Brake Pressure?

[Goland]

I recently bought an MX-3, and the guy I bought it from had done a lot of work on it. As a result, he knew what was going on with it, what sort of work would be coming up, and so on. He let me know that the lower ball joint on the front passenger side was nearing its end, and it was evident by the loud clunks emitted when going over a pothole or jacking the front up the car up.

So I went to NAPA, picked up the part, jacked up my car, took the wheel off, removed the ball joint and bolted the new one in. Took maybe 45 minutes. Since then, a few things have been happening that really freak me out.

First off, there's a little rubbing (the metal-on-metal kind) that happens once in a while, which is somewhere in the rotation of the tire. Sometimes it's loud, sometimes it's not there. Sometimes it's a click, sometimes it's a scrape. But it's something along the revolution of the wheel.

Secondly, and more importantly, the brakes have really gone bad. I think it might be related, but I'm not sure. My brake/clutch fluid is in the good range, right under the "Max" line, but the other day I was out at the beach, driving around, when I apply the brakes to find my foot travelling way farther than I was used to before the brakes were applied. It was so noticeable I stopped the car in the middle of the road... Took a pause... And started going again once I realized the brakes had in fact worked.

Today I was going down the street when the light up ahead turned yellow. I pushed on my brakes... Nothing... I slammed on them... Loud screech from only my front right tire, and I didn't really slow down enough. Ran a red light as a result, was pretty shaken.

Anyway, the brakes work, you just have to coax them into it by applying, releasing, and applying the brakes over and over (sorta like pumping them up). This leads me to think there's some sort of loss in pressure of the brake fluid, but I'm not seeing any leaks.

Keep in mind that I'm not an EXPERT at working on my car or anything (obviously; I'd have fixed it myself already) but am trying to learn. I'm 19, this is my second car. I'm a lucky guy, I know!

Anyway, any help would be appreciated. I don't want to have to take it to a shop. I really want to be able to do my work myself, but I can't just hope this problem goes away.

EDIT: This MX-3 is lowered, with Eibach springs from corksport (decals in the back window attest to this), I've been reading up on a few other things here about the clicking/rubbing/scraping noise, but nada about the brake issue.

[blackops032]

replace any worn lines and flush the system. but before you do try and locate any leaks. check to see if your fluid level dropped too.

[Goland]

I took the wheel off to inspect what was going on down there, and it turns out that the brake rotor is scraping against the inside of the caliper. It's a few millimeters too far in (towards the engine). What could cause this? Brake fluid appears to be fine, as there have been absolutely no leaks, decreases in brake fluid level, or any "wet" looking surfaces around the brake line. In fact, after putting the wheel back on, the brakes have been working just fine... I don't know what I did to do that. However, the scraping is still there once in a while.

Is there a way to shim out the brake rotor or something like that so that the scraping ceases?

[PurpleDinosaur]

I'm not sure how just taking the wheel off to replace a ball joint could cause it but your break issues sound a lot like air in the brake line on that wheel... Air is way more compressible than brake fluid so if you get even a small air buble in you lines you will get a spongy feeling brake pedal... that you got the other side to lock up in a panic brake suggests that you may only have air in the side that you took the wheel off...

I'm probably on the right tack but not 100% correct... another will chime in to set me straight no doubt.

-Barney

[Goland]

That really could be it... I loosened the brake hose and some fluid poured out (the brakes were engaged) and I tightened it back up. It could be that I bled the brakes without really realizing it, as the brakes have been completely fine ever since.

The problem with my rotor still irks me. I inspected the passenger side wheel today and it's very clear that there is a difference in clearance between the rotor and the part that protrudes inside the brake caliper. The noise has subsided for a few days though, so it could have been the brakes were also causing that problem (I haven't inspected the clearance again since driving it).

[Goland]

The car's jacked up outside, some really loud, annoying noises have started coming from the same stupid wheel, so I decided to have a look.

I've got a good half inch to an inch of easy play on the wheel, and the brake rotor is moving around with it. The brakes are completely disengaged, so I probably wasn't noticing this before because I always have the front brakes locked in position when it's parked. Not this time, though.

I know that's the sort of thing that happens to a bad ball joint, but what gives? Nothing's even close to being loose on the ball joint end of things, but I don't know what else would be letting the wheel move around as freely as it is right now.

This wheel is giving me so much trouble! Argh!!

EDIT: Alrighty, I took the wheel, caliper, and rotor off. The hub of the wheel jiggles, and the axle moves right along with it. Nothing else moves, just those pieces. This should rule out the ball joint and strut, leaving me with... What.

I don't know what all the connections and hinges are called in the wheel well, but when I jiggle the wheel hub (the part with the lug bolts sticking out) the only thing I can see moving as a reult is what I assume is the axle (a shaft that turns with the wheel and juts out into the engine bay).

It's not jiggling inside the engine bay, but the focal point of the movement is the angled connection between the downward-sloped axle and the parallel-to-the-ground wheel hub.

Is this something I can change myself or am I going to have to throw in the towel and let someone else handle my car?

[PATDIESEL]

Let someone else handle this one as it is cause for concern. Sounds like you have an awefully bad wheel bearing. This is letting the wheel and thus the rotor, which is held on by the wheel, move around. This movement is wearing out the brake pads or not letting them engage properly. To change the wheel bearing you need a hydrolic press, about 100-150 from Harbour Freight. However, changing them requires a bit of knowledge and some attention to detail, as well as some special tools. You also need to have the spindle and hub checked. They are not usualy replaced when replacing the bearing, but if the bearing gets bad enough it can damamge the seating surface of the spindle or hub, which will in turn wear out a new bearing Very quickly. If you get an expensive quote to repair take it to a second shop for a second opinion.
On a note: the wheel bearing is actually what holds the wheel onto the car. If the bearing wears out too badly the wheel can come flying off the car when you are moving and most likely turning. So, you need to get this checked out and repaired soon. If you can find someone to help you that has replaced a wheel bearing before go for it. Just not a job for someone who just started back yard mechanicing.

[Goland]

The bearing was it, got it replaced and it drives like a whole new car. Brakes are more responsive than they've ever been since I owned it, the noise is all gone, and it wasn't as expensive as I thought it would be (~$210 for those interested).

[PATDIESEL]

Good deal, glad we could help you get her running straight. Bearings can be a PITA to fix so that price seems pretty good to me. I've never paid to have one replaced, but it takes me a couple hours to complete a bearing replacement.