redoing brakes on 74 vw beetle have some issues

okay, this is on my moms 74 bug. so far we have rebuilt the wheel cyl's ... replaced all the pads and springs ... and have everything back together, the adjusters are turned to just where they drag on the drums ... the brakes have been blead (this is where the problem occurs) ...

the brake pedal goes completly to the floor ... and even pumping it doesn't build up a pedal ...

the resivoir is still full ...

if we take the top off of it, and pump the pedal ... in about 4 pumps it will build up some pressure (but the resivoir does not overflow) .. but put the top back on and you can not get any pressure built up at all ...

there are no leaks in the system .. and the soft lines are in good shape .. with no flexing or stretching when you apply the pedal

to me it seems that the master cyl is messed up ... with a possibility of an obstruction in the resivoir or the lines going from it to the master cyl...

any other tips or suggestions and such? ...

Reply to
Flea
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Is there some free play at the pedal? Push the pedal with fingers. It should move perhaps 1/4" before you feel the pushrod hit the piston.

Did you get fluid from each wheel cyl bleeder?

The reservoir cap has some vent holes; check that they are clear.

Speedy Jim

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Reply to
Speedy Jim

This is a long shot but on a few bugs I've had problems where the break lines to the real breaks held air in the loop over the rear wheels.

One solution was to lift/jack the rear end waaaay up in the air. The other was to use a vacuum to flush the lines clear of air (uses a lot of break fluid)

Reply to
NotMe

it moves about 1/4" before you can feel it engage .. but then it just keeps going till it bottoms out ...

got fluid from each cyl bleeder.

will have to check the reservoir cap to make sure those vent holes are clear...

Reply to
Flea

when i go back up there this wed to work on it again carrying my vacuum peice to flush all the fluid out and make sure there is no air anywhere in there...

Reply to
Flea

I can't remember where I read this, but the article said that vacuum is not the best way to do older model brakes. I use a power bleeder (postive pressure - 12lb). Had good luck with it.

Reply to
john

I have been saying that for a good while. The seals in the wheel cylinders are shaped to seal under pressure. The more pressure, the more the seal pre3sses against the cylinder wall. If you introduce vacuum instead of pressure, the seals actually seal LESS, and may let air in very easily.

We use a vacuum bleeder at work, only to flush the fluid. We don't bleed the brakes with it. In fact we gravity bleed or do it the old fashioned

2-guy way... one guy pumping the pedal and the other working the bleeder.

I have been talking to them about a pressure bleeder, but they don't see anything wrong with the way they are doing brakes now :)

Jan

Reply to
Jan

It's not like a pressure bleeder costs a lot of money. Maybe they can't learn the New Way (which is an old way). Bring one of those that you made yourself and make a killing on the flat-rate. They might understand the language of the big buck..

Say, Jan, how would you like to tear down a Raby engine to see what the hell's been wrong with it from day one and make it right. I'll write the book. You keep movie rights.

Reply to
john

I gave mine away when I moved... :( And I'm not sure I can make another $2 investment on specialty tools at this point. LOL

I don't have a shop and they won't let me work on my own projects at Firedstoned.. But I would love to take a peek for sure :) Email me some more details, symptoms, and a bottle of rum and I'll see if I can come up with some ideas.

Jan

Reply to
Jan

can't say i have ever heard of bleeding the brakes with pressure... will have to do a search

Reply to
Flea

It makes it so easy and fast you won't know what to do with all the spare time. One-man operation. Pressure to 12lbs. Bleed farthest wheel, next farthest, etc.. Fifteen minutes if you take your time.

Reply to
john

Where do you get these or where are directions to make one? Thanks, Andy

Reply to
Busman

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Reply to
Erik Dillenkofer

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Reply to
dave AKA vwdoc1

Cool. An easy project which does not take to long. Get a spare reservoir cap and modify accordingly. The catch bottle also needs a tiny vent hole drilled in the cap.

J.

Reply to
P.J.Berg

gravity bleeding has always been my prefered method.

Reply to
Joey Tribiani

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