Simple Question Regarding Brake Job

Tidybuoy · 07-06-2007, 01:00 PM

I'm doing a brake job this weekend (yea! I just got slotted rotors all around, pbr metal master pads, stainless steel brake lines, super blue, and a power bleeder).

Anyway, the new rotors have a greasy film on them (I'm sure it's for rust preventative) and I'm wondering if that should be cleaned off before installing. I guess wiping with brake cleaner is all that is needed but I thought I would check in with the experts.

Also, I was planning on re-packing the front wheel bearings while I'm in there but I just realized that I forgot to order new bearing seals. It should be ok to keep using the old ones (only 22k miles on them) but I'm open for suggestions.

I've done brakes many times before but I always like to refresh my memory ahead of the job so any tips would be great. I've read up all the steps at Clarks Garage - damm, that is a great site.

Vern

Eldorado · 07-06-2007, 01:10 PM

dont worry about the film on the brakes. it prevents rust (ever see a set of rotors that have been in the rain after a couple weeks? they rust easily), as well as minor scratches or abrasions before selling. just put them on and the pads will do the work.

dont forget to brake easy for the first hundred or so miles until your rotors and pads have had a chance to adjust.

as for the seals, inspect them. if they're not hard, still flexible, and dont seem to be worn, then you're good to use them over again.

Icey1174 · 07-06-2007, 01:17 PM

You could spry them with brake cleaner to get the film off. The pads will take it off too. I guess it's perference.

Tidybuoy · 07-06-2007, 01:20 PM

Thanks! We've got perfect weather for auto maintnenance - 109 today but a cooling trend tomorrow (only 105). The grease might just drip off at this point.

Icey1174 · 07-06-2007, 01:22 PM

And it's 72 degrees here in Buffalo!

Tidybuoy · 07-06-2007, 01:41 PM

Quote:

Originally posted by Icey1174
And it's 72 degrees here in Buffalo!

That's terrible. We usually have to wait until January to get down to 72 degrees - lol.

Icey1174 · 07-06-2007, 01:42 PM

flash968 · 07-06-2007, 02:08 PM

remove the film - DO NOT put them on without doing that - if you do, you will never bed the pads down properly

most rotors that have that film on them require surfacing first - check with the source

Eldorado · 07-06-2007, 02:37 PM

i've never heard that before flash... where'd you hear it?

onZedge · 02:55 PM

The Bendix rep told me that all brake rotors must be cleaned before use. Even if you are just repacking the bearings, you will get grease on the rotors and that needs to get cleaned off. Your FLAPS carries brake cleaner for about $4 a spray can. Cheap. Also, it is never a good idea to reuse wheel seals considering the amount of work required to get to them in the first place. It's like doing a clutch job and not doing the rear main seal while you're in there, or a water pump without new timing belts. Your FLAPS carries them for about $5 each and will usually have them in stock as they are a fairly common size.

944gaz · 07-08-2007, 01:22 PM

Clean the film off or you could get judder.I always use celly thinners and have never had a problem.
Grease or oil contamination on the pads can cause them to grab and thus judder.
When drums were more common and a slave cylinder leaked or the bearing seal failed the brake would then grab.

Obin Robinson · 07-08-2007, 01:35 PM

when we did the wheel bearings on my 944, we took the brakes off and cleaned them thoroughly. upon reinstallation i noticed that the brakes worked better than before.

every time i've done brakes, or even removed them from the car, i've hosed them down with brake cleaner. i've never had a problem.

obin

gtroth · 07-08-2007, 07:16 PM

reference point - I just did front rotors (OEM/Zimmerman) and there was a card in the box that said clean with brake cleaner first to remove rust protection film.

924Sman · 07-09-2007, 06:28 AM

Yep use a cleaner!! Also the brakes need bedding and just taking it EZ is not the way to do it. There is a method in which pads are bedded.....Goes something like this.....run the car up to 30 mph then hit the brakes hard but no lock up, then drive and cool the brakes for a minute or so then increase the speed to 60 mph, then do the same. Do this up to 90-100mph. This may take 3 or 4 times. What you are doing is burning off the gasses created by the pad compound and tempering them in with the rotors(setting a groove).

Dal