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Sat Dec 08, 2007 9:40 am

Here's 3 topics worth reading:

http://www.thesamba.com/vw/forum/viewtopic.php?t=268316

http://www.thesamba.com/vw/forum/viewtopic.php?t=267509

http://www.thesamba.com/vw/forum/viewtopic.php?t=268167

Wed Dec 12, 2007 6:43 am

Thanks - I've bled brakes on several VWs but for some reason my 65 gave me the most trouble. And seems to give alot of others trouble seeing from all the brake posts.

I got mine all done last night - I had a faulty master cylinder. Scored a FAG MC here on samba classifieds for cheap. It took just two rounds on all the wheels but I bled at MC first and that really seems to help the speed up the process.

Mon Dec 17, 2007 8:32 pm

Yes its a labor intensive but the safety factor dictates that you go slow and ck everything twice ......... Most bleed problems are caused by not following proccess in order adjusting all shoes to slight drag then working from farthest to nearest wheel cylinder on the bleeding... Also newbies and a few not so newbies get all freaked out about altering the master cylinder push rod length .... Too much and you burn up the brakes not enough and you dont ever get all the air out, this is the gremlin that gets most of em as they read their little Bentley book and especially the section on never adjusting the pushrod length but if they read a little further Bentley also gives a dimension for this rod setting...... Next they go round and round trying to adapt American car techniques to this with their bench bleeding master cylinders and suction bleeders... I could show you VW repair shops that have done thousands of brake jobs over a span of 40 years never having used these worthless time wasting tricks.....

Years ago old Bob Hoover said it best when asked about suction bleeders for chevron type seals on the VW he said and I quote " the person buying the suction pump is the real sucker"... I suspect you'll keep seeing the same type posts about problems getting the air out especially as unscrupulous vendors keep selling suction bleeders that dont work..

Jim-

Tue Dec 18, 2007 2:55 am

Most lightplanes use disc brakes having O-rings instead of cheveron-type seals. Suction bleeders work okay with the O-rings.

As a point of interest the most common method used on school buses -- which have mandated brake maintenance & inspections -- is the old fashioned gravity-bleed, where the system is flushed & bled at the same time. This works okay for VW's but takes at least a quart of brake fluid; kinda expensive if you're using DOT 5.

Volkswagens have pretty good brakes. Simple to adjust (at least, on the early models :-) and simple to maintain. People who complain of poor braking with their Volkswagens usually have unrealized problems somewhere in the system, most likely due to internal rusting.

-Bob Hoover

Thu Dec 20, 2007 4:28 am

Don't forget to keep putting new fluid into that resevoir! And slowly too. Otherwise you'll make some bubbles in the fluid that's about to go down into your brake system.

In an ideal brake sytem there is no air. Your foot pushes the pedal which pushes the rod which pushes the fluid out against all four wheel cylinders. The wheel cylinders push the shoes. Our brake system is not really pressurized. That is until you push the rod across that 1mm of pushrod clearance.

It is pressure that transmits the force from rod to wheel cylinder through fluid. However when your pumping that blasted pedal you aren't trying to "build pressure." You are trying to move fluid which carries in it air bubbles which compress under that initial applied pressure. Once you've bled out the fluid with the enclosed air all that's left is fluid which will not compress but instead will faithfully transmit your applied force out to your wheels.

Sat Jan 05, 2008 9:29 pm

If you don't have that 1mm of pushrod clearance, then what do you do? I have a '62 with a dual circuit master in it, and I had to shorten my pushrod all the way, and It still has to be pushed in 'a little bit' before I can put the pin back in the brake pedal to secure it. I don't know why you'd leave that space, no matter how small as it's distance that your pedal moves without any effect on the cars braking.

Wed Jan 09, 2008 8:28 am

I got it fixed. I re-adjusted the pushrod, and the pedal stop plate to allow more pedal travel. They work great now. 3 rounds of bleeding and re-adjusting the pads, and I have a nice firm pedal with a short stroke.
I'm stoked..

Wed Jan 16, 2008 6:26 pm

Hey ive got a 66 and the brake line going to the resevoir is leaking it doesnt screw in it just sits there with a gromit any ideas?

Wed Jan 16, 2008 6:36 pm

what area is leaking? The connection by the resevoir, or by the grommet on the master???

