Brakes, my dilemma, need advice

[DaVonZip]

I've put in many new master cylinders over the years, without any real issues. Lucky i guess... but i just changed the master cylinder, drums, brakes, wheel cylinders, bearings, . on my 71 Super. (not the hoses)

Problem: Keep getting air when bleeding drivers side rear line.

This line, on every opening, first thing out is a pocket of small bubbles THEN fluid, every time, not fluid then bubbles, but a pocket of tiny bubbles then fluid.

Logically, if the other three lines bleed nicely, and this line has this symptom, the problem should be confined to that area. Either the wheel cylinder is bad (no signs of it) or the hose is bad. Am i on the right track?

I have checked everything two or three times, brake adjustment, leaks, peddle distance, pushrod distance..everything.

My plan: replace wheel cylinder first, see if works, then hoses, see if works, then another master cylinder, see if works, if not, slowly roll car down hill towards awaiting lake

Thanks for any input.
Rick
_________________
-No, the point is, it's your frickin car. Drive it. park it, light the bitch on fire-- it's not for us to say. (samba member)

-For once in my life, i'd like to get up in the morning and be as happy as my pennis is... (samba member)

[DeathTrap]

beyond the fact you see bubbles,

Do the brakes work?

Does the peddle have any pressure behind it, or just go to floor?

If you "pump" the peddle does it after a few time hold pressure?

If so adjust the brake shoes.

Adjust the shoes. Adjust so tight it fully stops the wheel from turning, then back the adjuster off just three clicks.

Do all four wheels.
with a test drive between adjusting sessions
then do it all over again till the brakes work just like normal

It can take a couple few times till you get them adjusted.

[vernonc]

Perhaps the 'bleeder screw' on that wheel cylinder is not fully shutting off and allowing air to be suck back in. Just a thought.

By the way, if the rubber lines haven't been changed in a while, I would change them........especially since everything else is new.

Hope you find your problem.

mort
_________________
"Those who don't read newspapers are un-informed. Those who do read newspapers are mis-informed." Will Rogers

'69 sedan, low mileage, all original.....currently being 'freshened-up' for road trips and daily driving...just not every day

Freshening-up link http://www.thesamba.com/vw/forum/viewtopic.php?t=617386

[Cusser]

[DeathTrap]

Or the bleeder screw in that wheel cyl fits loose giving the phantom bubbles past the threads.

Chances are it's bled well enough.
Or at least as well as can be done with the shoes a mile out of adjustment.

Adjust the brakes. As tight as can be and as many times as required.

then adjust everytime the pedal gets past halfway. Or 3/4 travel. or second or third pump.

Or just keep bleeding and replacing parts.

Many times these cars get parked for no brakes when all they needed was adjustments.

[pistolpetecowboy]

You can try grease or Vaseline all over the bleeder and its threads next time you bleed that wheel cylinder.
If that eliminates your bubbles it's just phantom bubbles via the bleeder screw threads.
_________________
70 Beetle, 70 Beetle, 71 Beetle, 71 Super, 73 Super, 74 Beetle, 2000 Vintage Speedster, 2020 Jeep Renegade, 71 Squareback

[DaVonZip]

Like i said, been here, done that, this is not my first rodeo

Pedal is not just like mush but almost none existent..to the floor
I have adjusted and re-adjusted the brakes, they are all a few clicks away from the drums.
I changed out the wheel cylinder on the one that wouldn't bleed right. The burst of small bubbles at every turn disappeared. This got me really excited thinking i found the problem..but she still puts out air and wont stop, used a bottle and a half of fluid. So frustrating...
Waiting on rubber brake hoses now to see if this helps,
Thanks for input guys,
_________________
-No, the point is, it's your frickin car. Drive it. park it, light the bitch on fire-- it's not for us to say. (samba member)

-For once in my life, i'd like to get up in the morning and be as happy as my pennis is... (samba member)

[DeathTrap]

A few clicks from the drum?

they need to be a few clicks from locked up with so much drag it's near impossible to discern the second shoe's desired locking point.

Once around the block they'll free up fine.

My professionally experienced opinion.

and it might take a second adjustment again after the trip around the block to attain a full pedal.

[Cusser]

[DaVonZip]

We adjusted brakes so the drums dont move, started bleeding brakes (with partner),
We can get the back to bleed and get a strong pedal, then we do the front and the pedal goes limp and down to the floor, everytime! The front bleeds just fine, one bubble and then solid.. I dont get it.?
have to bleed the front first and then back? I never had this problem before..
Any ideas appreciated

Rick
_________________
-No, the point is, it's your frickin car. Drive it. park it, light the bitch on fire-- it's not for us to say. (samba member)

-For once in my life, i'd like to get up in the morning and be as happy as my pennis is... (samba member)

[herbie13]

[modok]

There was a problem with some masters, where the rubber grommet on top (where fluid goes in) mostly blocked the drilling to let the fluid in.
They will work if pressure bled but not bleed right if you do it manually.

[DeathTrap]

Is it possible that the shoes have re-centered enough to cause excessive peddle travel once again.

Are they still adjusted tight?

Does the pedal hold firm then under light pressure fall? That would indicate a bad master cyl.

[Goldbug3318]