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Brezelfahrer Samba Member
Joined: March 26, 2010 Posts: 65 Location: Vlaanderen
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Posted: Tue Jun 14, 2016 1:06 am Post subject: Unusual brake wear |
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Hello everyone
yesterday I was restoring the rear brakes on my european standard.
At first all linings seemed to be fine, but then I saw this unusual wear on one side underneath. The lining was almost completely worn.
Was it a bad assembly or what?
Just to avoid the same mistake as I want to obtain the best brakeperformance _________________ 1952 typ 1 european standard
1959 typ 1 european standard sunroof |
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johnshenry Samba Member
Joined: September 21, 2001 Posts: 9359 Location: Northwood, NH USA
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Posted: Tue Jun 14, 2016 1:13 pm Post subject: Re: Unusual brake wear |
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That shoe is not auto-centering on the circumference of the drum. It should be able to slip vertically up and down without much interference. Look for gouging, burrs in the shoe flange, crossbars and adjustment stars. Also look a the slope/slant in the groove base on the adjustment stars. The have to go the right way. _________________ John Henry
'57 Deluxe
'56 Single Cab |
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nlorntson Crazy VW Lady
Joined: March 13, 2004 Posts: 3776 Location: Twin Cities, MN
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Posted: Tue Jun 14, 2016 7:13 pm Post subject: Re: Unusual brake wear |
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You need to tighten up the cable where it goes into the backing plate and back off of the adjusting bolt.
Read up on the proper brake adjusting for cable brakes.
It's that single two click adjustment I love about the brakes on our 49.
But you do have to adjust up the cable occasionally and back off on the adjuster bolt. |
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Danwvw Samba Member
Joined: July 31, 2012 Posts: 8892 Location: Oregon Coast
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Posted: Tue Jun 14, 2016 8:28 pm Post subject: Re: Unusual brake wear |
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While adjustment's are important that's not going to fix it. It took me years of owning old Bugs before I figured this one out. Actually a VW Bug Mechanic in Iowa solved the issue. My 67 would always ware out the lead shoe first! Anyone else know why? It should be common brake shoe ware knowledge. Most that know it are gone now. Anyone know why? I will answer it shortly if not. _________________ 1960 Beetle And 1679cc DP W-100 & Dual Zeniths! |
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nlorntson Crazy VW Lady
Joined: March 13, 2004 Posts: 3776 Location: Twin Cities, MN
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Posted: Tue Jun 14, 2016 8:41 pm Post subject: Re: Unusual brake wear |
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They are servo-action, meaning that the rear shoe forces the front shoe harder up against the drum when rotating forwards. Hence the extra wear on the forward shoe.
Unequal lining wear between the leading and trailing ends of a shoe also be the result of weak return springs or an out-of-arc brake shoe. |
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Danwvw Samba Member
Joined: July 31, 2012 Posts: 8892 Location: Oregon Coast
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Posted: Tue Jun 14, 2016 8:48 pm Post subject: Re: Unusual brake wear |
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Sounds like good information but that is not what is wrong with his rear brakes! Something very specific and simple is causing it to ware the lead shoe like that. _________________ 1960 Beetle And 1679cc DP W-100 & Dual Zeniths! |
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usariemen Samba Member
Joined: August 28, 2004 Posts: 1745 Location: Germany
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Posted: Tue Jun 14, 2016 10:13 pm Post subject: Re: Unusual brake wear |
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Danwvw wrote: |
Sounds like good information but that is not what is wrong with his rear brakes! Something very specific and simple is causing it to ware the lead shoe like that. |
Just tell it or get lost.
Your little quiz show wont help. _________________ Master of my domain! |
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Danwvw Samba Member
Joined: July 31, 2012 Posts: 8892 Location: Oregon Coast
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Posted: Tue Jun 14, 2016 10:27 pm Post subject: Re: Unusual brake wear |
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I PM'ed the answer to the OP earlier so he knows what do do to fix it.
I was hoping others would know the answer but probably no one is looking at this post except us monkeys.
