Brakes - 71 std. have done everything

[andk5591]

Spending way too much time on this..And it aint my first rodeo.

71 Standard.
All new metal lines except at the rear
3 new soft hoses...Drivers side front looks like it has been replaced recently.
New master
Using power bleeder and flushed at least 1 quart through it so far.

Initial complaint from customer - brakes were mushy and just didnt feel right. He had already replaced the front wheel cylinders and soft lines. The main line to the rear had a coupler. We replaced the entire line. He also wanted the master replaced since he suspected it being the problem.

We had good pedal and were ready to send the car home. Just wanted to double check the brake light. Pedal went to the floor. Used power bleeder and conventional bleeding. Got mushy pedal and if you stayed on it, gradually went to floor. Air in the lines, right? more bleeding (yeah the shoes were adjusted snug - slight drag. No air, no improvement.

At this point I am suspecting wheel cylinder...So, I do this as last resort. Line clamp - one wheel at a time and see if things change. Passenger front clamped got firm pedal. OK, gonna replace the hose AND the wheel cylinder. No improvement, but now no change when clamped.

Ok - lets try clamping the other wheels - No change. But as I was going through another bleeding, saw the hoses at the rear leaking - not surprised. They were older and the clamping damaged them. OK replaced those. Doing visuals for leaks...nothing else.

BUT then the during bleeding, felt like the piston stuck in the master...OK This was an off the shelf master I had. Carquest low end part. Swapped with a World Products (or whatever they are called) master. Still spongy pedal..... Enough for one day.

Plan for the morning is to put a container at each wheel and pump up the power bleeder and run a quart of fluid through the whole system at one time. Any other ideas would be welcome..
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them...

[VW_Jimbo]

Take a threaded plug, threaded like the flared nuts on the line into the master. Thread 3 of them in place of the lines. Bleed the master. Have someone pump up the pressure, hold their foot on the pedal, as you loosen the previously installed nuts.


Does the master hold pressure?

No, replace master. Bleed. Retest.
Yes, attach one front and bleed. Hold pressure?

No, replace wheel cylinder or hose or both and retest.
Yes, attach the other front and bleed. Hold pressure?

No, replace wheel cylinder or hose or both and retest.
Yes, attach the rear line and bleed. Hold pressure?

No, disconnect from wheel cylinder and cap. Bleed brakes.
Hold pressure?

No, replace T at line intersection or tighten fittings. Also replace hoses. Test again.
Yes, replace both wheel cylinders and retest.

If you go any further, you are on your own! Maybe get a different car, swap out parts and retest!
_________________
Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!

[joey1320]

[andk5591]

Liking this...Methodical....Thats essentially what I was trying to do with the clamping the line, BUT had to many potential variables doing one at a time. You are bringing them back in one at a time. Thanks
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them...

[VW_Jimbo]

Your welcome. Been down that road a few hundred times. I know it is not fun.
_________________
Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!

[busman78]

When you mentioned clamping the line did you clamp the soft line to each wheel cylinder? If you really did clamp them then you might as well replace them for clamping those hoses tight enough to stop the pressure either breaks the inner tube or separates it from the outer casing or both. Quickest way I know to ruin a brake hose beside cutting it with a razor blade.

[andk5591]

Gonna chalk this one up to I have no freaking clue. Decided to use my power bleeder as was designed. Filled it with fluid and pumped it up. Went through and bled one time. Good brakes. Solid pedal.

Doing another master tomorrow. Gonna just use the power bleeder from here on.
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them...