no pedal pressure on new brake job

boater

After installing news shoes, wheel cylinders, drums, lines and three master cylinders I have no brake pedal. I can see brake shoes moving very little on wheels but pedal goes to the floor. I have checked for leaks, I also bench bleed the master cylinder. I said three masters, replacing each one as I though that was the problem. Any ideas, I am doing something wrong but what? Restoring 1968 Beetle. Thanks

windfish · Posted: Mon Apr 21, 2014 12:34 pm Post subject:

Did you bleed each wheel cylinder as well? The lines must be purged of air.
Easier job with two people, one pumps the brake the other operates the little valve at each wheel cylinder. Keep the reservoir topped off with fluid or you'll have to start again, and make sure you have a fair amount of extra brake fluid.
Simple guide - http://www.vw-resource.com/bleed2.html

If you're trying to do that and get no pressure there's a problem with one of the fittings and/or the brake lines, look for the leak.

mrmdls · Posted: Mon Apr 21, 2014 2:06 pm Post subject:

I replaced all my brakes, hoses, wheel cylinders, and MC recently. The following may help you get your brakes adjusted. I used a couple things that I learned here:

1) When I adjusted my brake shoes, I tightened them till they were almost tight against drums.
2) I, then gravity bleed all the wheel cylinders. when doing so pay attention to the fluid in the reservoir. Just crack the bleeders one at a time, and let the brake fluid drain. I used half a jar of a baby food jar size.
3) Ensured that I had 8 inches between the firewall and the brake pedal, adjust as necessary.
4) Bled my brakes using a helper in the traditional method of bleeding brakes
beginning with the furthest back (rr, lr,rf,lf)
5) Backed my brake shoes off till there was just a little friction
6) Rechecked my brakes, and brake pressure
7) Adjusted parking brake

edit for spelling and edited for correction of distance

Juanito84 · Posted: Mon Apr 21, 2014 2:51 pm Post subject:

This seems to be a common problem. If you bleed and adjust enough eventually they will work.

In my experience first tightening the brake adjusters all the way to where you can't spin a wheel then having a friend pump as you bleed works best. That way you know the pedal slack is air, not a loose adjuster. When all bled and the pedal is hard then adjust the brakes until the just drag.
_________________
If a water cooled engine cools its water with air, isn't it just an overcomplicated air cooled engine?

[email protected] · Posted: Mon Apr 21, 2014 3:15 pm Post subject:

On a Standard beetle the front wheel cylinders are not set up so the bleed screw is at the top. The front wheel cylinder must be rotated 90 degrees to get that screw on top else there will always be air it there. I unscrew the backing plate and rotate it 90 degrees. Could also take the brake shoes off unbolt the wheel cylinder and hold it closed with a c-clamp while bleeding.

The Super does not have this issue.

DeathTrap · Posted: Mon Apr 21, 2014 3:26 pm Post subject:

go adjust them a bunch more times

sinch em up real tight

go mess with the pedal a few times and adjust them again

once you get the adjustment near right the pedal will appear

frequent adjustments are required

it's not a big deal if you own enough jacks stands to get it elevated

jwold · Posted: Mon Apr 21, 2014 3:58 pm Post subject:

I think the bentley says (depending on the year) to start bleeding with the right front, not the furthest away (right rear).

This helped me get pressure started, but I still went around and around for a while.

Takes time, I gravity bled mine as well.

Q-Dog · Posted: Mon Apr 21, 2014 6:54 pm Post subject:

In my experience, most of the time a low pedal problem is a result of the shoes not being adjusted tight enough.

