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  View original topic: 1968 vw beetle woody brake bleeding
Mikhail_lewis Thu Nov 02, 2017 7:31 am

Ive primed the new master cylinder. Ive replaced brake pistons on all drums and installed new pads and new brake line hoses on the front.

I am getting very little liquid. I now started to get pressure on the actual brake pedal. I have pressure vacuum hand pump with bleeder kit. Me and my old man have been going at this for a while now on the driveway. And now it is -5 with lots of snow in calgary alberta.

What am i doing wrong? We had same problem on my last beetle 8 years ago. We eventually surrendered it to a shop and they got it done, but it took them a very long time too.

anyone local in calgary able to help out in cold weather? Od rather figure the problem out and how to do it myself for next time if anyone csn give me pointers... i want to drift my woody in the snow😍

sb001 Thu Nov 02, 2017 8:24 am

What order are you bleeding the brakes in?

Common practice is to bleed starting farthest away from MC and ending with closest. So this would be: Rear right, rear left, front right, front left.

Doing it another way may not be getting all the air out of the system.

bluebus86 Thu Nov 02, 2017 10:12 am

if fluid is not flowing well, it could be the four flexible hoses near each wheel have become internally restricted. what happens is just like what hallens with blood vessels, as the hose ages, the inside can clog, internally swelling, the exterior of the hose may all appear just fine, but inside is reduced to a pin hole diameter.
You may have to replace the hoses, they are a consumable item, after decades of use, they can fail like this.
remove a hose from the wheel that your not getting flow from, and look inside, can you easily pass a straightened coat hanger wire thru it with ease, can you easily blow air thru it? if not, replace all four, under the assumption that there are all the same age.

also you may wish to use the two person pump the peddle method of brake flushig, it is highly effective, and should eliminate the possibility of the power bleeder not working right. , maybe some thing is wrong with it?

anyway give the hoses consideration, as if they are restricted internally, they will produce the symptom you discribe.

good luck, stop sure,Bug On!

note with restricted hoses, they can sometimes act like a check valve, and result in dragging brakes when ylu step on the brakes, you develop high lressure which will force some fluid thru the restriction as the hose bulges, but when you release the peddle, the only force to send the fluid backwards to the master is the tiny springs in the brake drum, and they dont have near the force of your foot, so the fluid does not flow back, or flows back very slow, hence you brakes drag a bit. the hose kind of becomes a one way or check valve.
I have replaced clogged, restricted hkses that looked lerfectly fine on the outside, but had a massive restriction inside.


also a hint, use brake system compatible brake grease, or paste as it is sometimes called on the bleeder screw threads, tnis will help prevent them from rusting stuck for the next time you flush the brakes, this js the same brake system co parible grease you used on the piston rubber seals when you rebuilt the cylinders. but only ise grease or paste specified for use on brake rubber internal larts, other greases can ruin the rubber bits, even in trace amounts.


good luck, Bug On!

calvinater Thu Nov 02, 2017 3:04 pm

more pics of the woody please

vwoldbug Thu Nov 02, 2017 4:53 pm

You say new pads does it have disc brakes and how did you prime master cylinder

andk5591 Thu Nov 02, 2017 5:55 pm

Lets first get terminology straight to avoid confusion. Assuming you have drum brakes all around. If so, then the wheel cylinder is what actuates the brakes. Then you have brakes shoes and not pads.

You replaced the master, the wheel cylinders and the soft lines in the front. You bench bled the master.

First thing is to adjust the shoes to be dragging or some folks actually like to have them tight for bleeding. I bleed the fronts first, then the rears. Then go back around a couple times. You can use your vacuum pump to get fluid into the wheel cylinders, but I have never been able to completely bleed with it.

If you have a helper, use a hose and bottle with the bottle higher than the bleeder. Have them work the pedal 3 or 4 times, then push hard and hold it down. Crack the bleeder for a few seconds to get some fluid and hopefully air out (watch the hose for bubbles). Do that wheel until no more air. Check the reservoir fluid level and go to the next wheel until you go the whole way around. Readjust the brake shoes and go all around a couple more times.

heimlich Fri Nov 03, 2017 8:30 pm

I always use the two person method. I never bend bleed the master. I either start from the point furthest the master or the closest. Since I don't remember it must not really matter but the Bentley does tell you which is best.

I redid my rear brakes once and couldn't get all the air out. I found out I needed to replace the master. I replaced the master and tried to bleed my brakes and found out the rear cylinders I replaced pushed the pads to far out which caused them to stick which then caused the cylinders to protrude out and at an angle. This let air in and out of the system. Anything and everything is possible.

