Back Drum Brakes Will Not Bleed

[Ben Kennard]

I have front discs with rear drums on a 70 satellite and cannot get fluid to the rear drums. I cracked the t valve and still no fluid. I checked the inline hold off valve and had fluid to that point but after several pumps of the pedal, my fluid in the mc is still the same. What is causing it seems like no fluid pressure to the back?

 

[Photon440]

Try putting a vacuum bleeder on the rear brake cylinders and see if they can pull any fluid through.

 

[Ben Kennard]

Will keep that in mind. Could it be the switch on the distribution block? Does this change the amount of fluid to the rear of if the fronts are already bled?

 

[NJRR]

If you suspect the distribution block, disconnect the line out to the rear and give the pedal a pump. If no fluid comes out, disconnect the rear line into the distribution block. If no fluid comes out, disconnect the rear line out at the master cylinder.
If no fluid comes out of the master, that's your problem. It's really a matter of process of elimination.

 

[miller]

My disc/drum brakes were like that, no fluid to the rear. The rear block, where the lines split, was clogged.

 

[rlem1977]

When bleeding the brakes, the PV should be blocked off to prevent it from moving. Could be it's blocking rear brake actuation and needs to be re-centered. Or as others have stated, there is another blockage somewhere. Just me, I don't like 48 year old brake parts. I'd make sure the lines, hoses, tees, etc. are new(er).

 

[oldbee]

When bleeding the brakes, the PV should be blocked off to prevent it from moving. Could be it's blocking rear brake actuation and needs to be re-centered. Or as others have stated, there is another blockage somewhere. Just me, I don't like 48 year old brake parts. I'd make sure the lines, hoses, tees, etc. are new(er).

Same thought, maybe the shuttle(?) valve is stuck blocking off the rear line, usually when manual bleeding you never bottom out the brake pedal because that will move that valve because it thinks there’s a leak.

 

[Ben Kennard]

rlem1977 and oldbee; I had my partner pressing the pedal and I know he went to the floor. Everything line and valve wise is new. I am going to try and break the bleeder valve on the right front and barely press the pedal and see if I can get the valve back to neutral. Does that sound like the right procedure to get the valve back to center?

 

[oldbee]

Yup, fingers crossed! Used to never go over 3/4 pedal travel(less is better).

 

[incinr8]

I couldnt get my rears to bleed. it ended up being the rubber flew hose that had broken down and clogged..