w140 Rotors & Brakes - PeachParts Mercedes-Benz Forum

#1 03-04-2003, 02:37 PM

Hi,

Does anyone know how often you need to turn the rotors. I just did all the brakes and sensors on my '97 S420 and inspected the rotors ( I did not measure them for thickness) and they looked good. I slight ridge on the outside edge.

Also trying to find the Ezibleed system. Where can I find it ?

Thanks for all the help.

Tom

Kestas · #2 03-04-2003, 02:57 PM

Rotors should be turned only if there is pulsation in the brake pedal from warpage, if there is deep scoring, or in some cases if there is bad corrosion on the rotor surface... or perhaps a bad ridge when you want to put new pads on. How deep the scoring and how bad the ridge is a judgemental call.

Some people insist on turning rotors ANY time new pads are installed. I'm somewhat more conservative on turning rotors, since you lose "meat" from the rotors each time you have them turned making them that much closer to discard thickness. This "meat" is needed for heat transfer and stopping power. Plus, some machine shops hog off more material than needed when cleaning up your rotor. They don't want to "baby" the process.

#3 03-04-2003, 04:33 PM

Kestas,

Thanks for the response. I had heard that same thing about turning the rotors on every brake job. What are your thoughts about the new drilled and cut rotors for heat transfer?

Thanks again,

Tom

Kestas · #4 03-04-2003, 05:12 PM

They look cool and trick, but don't use them unless you have to (or you want the cool and trick look). They're for demanding heat transfer applications such as racing. Downside is the pads wear out quickly and sometimes the drilled rotors can develop thermal fatigue cracks at these holes, especially on home-made jobs.

#5 03-05-2003, 12:20 AM

Thanks for the info. No raceing in my wife's car. Do you know where I can get the Ezibleed system for bleeding/changing the brake fluid?

#6 03-05-2003, 12:33 AM

Thanks guys.
I found the Eezibleed system. I was spelling it wrong

.

I hope there are no challenges with flushing the ABS system with it.

myarmar · #7 03-12-2003, 10:53 AM

I have this simple digital caliper add-on kit to measure rotor thickness and drum diameter for sale on Ebay.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=35625&item=2406565768

Quote:

Originally posted by HPF
Does anyone know how often you need to turn the rotors. I just did all the brakes and sensors on my '97 S420 and inspected the rotors ( I did not measure them for thickness) and they looked good. I slight ridge on the outside edge.

Tom