Wed Jan 16, 2008 6:49 pm

the grommet to master ! and the rear driver side wheel cylinder which i have but really don want to buy a brake booster or dont think i need to if i can get the grommet to stop

Thu Jan 17, 2008 8:26 am

You can buy just the grommet.. However, if the grommet is leaking, it's probably time for a new master anyway.. If you are running the original single circuit, you should probably think about doing the dual circuit install with a volvo or rabbit resevoir. You should do the brakes once, and be done rather than piecing together one part at a time hoping that your parts don't fail in between. Do it once, and do it right, I guess that's just how I feel about it anyway.

Thu Jan 17, 2008 6:30 pm

i got a new grommet today the master cylinder looks new i agree with you though i went ahead and got thparts to do all four with new hardware wheel cylinders and all. so it looks like the grommet just pulls out and the new one in. i just got the car two days ago by the way all my prevous beetles had new brake stuff. if i were to replace the master with a 68 or so whould i have to put a threaded fitting on that brake line?

Thu Jan 17, 2008 8:18 pm

If you get the '67 or later dual circuit setup, you'll be having two lines running from your resevoir, unless you just use a 240 Volvo or rabbit resevoir mounted directly to the master.. Do a search, you'll find pictures of it. It's a safer setup, and all you have to really do extra, is put a second brake switch into the second fitting hole, or put a bolt and a ball bearing in there to ensure it doesn't leak. Good luck!

Fri Jan 18, 2008 8:20 pm

hey i replaced the grommit upon pulling it out it tore so i used a hook and got the rest of the grommet out now i tried to bleed it and the pedal just fallls to the floor should i just replace the mc like we talked about or is it something else? i also put new wheel cylinders and shoes in the rear.

Fri Jan 18, 2008 10:29 pm

Look around in some of the other forum threads on brakes, it can be a real pain in the ass, but be patient and take your time.. Or, you go to the dual circuit, and you'll have to bleed the system too... It's all trials, I just went through this 2 weeks ago..

Sat Jan 19, 2008 8:49 pm

i just did the shoes and rear wheel cylinders last night and the grommet but tried to bleed them and nothing the pedal just hits the floor? i have the adjusters on the shoes all the way in to put the drums on do u think that would have nething to do with it? now ebrake doesnt work either?????

Sun Jan 20, 2008 1:49 am

Zundfolge1432 wrote: Yes its a labor intensive but the safety factor dictates that you go slow and ck everything twice ......... Most bleed problems are caused by not following proccess in order adjusting all shoes to slight drag then working from farthest to nearest wheel cylinder on the bleeding... Also newbies and a few not so newbies get all freaked out about altering the master cylinder push rod length .... Too much and you burn up the brakes not enough and you dont ever get all the air out, this is the gremlin that gets most of em as they read their little Bentley book and especially the section on never adjusting the pushrod length but if they read a little further Bentley also gives a dimension for this rod setting...... Next they go round and round trying to adapt American car techniques to this with their bench bleeding master cylinders and suction bleeders... I could show you VW repair shops that have done thousands of brake jobs over a span of 40 years never having used these worthless time wasting tricks.....

Years ago old Bob Hoover said it best when asked about suction bleeders for chevron type seals on the VW he said and I quote " the person buying the suction pump is the real sucker"... I suspect you'll keep seeing the same type posts about problems getting the air out especially as unscrupulous vendors keep selling suction bleeders that dont work..

Jim- So what is with this bench bleeding you mention

Sun Jan 20, 2008 11:07 am

You need to adjust your brake shoes out all the way locked against your drums when bleeding.. You'll have to keep checking them, and once you are getting good fluid flow at the bleeders, and you have a good solid pedal, then you can back them off a bit until they are rubbing. Or, they may back themselves off a little, at least mine did..

Wed Jan 23, 2008 3:30 pm

so i still cant get them to work any ideas?

Wed Jan 23, 2008 3:47 pm

If you got a dual circuit master to replace your single, you may want to adjust your pedal stop at the pedal assembly. Ensure you have a long enough pedal stroke, and there is a measure of small space before the pushrod is supposed to engage the piston.. Check these in the forums, they are out there somewhere.. I had adjusted my pedals incorrectly, that was a problem for me, I just allowed for more pedal travel initially, and my brakes bled out perfectly, and have a short, firm pedal stroke now!
Good luck!