Actually "nlorntson" is explaining the technology of the shoe brakes but what is causing the un even shoe ware is simple.
The wheel bearing is worn out and or the axle tube that holds the wheel bearing does not hold it tightly. There may be too much play in the bearing. The bearing may move inside it's flange. _________________ 1960 Beetle And 1679cc DP W-100 & Dual Zeniths! |
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Mr. OGPaint Samba Member
Joined: September 24, 2010 Posts: 821 Location: Oregon
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Posted: Wed Jun 15, 2016 2:25 pm Post subject: Re: Unusual brake wear |
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Thanks for spitting that out Dan. Next time try being helpful from the beginning _________________ https://instagram.com/mr.ogpaint
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Patrick Hall |
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usariemen Samba Member
Joined: August 28, 2004 Posts: 1745 Location: Germany
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Posted: Wed Jun 15, 2016 10:02 pm Post subject: Re: Unusual brake wear |
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Danwvw wrote: |
There may be too much play in the bearing. |
There would have to be a lot play in the bearing to cause something like that. IŽd expect some running noise and probably oil leaking going along with that.
I am more with John. The shoe has to be able to move freely up and down to center itself in the drum. I would check if it does not stuck uncentered for some reason. _________________ Master of my domain! |
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johnshenry Samba Member
Joined: September 21, 2001 Posts: 9359 Location: Northwood, NH USA
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Posted: Thu Jun 16, 2016 11:42 am Post subject: Re: Unusual brake wear |
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I too highly doubt that it is a worn bearing. It were, you's see asymmetrical wear on the other shoe as well. _________________ John Henry
'57 Deluxe
'56 Single Cab |
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Brezelfahrer Samba Member
Joined: March 26, 2010 Posts: 65 Location: Vlaanderen
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Posted: Thu Jun 16, 2016 12:05 pm Post subject: Re: Unusual brake wear |
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Thanks for all the good advice, first of all.
Tomorrow I will put the new linings on, and start the assembly.
All parts are degreased, sanded and rusted parts are painted.
I never did any adjustments on these brakes, as I have driven it as it was when I bought it, and the braketest revealed an equal brakeperformance for the rear.
The linings on the brakes in the front where broken near the rivets, and I have changed them as they had a difference in brakeperformance of over 30%.
Probably the good cleaning, and a proper adjustment based on the documentary of Nancy (thanks again Nancy for that comprehensive piece of vademecum) like I did the front brakes before, will give much better results!
I will keep you updated on the brakerestoration! _________________ 1952 typ 1 european standard
1959 typ 1 european standard sunroof |
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nlorntson Crazy VW Lady
Joined: March 13, 2004 Posts: 3776 Location: Twin Cities, MN
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Posted: Thu Jun 16, 2016 12:59 pm Post subject: Re: Unusual brake wear |
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Brezelfahrer wrote: |
I never did any adjustments on these brakes, as I have driven it as it was when I bought it, and the braketest revealed an equal brakeperformance for the rear.
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Just curious how you tested just the rear braking performance? |
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Kjell Roar Samba Member
Joined: December 08, 2008 Posts: 1326 Location: Norway
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Posted: Thu Jun 16, 2016 2:02 pm Post subject: Re: Unusual brake wear |
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nlorntson wrote: |
Brezelfahrer wrote: |
I never did any adjustments on these brakes, as I have driven it as it was when I bought it, and the braketest revealed an equal brakeperformance for the rear.
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Just curious how you tested just the rear braking performance? |
I usually test it on gravel roads. _________________ I got a historic car, every scratch got a history...
My car, Aug. 4th, 1955 / an early 56: http://www.thesamba.com/vw/forum/album_page.php?pic_id=610438 |
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pastellgreen Samba Member
Joined: January 06, 2012 Posts: 1036 Location: Germany
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Posted: Fri Jun 17, 2016 5:47 am Post subject: Re: Unusual brake wear |
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nlorntson wrote: |
Brezelfahrer wrote: |
I never did any adjustments on these brakes, as I have driven it as it was when I bought it, and the braketest revealed an equal brakeperformance for the rear.
