Smoking Brakes?

Hi Guys,

While driving into town today, and in the rain, I noticed small plumes of smoke rising from under my right front wheel arch at rest.

I just want to canvas some opinions here... My first feeling was that it was simply steam resulting from water hitting the discs or something hot inside the wheel, but then I thought, no, I couldn't be that lucky...

A sticking caliper?

Leaking fluid?

My brake pedal is a tiny bit spongy at maximum foot pressure, so could that be a clue?

HELP!


Matt Holcomb




[This message has been edited by Matt Holcomb (edited 11-01-2000).]

I can think of two things. Your caliper could be stuck causing your pads to drag and heat up the disk, hub and wheel. Another thing could be a front oil cooler depending on the year.

did the smoke look like steam? If you notice it again get out and follow your nose. My car smelled like burned brakes when the caliper froze up. See if you can find that smell of a semi-truck after it has come out of the mountains. If so then its the brakes. YOu could also lift the front of the car and see if you can spin the wheel. There should be no drag of the pads without the foot on the brake. Make sure the car is supported properly. Hope this helps.

Jamie
71 911T targa

Hahahahaha. I had this same concern, until I realized that this is where my oil cooler is. Upon peeking, it was clear that the tire was throwing rainwater onto the (pretty warm) trombone cooler, making steam.

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'83 SC

Looks like I'll be taking that right front caliper back to the store. I was just about to install it this weekend!

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Brian
'81 SC Targa

I hope my HAHAHA was not viewed as rude. Apologies if it was.

While I recognize that brakes can bind and cause great heat, I am still of the belief that steam (smoky looking stuff) rising out of the right front wheel well is steal coming off the trombone cooler.

but on the off chance that a caliper is binding....while I'd agree there should be little drag when you sin the wheels with the car in the air, there will be some drag anyway. you will feel and hear the brakes as you do this. And the drag is too much if it is at all difficult to turn the tire and wheel. But the drag will be there.

I suggest another test. stop using your brakes a few miles before you get home, if this is feasible. As you coast into your garage, use the handbrake. Immediately get otu of the car and CAREFULLY touch or put yopur hand near the right front brake parts. Careful, because if there is much friction going on there, it could be HOT. If it's not hot, this is not your problem. I'd hate to see someone deal with a caliper problem unnecessarily. Of course, maintaingin and rebuilding calipers is a good idea, but it is a pain the the ass, and can be quite expensive if you have someone else do it.

Brakes are probably the most simple and reliable system on the car. So reliable that motorists are quite surprized if they ever experience brake failure. It almost just never happens. Again, I recognize that a caliper may be binding, but in my humble opinion, it is VERY unlikely that a caliper could bind to the extent that there is enough heat to make SMOKE. And if this happens just hold your hand close to that brake rotor and you will know.

I think steam was comning off the trombone cooler.

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'83 SC

I had a brake hose on a corvette that failed and somehow started valving. It would let fluid go into the caliper but not let the pressure release. As the caliper (and fluid) became hotter the wheel would eventually lock up. I had to bleed the pressure off at the caliper to release the brake. Seems like if it were a caliper problem the car might pull slightly. The oil cooler came to mind when I read your original post.

Superman,

I started laughing myself when you began your reply with laughter – for how could I have forgotten the oil cooler?!

It all made sense, although I'm probably not out of the woods just yet with regards to the right, front brake caliper: when I was adjusting tire pressures during my last sprint event, I could smell that very pungent, hot carbon smell when checking the tire pressure of the right, front tire…

Anyway, I'm going to have it looked at next Tuesday. Hey, at least we’ve narrowed it down to two possible causes!

Thanks Superman, and thanks guys for your feedback.


Matt Holcomb

I was really happy when I read your comments about the oil cooler causing the problem. I had thought about the oil cooler, but figured the steam would come up on both sides and the front. This saved me a lot of trouble!!!