Brake problem

MattB · « **on:** December 05, 2008, 07:35:46 AM »

I've been trying to get the brakes working on my 73 standard bug for several weeks now, but with no luck.

When I bought it the back brakes didn't work at all. The guy I bought it from said he replaced the master already. I took all the hoses & pipes off the back and they were gunked up with rust, so I cleaned the metal hoses and replaced the rubber hoses all round. Put new shoes on the back (fronts were fine), adjusted all round and tried to bleed the system using the pedal up/down method. This was partially successful but the pedal would still go right to the floor with little braking.

Assuming the master cylinder was bad, I bought a new one (from Mainly Foreign), had it bench bled and fitted it. Tried to bleed the system again but had the same problem - pedal goes all the way to the floor.

I took it to a brake shop and they fought with it for a while but couldn't get it any better. They said that when they were bleeding with a handheld vacuum pump they heard a hissing noise coming from the rear brakes, so the cylinders are probably bad. I replaced the cylinders all round last night (again decent ones from Mainly Foreign), attempted to bleed again but still the pedal is going to the floor. If I put a handheld vacuum pump on either rear brake and pump, the pressure goes up as I pump but I don't get any fluid or air out. Having a willing assistant pump the pedal whilst I open/close the bleed valves only pumps a small amount of fluid/air out. The pushrod has about 2cm clearance (I increased it by moving the pedal stop to make sure the compensation ports were being properly opened).

Do handhled vacuum pumps work OK on bugs? Is there anything else I should be looking at? This car's killing me!

Thanks!

Ret.Bugtech · « **Reply #1 on:** December 05, 2008, 09:04:19 AM »

Interesting. When you say you cleaned out the metal lines, does this mean you included the front to rear metal line ? This line will most of the time rust out and not stop up though. I,m assuming that you are getting fluid to the master cly.
When I was with VW , they told us to bleed the double master cly. starting with the right front,left front, right rear then left rear although I find it strange that you cannot get any fluid out using a pump.
If your pedal is going clear to the floor board tells me that you have no brakes at all.
Zen made a pressure pump that he screws on the top of the fluid reservoir and puts a SMALL amount of pressure on the system and then opens a bleeder valve.
I would do this, adjust all your brake shoes up to where they drag pretty good and then using the pedal pump routine starting with the right front as stated above and see what happens. Keep a eye on the reservoir . If the fluid goes down and still no rear brakes, pick you floor mat up and see if you have a gallon of brake fluid under there along the tunnel front to rear.

ASBug · « **Reply #2 on:** December 05, 2008, 09:09:57 AM »

Matt,
Had this same thing with the '72 Autostick Bug (ASBug). The trick was to jack up the car's front, run the adjusters out all the way (a little on each alternating-you did put anti sieze didnt you...) untill the wheel WILL NOT TURN. Then go in the car and push HARD on the peedle. You'll know what I mean. Then get out and majicly the wheel will be loose again, really loose. Do the same over again untill pushing the pedle hard has no effect on releasing the wheel. Then back out the 2 adjusters the same amount to barely get a brake drag when you rotate the wheel. Then move to the other front wheel, and repete. If you have both the front wheels off the ground, USE JACKSTANDS - not cinderblocks, you can compaire the two finished wheels together for drag. Move to the rear and repeate. You may have to "back off" a wheel once you drive it a day or so... I had to as the passenger's wheel stopped with more force than the driver's front and would pull to the right when you braked hard.

I hope that this made sence.
If you are relying on the bleed technique, you'll never have good brakes. I drove the ASBug with the is STOMP and PRAY brakes with all new components for a bout 2 days, then I got with either ZEN or DAVID to learn this tidbit of knowledge....
Thanks & good luck:
KC

MattB · « **Reply #3 on:** December 05, 2008, 12:11:24 PM »

Thanks for the great advice, I'll get back into battle this weekend and see what happens.

I cleared out all metal lines apart from the long front-back line, However, I did disconnect it from the union at the back, had someone press the pedal and lots of fluid came out, so fluid flows through pretty well. I'm also going to recheck the back metal and rubber lines to make sure they haven't got gunked up again.

Thanks again, will let you know how it goes!!

BTW, the order confuses me a little. Bentley and you guys say FR, FL, RR, RL. Haynes says RR, RL, FR, FL. Some more generic sites agree with Haynes, in that you start with the brake that's got the longest line from the cylinder which makes more sense to me. Any ideas why VW recommend their order?

Ret.Bugtech · « **Reply #4 on:** December 05, 2008, 12:42:53 PM »

The longest line bleed was for single stage only. The RF,LF, RR, LR method came from VW as gospel in the form of a shop bullitin. You can bleed anyway you want ,but it takes forever to do it. Its the way VW built the cly. There is no mechanical connection between the 2 pistons so you have to have pressure up on the front brakes to let the rear piston have something to "lean" on to build rear pressure. It just take much less time to bleed the system. I hope that explains it.

virgo062 · « **Reply #5 on:** December 05, 2008, 04:16:46 PM »

I paid $300.00 a few months ago for brakes on my 71 super and when I got home I had some brakes but not enough to suit me. Whilst replacing the floor pans we found the main line front to back had been leaking a long time so we replaced that, this time NO BRAKES. We tried every trick on this site and nothing worked. We called Mainley dude there told us there was a problem with the Master Cylinders he was selling so he replaced ours but we have not had a chance to replace it. But that's the least of my problems with FeeBee right now. Because if it won't run you don't have to worry about stopping now do ya :lol:

MattB · « **Reply #6 on:** December 05, 2008, 04:21:34 PM »

Did he say what was wrong with the cylinders & if they fixed them? I'll be pretty annoyed if he sold me a bad one!!

virgo062 · « **Reply #7 on:** December 05, 2008, 04:27:00 PM »

He just said they were bad and he was replacing them. By that time we were so annoyed about everthing else I guess we let the Master Cylinder get a pass even though we spent 5 days trying to get brakes. Like I said we have not had a chance to put the replacement on so who knows.........