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Just curious how you tested just the rear braking performance? |
I think he means the brake test at the Technical Inspection Agency? They always test the effect on brakes on each axle. So they came to the state that the front brakes "... had a difference in brakeperformance of over 30%."
Last edited by pastellgreen on Mon Jun 20, 2016 2:09 pm; edited 1 time in total |
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Brezelfahrer Samba Member
Joined: March 26, 2010 Posts: 65 Location: Vlaanderen
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Posted: Fri Jun 17, 2016 11:06 am Post subject: Re: Unusual brake wear |
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Yes, it was at the technical inspection.
Altough the front brakes were faulty, I passed the Inspection.
"Yes Sir, I will take care of a proper adjustment of the front brakes!!"
Normally, one has to come back in two weeks at the latest.
But apparently this Inspector was in a good mood _________________ 1952 typ 1 european standard
1959 typ 1 european standard sunroof |
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tisius Samba Member
Joined: July 11, 2011 Posts: 1570 Location: Rotterdam,NL (+Chicago,IL)
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Posted: Sun Jun 19, 2016 9:43 am Post subject: Re: Unusual brake wear |
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Kjell Roar wrote: |
nlorntson wrote: |
Brezelfahrer wrote: |
I never did any adjustments on these brakes, as I have driven it as it was when I bought it, and the braketest revealed an equal brakeperformance for the rear.
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Just curious how you tested just the rear braking performance? |
I usually test it on gravel roads. |
....u turns ....use e-brake only _________________ drive it like you just robbed the bank
you don't have to be crazy to be into VW's, but it sure helps!!
.... if it ain't dutch, it ain't much! |
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nlorntson Crazy VW Lady
Joined: March 13, 2004 Posts: 3776 Location: Twin Cities, MN
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Posted: Sun Jun 19, 2016 8:23 pm Post subject: Re: Unusual brake wear |
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With cable brakes, both the foot pedal and the e-brake activate all four brakes all the time so I was wondering how you could tell if the braking of the front was different from the rear.
Side to side differences it pulls like mad, but front to rear? |
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pastellgreen Samba Member
Joined: January 06, 2012 Posts: 1036 Location: Germany
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Posted: Mon Jun 20, 2016 2:07 pm Post subject: Re: Unusual brake wear |
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In Germany f.e. we have two rolls in one line installed into the floor, each roll for each wheel of one axle. These rolls are driven by an engine and drive the two wheels of one axle, the one you want to test. You can not test both axles at the same time. During operation, the examinant presses the brake pedal and these rolls are trying to drive the wheels further. But as the brakes of the car are working more and more (till blockade), the wheels give the braking force back to the rolls in the floor that are able to measure this force that will be monitored at the same time on a very big monitor, showing the work of each brake seperatly. If the difference of the two brakes of one axle is too big, you car does not pass the technical inspection. They often beginn with the front axle, then testing the rear axle, then testing the handbrake (e-brake). Measuring the braking via pedal at a standard should not make a difference to a normal hydraulic brake regarding the kind of function, only the media is another one.
After you can compare the results of the front axle to the results of the rear axle, but I think that was not a matter of Brezelfahrer? |
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Brezelfahrer Samba Member
Joined: March 26, 2010 Posts: 65 Location: Vlaanderen
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Posted: Tue Jun 21, 2016 7:31 am Post subject: Re: Unusual brake wear |
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Yes Nico that's correct.
they examin front and rear axle separately till blockade in a floor installation.
front was unequal so I had to calibrate it, rear was equal thus no problem.
Altough they measure the force of the brake, it is not that what counts.
They can brake very weak till blockade, as long as the brake equally, there is no problem.
I once went the technical inspection in 2002 with my 1987 passat syncro permanent fourwheel drive, and had to change the lane of inspection to be able to check the brake performance on a special 4x4 brake They had never seen a non-SUV with permanent 4 by 4, except for some Audi's _________________ 1952 typ 1 european standard
1959 typ 1 european standard sunroof |
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