Divide the system into two, front and rear. Check if you can bleed the fronts. The go for the rears. If you can't bleed the rears start checking on that end. If it is the rear (or front) is this the end that you didn't change the tubes? Maybe they need it. Inspect them for rot and cracks. Even if there isn't any they may still be bad on the inside.

If it is the rears giving you problems pull the drum off and check the pads and cylinders. You have to rub a little grease on the inside where the pad hits. Take pictures of these areas and post them here so we can check if the springs/etc are correct.

Brian Fri Nov 03, 2017 9:25 pm

If it's a new master, triple check the pedal free play.

Mikhail_lewis Sat Nov 04, 2017 8:17 am

andk5591 wrote: Lets first get terminology straight to avoid confusion. Assuming you have drum brakes all around. If so, then the wheel cylinder is what actuates the brakes. Then you have brakes shoes and not pads.

You replaced the master, the wheel cylinders and the soft lines in the front. You bench bled the master.

First thing is to adjust the shoes to be dragging or some folks actually like to have them tight for bleeding. I bleed the fronts first, then the rears. Then go back around a couple times. You can use your vacuum pump to get fluid into the wheel cylinders, but I have never been able to completely bleed with it.

If you have a helper, use a hose and bottle with the bottle higher than the bleeder. Have them work the pedal 3 or 4 times, then push hard and hold it down. Crack the bleeder for a few seconds to get some fluid and hopefully air out (watch the hose for bubbles). Do that wheel until no more air. Check the reservoir fluid level and go to the next wheel until you go the whole way around. Readjust the brake shoes and go all around a couple more times.

Your terminology is correct. I have been doing it the way you describe for the most part. Will check shoes for how much drag is on them in the drum

andk5591 Sat Nov 04, 2017 11:28 am

Also - the post about pedal free play is VERY important. Pedal should move about 1/2" before you feel the pushrod hit the disc in the master.

Zundfolge1432 Sat Nov 04, 2017 2:16 pm

kawfee wrote: I always use the two person method. I never bend bleed the master. I either start from the point furthest the master or the closest. Since I don't remember it must not really matter but the Bentley does tell you which is best.

I redid my rear brakes once and couldn't get all the air out. I found out I needed to replace the master. I replaced the master and tried to bleed my brakes and found out the rear cylinders I replaced pushed the pads to far out which caused them to stick which then caused the cylinders to protrude out and at an angle. This let air in and out of the system. Anything and everything is possible.

Divide the system into two, front and rear. Check if you can bleed the fronts. The go for the rears. If you can't bleed the rears start checking on that end. If it is the rear (or front) is this the end that you didn't change the tubes? Maybe they need it. Inspect them for rot and cracks. Even if there isn't any they may still be bad on the inside.

If it is the rears giving you problems pull the drum off and check the pads and cylinders. You have to rub a little grease on the inside where the pad hits. Take pictures of these areas and post them here so we can check if the springs/etc are correct.

According to Bentley it matters. The single circuit thatís everything up to 66 starts from furthest working to nearest. Beginning in 67 U.S. models got dual relief and itís actually a good thing safety wise.

Dual relief starts with front passenger then driver then rear pass then driver side. Most often overlooked people ignore the flex lines and the free play adjustment at master cylinder.

As for bench bleeding itís not in the manual because it wasnít needed then, what were those stupid Germans thinking? :D

neil68 Sat Nov 04, 2017 11:30 pm

Zundfolge1432 wrote:
According to Bentley it matters. Beginning in 67 U.S. models got dual relief and itís actually a good thing safety wise. Dual relief starts with front passenger then driver then rear pass then driver side. As for bench bleeding itís not in the manual because it wasnít needed then, what were those stupid Germans thinking? :D

Ditto. I follow the Bentley manual as well, starting with front passenger, then front driver, rear passenger, rear driver. Bench bleeding is not needed if you have the stock fluid reservoir up beside the speedo.

andk5591 Sun Nov 05, 2017 11:04 am

neil68 wrote: Zundfolge1432 wrote:
According to Bentley it matters. Beginning in 67 U.S. models got dual relief and itís actually a good thing safety wise. Dual relief starts with front passenger then driver then rear pass then driver side. As for bench bleeding itís not in the manual because it wasnít needed then, what were those stupid Germans thinking? :D

Ditto. I follow the Bentley manual as well, starting with front passenger, then front driver, rear passenger, rear driver. Bench bleeding is not needed if you have the stock fluid reservoir up beside the speedo.

Have never bench bled a master..never had the need. And FYI - I broke down and bought a Motive Power Bleeder recently ad just used it yesterday when I replaced a leaking wheel cylinder. I think I am gonna like it.



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