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Bleeding brakes but still soft!
Bertie_64 - January 20th, 2007 at 08:33 PM

Just finished bleeding brakes in my 71 bug and they are still soft. Tried everything but it feels like there is still air in it. Have overhauled master cylinder and rear wheel cylinders. The pedal is solid but there is still a lot of travel. Have also adjusted the rod. Has anybody else had any problems? Is there a way to fix it?


Grey 57 - January 20th, 2007 at 08:36 PM

Have you adjusted the rear brakes??


Bertie_64 - January 20th, 2007 at 08:38 PM

Yes I have


Grey 57 - January 20th, 2007 at 08:53 PM

hmmmm ok. Might be a pressure bleed job. Can you have someone pump the pedal and hold pressure while you release the bleeder??.


urban_myth - January 20th, 2007 at 11:32 PM

check the rubber hoses in your brake lines. one of them may be old and expanding whenever pressure is applied


ExQuokka - January 21st, 2007 at 07:59 AM

Did you replace the fluid? An air bubble is the most likely cause, but sometimes really old fluid can become unuseable. After that you may need to look at the master cylinder - are you losing any fluid?


geodon - January 30th, 2007 at 04:01 PM

If ur still in trouble, I have removed stubborn bubbles by working backwards. Get a disposable 50ml syringe wo the needle from ur local pharmacy. The thin hose from the dist vacuum should fit on the respective ends of the syr & the bleed nipple or use a plastic one. Then instead of pressure bleeding bubbles out they can be sucked out by loosening the nipple & pulling the piston of the syringe out. Then close the nipple b4 taking the hose off. Repeat if necessary.


1500S - January 30th, 2007 at 04:12 PM

Make sure the hand brake is backed off before adjustment. One major source of excess travel if it has been adjusted over time and is pulling the shoes away from the pistons.

DH


greedy53 - January 30th, 2007 at 05:44 PM

master cylender may be seeping back


68AutoBug - January 30th, 2007 at 09:20 PM

I used about 3-4 bottles of brake fluid doing My brakes after replacing everything including all hoses...

I was told by a brake mechanic to jack the rear up so the rear brake bleeders are above the master cylinder..
undo the bleed nipples and go and have a cup of coffee..
or lunch... the air should be bled out by then..
just make sure the brake fluid doesn't empty out of the brake fliud container...

also, take the brake light switches out to see if any air is trapped in them....

having all these problems is VERY common....

Lee


1500S - January 30th, 2007 at 10:36 PM

Have seen a number of VWs over the years with this problem and it's mostly been the handbrake causing the problem as I've said above. It doesn't take much clearance on the pistons to give excessive pedal movement. If there is any tension in the cables it is pulling the shoes away from the pistons. Loosen the cables, adjust shoes and then adjust cables last.

DH