what should I use to get cosmoline off of rotors?

What do you mean by cosmoline? The primer like paint on the rotor surface? If so then I would do anything about it. I bought MB rotors from dealer with the primer like paint on the rotors and the paint wore off the rotors very quickly after some braking. The car was a 95 W124.

Any foreign Material on the rotors is not a good idea. The coating will come off with spray brake cleaner or contact cleaner.

Tim

the grey primer on the rotor is not something that needs to be removed before use.

Cosmoline (wax) used in shipping protection should be removed by dealer before delivery. If any is on rotors it will burn off after the first couple of brake applications

I second Ethan's comment. The MB Parts Department personnel advised that there is no need to remove the gray primer that is on new rotors.

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Fred Hoelzle

I just heard there was a coating on new rotors, I can't tell by just looking at them if there is. so I should just drive and let the pads wear it off if there is any? they are atx pads and rotors.

All the rotors I've ever gotten were coated in cosmoline (grease, for those who aren't familiar with it).

If they are primered (dry coating, not slimy), it will wear off immediately. Cosmoline (greasy stuff) will, too, but only after you've crashed the car from greased brakes.

I always rough the rotors with some coarse sandpaper, too -- this keeps the pads from "groaning" as you come to a stop.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Use brake cleaner or brake parts cleaner.

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82 Rabbit diesel (first d), 84 Jetta turbo d (300k when sold), 83 240d (305k when sold), 84 F250 6.9d w/Banks turbo(parts truck), 86 F250 6 cyl.gasser(waiting for 6.9d), 84 300d ( 347k Sold 8/04), Y2k New Bettle TDI (185k miles), 95 740IL (wifes), 87 300TD (206k Sold 7/05), 05 Passat TDI Wagon

I also use clean paper towels. I keep wiping the braking surfaces with a towel sprayed with BrakeKleen until nothing comes off on the towel.

There is nothing worse than doing the whole brake job and then getting a pulsing rotor from missing a sport.

Also break-in the new rotors slowly. Take it easy for the first few 100 miles or so to let the pads match the surfaces and establish a heat set. Rotors done this way seem to last a long while.

Be sure to double-check the wheel bolt torque- once will assembly and once again after just a few miles.

Haasman

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'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)

thanks everyone, I bought some brake cleaner and will spray away!