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Sat Jul 02, 2016 11:38 pm

So I just recently started to upgrade the rear brakes on my vw from drum to disk. It seems to be going ok, but I would like a second set of eyes to tell me if it looks good. I pulled the old drums off and placed the caliper holding plate on. I then put the paper spacer on between the old bearing and the new adapter. This seemed to be fairly greased up, so I didn't replace the bearing housing and rubber gaskets. The caliper break pads in the end rubs slightly against the rotor, should I be concerned about this? Is there an adjustment I can make, as there isn't much space between the pads and the rotor. Please let me know if you have any advise

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[img]https://www.thesamba.com/vw/gallery/pix/[/img]

Sun Jul 03, 2016 5:05 am

The pads look to be evenly spaced against the rotor, so it looks like you have it centered. Pads should not be riding against the rotor though. they might be a tad thick. The way disc brakes work, if you never took a caliper apart, is, the piston sits in the bore, and it is sealed by a square cut seal.

the square face on the seal allows for more sealing area, but it also allows for more friction to resist the piston sliding past the seal. So, as the brakes are applied, the seal actually bends a little in the middle (flex).

as you release the brakes, it retains it's shape and the piston withdraws away from the rotor.

As the brakes wear, the piston will slip in the seal and not retract as far the next time. this way they are always in adjustment.

This is why you should never 'top off' a master cylinder after the system is properly bled. The level of the master cylinder is a great indicator of how much brake wear you have.

Sun Jul 03, 2016 10:00 am

Axitech, thanks for the reply and for the information on the calipers. I am new to all things automotive and am doing some self learning, so all information is always appreciated. If the pads are slightly too thick, would they rub down to a good thickness? Or is this a bad idea? The one on the left has a fairly good amount of room, but the outer most pad slightly rubs in one area, due to a small amount of "warpage" on the rotor it will touch it barely. My next trick will be to try and figure out how to bleed these with the cutting breaks.

Sun Jul 03, 2016 12:07 pm

Axitech wrote: The pads look to be evenly spaced against the rotor, so it looks like you have it centered. Pads should not be riding against the rotor though. they might be a tad thick. The way disc brakes work, if you never took a caliper apart, is, the piston sits in the bore, and it is sealed by a square cut seal.

HUH.... That IS the way they work...

Dale

Sun Jul 03, 2016 1:14 pm

So they should be rubbing slightly?

Sun Jul 03, 2016 8:16 pm

Yep should be slightly rubbing. Wheel should still spin easily though.

Tue Jul 05, 2016 5:27 am

Is the bracket supposed to be vertical? What brand, looks like nice calipers.

Clean and inspect the seals and they look good. As long as the wheels will spin when the pedal is not pressed, they are released.

Best regards, Jeff

Mon Aug 01, 2016 5:20 am

I've find many article related to swap drums for discs on the rear of a beetle but i've been trying to do this with the front wheels, where I live in Mexico is kinda hard and expensive to find a full set of front brasilia front brakes or a kit of disc conversion brakes from jbugs or pages like that, so i've been thinking if may be possible to adapt discs from another car onto the front of my Standard?