kauai1800

Aloha Guys,

Not sure exactly what's up but I felt a slight vibration and noticed that the driver's side rear wheel was very hot and smelled hot as well. I suppose it could be a brake caliper that's frozen and rubbing - can you folks think of anything else it could be? Maybe I didn't completely release the e-brake? I read we have a tiny drum brake on the rears that is how the e-brake works. Is it on both sides or just the driver's side?

Just tossing this out to see if you have any ideas. Thanks!

zakmartin

Jack up the rear of the car and have a look. Then report back.

CK_32

iTrader: (1)

How’s the wear?

Have you lifted the car and checked for play?

icer5160

iTrader: (4)

Yes, the E-brake on the Z uses a smaller internal drum brake design. If you left it engaged, I would expect both wheels/rotors in the rear to get incredibly hot and potentially warp or crack. Since you only mentioned one side showing signs of excessive heat, I suspect you could have a sticking brake caliper or e-brake shoes.

You live in Kauai and I know first hand how much rainfall you guys get there making rust a very common/big problem for vehicles. Nearly every beach truck I saw was suffering from severe body/frame rust. Not surprisingly the oldest ones I saw in service were all Toyotas!

Long story short, if your brake caliper piston started rusting (creating pitting) where it rides against the inner seal, it can easily start to stick and even leak brake fluid.

My suggestion...pull the wheel off and remove both the caliper and rotor. Look for excessive rust and any signs of leaking brake fluid around the piston. Check the reservoir fluid level. Make sure your brake pad return springs are functioning and that both pads have freedom to move (not binding) in the caliper bracket. Also check the rotor for discoloration, grooving, and signs of uneven wear.

Some other thoughts... Does the vibration you describe only occur "during" application of the brake pedal or does it happen all the time?

-Icer

kauai1800

Thanks for the good comments everyone. Yes Icer rust rules here on Kauai and it really sucks for those of us who like to work on cars. Changing something like an exhaust system is basically a joke because every fastener will be just a piece of solid rust.

I drove it around for a short period and it was fine but on the 25 minute ride home this same wheel got very hot. My infrared thermometer read 410 on the rotor of the “bad” wheel while the others were 180. So yeah it’s looking like a lightly stuck caliper or something similar. It’s not really bad because the car rolls pretty freely but I can hear a faint grinding/squeal at under 5 mph after it’s hot.
It’s a bit of a bummer because I spent last weekend replacing 2 ignition coil packs so I want to drive around rather than spend another weekend de-bugging this problem. But it’ll warp the rotor if I don’t fix it - if it’s not already warped. Classic 14 yo car problems...

icer5160

iTrader: (4)

Yes, better to get it handled ASAP. Once you confirm the issue you can weigh your options. But my money is on a sticky piston. You can rebuild the caliper cheap, but you can also find non-brembo calipers used for super cheap to.
-Icer

iideadeyeii

iTrader: (6)

Caliper. Might of fried the wheel bearing too from the heat

zakmartin

Based on what you gathered from the thermometer read, this certainly does sounds like a stuck caliper. You can try retracting the piston and see how much trouble it gives you. If you need to re-hone the cylinder, then soak everything on the caliper in penetrating oil the night before, get a rebuild kit and go to town. It's way cheaper than buying a new caliper (and unless you're buying OEM, it's most likely just a rebuilt caliper anyway.)

As iideadeyeii mentioned, be sure to check the wheel bearing for damage. That's a bit more of a hassle to fix since you'll need access to press if you want to do it yourself.

Like you said, it's a 14-year old car.

Still, you gotta love the Z.

icer5160

iTrader: (4)

Btw, Mr. Kauai, hows the restoration of the Z coming? As I recall, you purchased the 06 Roadster from an Older lady that had some mold or algae issues. Last I remember you had the radio fixed and removed a bunch of algae growth?
-Icer

kauai1800

JMII

I felt that way about brakes too... but then had a few friends teach me the basics. Now a caliper and rotor swap is an easy job. Since I track my Z I was pretty much forced to learn how to deal with brakes because you go thru pads like crazy. Just two weeks ago I did the brakes on my brother's Porsche Boxster GTS. Pad and fluid change (plus removable of the stock wear sensors) took us about 2 hours mainly because you have to remove the caliper on the fronts to swap pads.