I have done a lot of brakes and master cylinders and I have NEVER removed a backing plate to bleed brakes on a beetle, and I don't gravity bleed, or vacuum bleed, or power bleed. Simple 2-man pump and bleed ... one wheel at a time with the shoes tight. All that other stuff just isn't necessary.
_________________
Brian

'69 Dune Buggy
'69 Beetle Convertible
'70 Beetle

Juanito84 · Posted: Mon Apr 21, 2014 7:03 pm Post subject:

BugMan114 · Posted: Mon Apr 21, 2014 7:05 pm Post subject:

people love to overcomplicate brake bleeding, XD. have a friend pump the brakes, and hold it down. loosen the bleeder to let some fluid shoot out, and tighten back up. repeat till no air comes out. start at the farthest wheel from the mastercylinder, and finish at the closest. Then you have to adjust all 8 shoes. this is the biggest pain in the ass, main reason why I switched to 4 wheel discs Laughing

_________________
1974 Super Beetle: Custom resto in progress
1972 Super Beetle: Daily Driver
1971 Std. Beetle w/ 1929 Mercedes Benz Gazelle kit
1960 Baja Bug
1969 Baja Bug
Sand Rail- Homemade
Sand Rail- FUBAR

Aircooled Airheads

Why the hell do they call it a gland nut. its obviously a big fat bolt!!!

boater · Posted: Tue Apr 22, 2014 5:12 am Post subject:

Thank you all for good input. Will work on car today and get back with results. Thanks again !

brendo907 · Posted: Thu Apr 24, 2014 5:17 am Post subject:

im glad i read this, sounds alot like my brake job. I have to pump once to get decent pedal. I guess ill be tightening my brakes and bothering the lady tommorow

boater · Posted: Mon Apr 28, 2014 5:46 am Post subject:

worked on car last weekend. Went over everything. All parts brand new. Still no brake pedal . I'm thinking as the car sat for about a year with all parts installed in garage, system could have become dirty. I'm tear down all four wheels and clean and reinstall. I agree installing brakes and bleeding is not rocket science. Must be overlooking something. Will be trying til I get it right !

brendo907 · Posted: Mon Apr 28, 2014 9:36 am Post subject:

Allyn132 · Posted: Mon Apr 28, 2014 9:42 am Post subject: Bench bleed

You MUST bench bleed the Master Cylinder, otherwise you will get the results you are getting. Bench bleeding requires the use of plastic temporary plugs and a little patience. But you will get the desired result.

Allyn

zombiebug · Posted: Mon Apr 28, 2014 11:04 am Post subject:

Are you losing fluid? Is it possible your brake line to the rear has a leak in the tunnel causing you not to see it but giving you the impression its the parts?
_________________
'74 Super

boater · Posted: Tue Apr 29, 2014 4:57 am Post subject:

Yes, after pumping pedal, still no pressure. As the car was sitting, I changed all brake lines. Positive no leaks. I leaning toward the fact that I am not bench bleeding Master cylinder correctly. Will try again ! Thanks for all input.

Batan · Posted: Tue Apr 29, 2014 5:11 am Post subject:

I bled, bled, bled, bled and bled brakes on my Ghia one time after replacing a bunch of brake parts. Everybody was telling me to bench bleed, to do this and that. I did. No go.
In the end, it was a brand new MC that was faulty. I put in the old one and finished everything in 15 minutes.
Other than that one, I never bench bled a MC , never had a problem with pedal pressure. One time I did was a bad part.
_________________
'69 Riviera Bay
'03 20th Anniversary GTI
'74 Super Beetle
Badzak Creative – Still and Motion Pictures

Q-Dog · Posted: Tue Apr 29, 2014 7:31 am Post subject:

Bench bleeding is not necessary, but it will tell you if the Master Cylinder is good or bad.
_________________
Brian

'69 Dune Buggy
'69 Beetle Convertible
'70 Beetle

DeathTrap


Hello! Log in or Register \| Help \| Donate \| Buy Shirts	See all banner ads \| Advertise on TheSamba.com

Forum Index -> Beetle - Late Model/Super - 1968-up		Share:
		Print View

	Forum Index -> Beetle - Late Model/Super - 1968-up	All times are Mountain Standard Time/Pacific Daylight Savings Time Page: 1, 2, 3, 4 Next
Page 1 of 4