rears its usually reset.I also like to gravity bleed them first.After over 30 years as a pro wrench Ive seen and done just about it all. Rocky

Did you adjust the rear shoes? If they are way out of adjustment, that can cause the problem that you are experiencing. Good luck, Joel

Good point what Joel said. Pull on your E brake & You'll have the answer on that

If you don't want to buy a pressure bleeder, vacuum bleeder, etc. and don't have a helper handy, then a stick wedged betwen the seat and the pedal to hold it to the floor works well. pump the brakes with the rod, lock the pedal down with the wood. then go and crack open the bleeder, releive the pressure, seal the bleeder back up, and go remove the wood, allowing the pedal to return up.

repeat till pedal is rock hard.


as said, check your rear shoes make sure they're tight.

"bench bleed" the master. this can be done on the car too, crack the lines at the master the same as you do a bleeder screw at the wheel. just have rags to catch the drippings. This job may be best to do with 2 people regardless.

if that all fails...have you checked the clearance between the power booster and the master? (or are these standard brakes?) inside the booster, there is a little screw that you can adjust so that it's up against the master without actually pushing in on it.

my dad's van had this problem. he put a new booster on it, and while the brakes worked fine, the pedal felt spongy, and would go nearly to the floor before the brakes would react, but then they would put you through the windshield! it was difficult to "learn" how much slop was in the pedal, so that you could quickly push through it, without pushing so hard/fast that you activate the brakes like you were panic stopping.

I threaded that rod out 3 or 4 full turns for him, and now the brakes would activate as soon as you start to press on the pedal.

If everything is done right and pedal still goes to the floor and no leaks.You probally have a bad master.It happens.I always use 70 C body master when I do a conversion.Rocky

lots of good advise, you could also try clamping off one brake hose at a time to isolate the problem too...