Pads scraping on rotors - Honda Prelude Forum

ar5enal · 09-03-2002, 10:54 AM

I did the Legend caliper swap over the weekend with Powerslot VTEC rotors. I followed the install exactly as indicated in the NTPOG write up for pad and rotor installation. I used an old pair of VTEC pads (the backing material) as shims for the outer pads. My problem is that the pads are scraping against the rotors even when the brakes are not depressed.

I had to drive home like this (about an hour) and towards the end of my trip, the vibrations got a bit worse. They go away whenever I brake (understandable), but come back otherwise. It seems like it gets worse when I turn left as opposed to right.

I hope I haven't warped my rotors, because they were really hot when I got home. There's also a ton of brake dust on my front wheels. Does anyone know what this is, or have any advice? Any help would be greatly appreciated.

U.K VTEC · 09-03-2002, 12:47 PM

Maybe the old pads you used as shims are still slightly too thick and are causing the 'real' pads to touch the rotor. Or, the pistons in the caliper hadn't returned fully when they were removed and are sitting a bit proud, pushing the pad out a bit. It's hard to tell without seeing the car so I'd look at both.

If the shims are the cause, have them skimmed a little to give a bit more clearance.

ar5enal · 09-03-2002, 12:59 PM

I'm pretty certain that the pistons were fully compressed at the time of install.

My guess is also that the shims are too thick. When doing the install, we even went so far as to omit the factory shims in order to get proper clearance. I'll look at it tonight, but I suspect that you're right.

Mainly, I'm worried that I may have irreversibly damaged something.

U.K VTEC · 09-03-2002, 01:03 PM

Worst case scenario is that the rotors may be warped and the pads have worn more than they should have.
Only way is to see whether the steering wheel shakes when braking (caused by warped rotors) after you have remedied the initial problem.

Good luck!

ar5enal · 09-04-2002, 11:30 AM

Okay, so yesterday I get home with an hour of daylight left. That's enough time to set the front of the car on jackstands, and remove the wheels, calipers and rotors.

Just eyeballing it, my rotors appear to be okay, and there is no uneven wearing on my pads.

Scary thing is, my lugnuts were a lot looser than when I originally torqued them down. A couple of them were even loose enough so I could remove them by hand. I haven't had a chance to put the rotors and wheels back on to check for play in the hub bearing, but could this be my problem?? I'm guessing that shot wheel bearings would result in the same sort of symptoms. I don't really think that scraping pads could cause my wheel to shake so badly that it untorques the lugnuts....or could it?

brendon2k · 09-04-2002, 08:57 PM

I think the lose lug nut colt be part of the problem. The lugs/rims tightned down help hold the rotor in the correct positon. I don't think your lugs should loosen up though. Are you sure you torqued them to 80ftlbs? My thing is if the shim was too big you shouldn't have been able to get the pads over the rotor.

ar5enal · 09-05-2002, 11:10 AM

Here's the latest:

My wheel bearings are okay. I put on the rotors and wheels yesterday, and there's no play in the hub.

I went over the area where the rotors sit with a wire brush and dremel to get any rust off. Making certain that there was a good seat, I put the rotors back on.

As soon as I can, I'm going to get some thinner aluminum to make new shims. (The old brake pad backings I had were ~7mm thick and the shim only needs to be 5mm max.) I just need to find a sheet metal place that has some scraps of 3-4mm thick aluminum lying around. Then, find someone with a bandsaw to cut the bastards.

I can't think of anything else I've done wrong. I'm pretty sure that I torqued the lugs down properly, but I'll make absolutely certain I do this the second time around. Hopefully I can get all of it done this weekend.

brendon2k: Yeah, I agree that the loosened lugs definitely exacerbated the problem, as it got noticeably worse when I pulled off the freeway to go home. I'm also a bit puzzled by how scraping pads could loosen lugnuts, and don't have a ready explanation. I only hope that fixing this shim thing, and redoing the install will make my problem go away...