Bugnut · « **Reply #8 on:** December 05, 2008, 08:02:30 PM »

It's not uncommon to get a bad one from time to time....it happens. :oops:

Zen · « **Reply #9 on:** December 05, 2008, 11:28:55 PM »

Quote from: "MattB"

Do handheld vacuum pumps work OK on bugs?

I bought one and after a couple of hours of trying to bleed the brakes on a bug, I tossed it across the yard. 6 months later, I dug it out of a pile of leaves, cleaned it up and used it to bleed the brakes on a bug . . . but as a pressure pump, not as a vacuum pump (mine had a vacuum port and a pressure port). They are the perfect pump for pressure bleeding (at least the one I had was) because they won't pump much pressure. All you need to do is get an extra fluid reservior cap and rig a way to seal it to the reservior and pump air through it. I did this by cutting a circle of flat rubber to fit inside the cap for a seal, then drilling a hole in the center of it. I pressed an old valve stem into the hole, took the core out of the stem and stretched the hose from the pump over the end of the valve stem. It works best if you have one person watching the fluid level and keeping just a little pressure on the reservior and one person running around the car opening and closing the bleeders. Open a bleeder (any bleeder . . . it doesn't really matter what order you go in for pressure bleeding) and let the fluid flow. Keep it flowing until it comes out clean and without any air in it, then move to another bleeder and repeat. I've tried to bled brakes by every method know to man . . . pressure bleeding is the ONLY way to do it.

Ret.Bugtech · « **Reply #10 on:** December 06, 2008, 10:58:06 AM »

I agree with Zen on the PRESSURE pump. If you don't want to make yourself a pump, use the VW plan. I have a pressure pump and it allows me to bleed brakes solo if I put a hose on the bleeder valve and stick it a bottle with some fluid in it.
Ing.timing and brake work seems to the most F.A.Q.

Zen · « **Reply #11 on:** December 06, 2008, 11:44:20 AM »

Quote from: "Ret.Bugtech"

Ing.timing and brake work seems to the most F.A.Q.

:-k What if a person with formal training and lots of hands on experiance were to write a book that anwered all those F.A.Q.s in language a VW newbie could understand . . . Kind'a like the "Idiot Book" only written by a "real" mechanic and ilistrated with boring (but real life) photographs instead of cool artwork . . . Think it would sell? I do. I'd buy a copy. Maybe two copies.

David, you know you wouldn't have to do much typing if you wanted to write it . . . you could cut and paste most of the book from stuff you've already written in the slow starter thread! What do you think?

MattB · « **Reply #12 on:** December 06, 2008, 06:06:11 PM »

Thanks again for all your advice.. Here's where I'm at.

I jammed up the front brakes using the adjusters, got someone to press the pedal whilst I tried to bleed but virtually nothing came out even though the pedal went all the way down. Time to get rid of that new master cylinder. I put the previous cylinder back on (was told it was brand new anyway), and during fitting noticed that the brake pedal was going all the way down and actually stopping when it hit the metal of the frame. Consulting my trusty Bentley manual (which these days is starting to look very well used!), it looks like the pushrod length has been modified. I readjusted everything as Mr Bentley says and now the pedal stops at the end of the cylinder, not on the car frame.

So, connected everythinng back up again, bleeding went much more successful. Lots of air/fluid came out when the wife was pressing the pedal. I bled the front til no air, then bled the back til no air. I went back to the front, and a good amount of air came out again. I did the back and some more air came out. I kept going from front to back but there was always a little bit of air.

Taking it out on a road test, the car does stop now (hurrah!) but the pedal goes a long way before this happens. If I drive with the handbrake up a bit, the pedal works higher up.

I have two theories now...

1) There's just lots of air in the system, I need to keep bleeding front/back for a long time! Or get a pressure bleeder (might just take some beer to the brake shop down the road and ask nicely... getting fed
up of crawling round under a car in near-freeing temperatures)

2) There's a leak somewhere that is causing air to enter the system. The rubber hoses are new, cylinders are new and I'm positive that on the front all the connections are nice and tight. I haven't double-checked the back yet, but the front is easier to work on and as I understand, air from one system shouldn't enter the other.

Any other advice before I take it to the shop? Or even any recommendations for a garage that know these things well?!

Thx again!

virgo062 · « **Reply #13 on:** December 22, 2008, 03:01:09 PM »

Hey MattB we finally got tired of messing with FeeBee's brakes and hauled her off to be Ricks problem for awhile and guess what? Number Two MC was bad as well. I can understand getting one bad one but TWO. Anyway that's my story and I'm sticking to it :twisted: And Zen I would be first in line to purchase VW repairs for Dummies as long as the names were changed to protect the innocent :lol:

Ret.Bugtech · « **Reply #14 on:** December 22, 2008, 04:31:31 PM »

Innocent

Right !! I would be curious what brand these bad M/C are.
I got Alberts M/C from Al Johnson VW in Dalton. One brand I have used for years was a VARGA (that I didn't have any trouble with at all )when I couldn't find a ATE. (OEM)
If I write a "book" , no one will be safe ,me included :shock: :oops: :lol:

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