I smelled something burning the last mile or so on my way home from work today, and when I pulled into my driveway I saw smoke coming out from around both rear wheels. The driver side was worse, lots of smoke, and just a little on the other side, but smoking nonetheless.

They're stock power drums all around. I'm letting them cool down before I pull them and have a look. It's been less than a year and a thousand miles since I did a complete brake job, cylinders, shoes, and hardware and they've been working fine. My emergency brake is connected, but I don't use it. I'm assuming they just never released completely after being applied somewhere along the road. Any ideas on what can cause this?

Does it smell like burning brake parts? (pads, etc.) Or does it smell like a burning oil maybe? Maybe some type of grease is stuck in there, but since it is both rear wheels, it leads me to believe it has something to do with the e-brake. Maybe get under the car and loosen the ebrake cable adjuster, and try and make sure it is retracting, and not stuck opn at all. Another thing is maybe the self adjusting dealies on the rear brakes has over tightened them. Wehn you go in reverse, then hit the brakes real hard, they tighten, might try pulling both rear wheels and their drums to see if everything is clearancing o.k. As long as they are working ok, there shoudlnt be too much harm with the smoking, but it still isnt good. hopefully this may help... graemlins/beers.gif

I had a similar problem, turned out the master cylinder was bad, after the car sat a year or so,I took it out for a drive and it kept felling like the brakes were slightly applied, When I stopped to look at it there was smoke pouring off both front rims,also smelled it.

What had happen was the master cyl. was acting like a check valve, it let pressure apply to the wheel cylinders but didn't let the pressure return to the master once I released the brake pedal.must of been just the part the controlled the front brakes.
Had to crack the bleeder loose to relieve pressure, tighten back up and limp it home.

Not saying it's your problem, but you may want to check it out.

Was your car dragging like th ebrakes were on or did you just smell it?

I had a similar problem, turned out the master cylinder was bad, after the car sat a year or so,I took it out for a drive and it kept felling like the brakes were slightly applied, When I stopped to look at it there was smoke pouring off both front rims,also smelled it.

What had happened was the master cyl. was acting like a check valve, it let pressure apply to the wheel cylinders but didn't let the pressure return to the master once I released the brake pedal.must of been just the part the controlled the front brakes.
Had to crack the bleeder loose to relieve pressure, tighten back up and limp it home.

Not saying it's your problem, but you may want to check it out.

Was your car dragging like the brakes were on or did you just smell it?

After giving it some thought, I'm sure the brakes were dragging. Not enough to stop me, but it did feel like I had downshifted whenever I took my foot off the gas (it's an automatic). I only have about 100 miles on the new engine - still breaking it in so I really didn't notice the brakes until they started to stink.

I guess I could try a new master cylinder, but this one's only a year old. I'll eventually be upgrading to front discs - when I do will I need a M/C different than the one used for drums? If so, maybe I'll do the upgrade earlier than planned.

Something to check out first. I had a problem on an 87 Suburban that I'd never seen before. The brake shoes wore through the 3 pads on the backing plate.When you hit the brakes it would catch in the groove and drag the brakes. It actually turned a pair of drums blue! I had the whole rear end apart before I found it. I welded up the pads and ground them back down and no problems.

Jeff

I hade the same problem on my 68 chevelle. Turned out to be the rear flex hose it was acting like a check valve.The rear brakes always had drag on them. Got a new hose and no more problems. You can do a search and find my old post about this problem. Dom

Yes, I forgot to mention a collasped flex hose will act like a check valve too, Good call Blue !!!

I also have an automatic and it was down shifting because the brakes were applied enough to drag the car down. I too have 4 wheel drums and will be changing to front disc's shortly.

I the master cylinder cost me 13 bucks at advanced auto and would need replaced if you do the front disc conversion. BUT for 13 dollars and (if that's your problem) you could be driving it until you put the disc's on.

Just because the master was replaced 100 miles ago doesn't mean it isn't bad from the factory or re-build plant, also could of had bad(old fliud) still in the lines.

Do yourself a favor and check the flex hose for being collapsed and replace the 13 dollar master cylinder if flex hose is ok.

Let us know what you find.

Thanks for the info. I pulled the drums and looked at the brakes yesterday, and everything looked fine - except my drums were kinda blue. I ordered a new hose and picked it up today - don't think it's the right one though, it's got a brass distribution block as part of the hose. Anybody got a Bendix part number for one that screws into this block?

I couldn't get the old hose off of the hard line and wound up stripping the nut on the fitting. I cut the hose to unscrew the other end from the brass block, and although the hose looked OK on the outside, the inside was pretty nasty. I'm hoping this was the problem.

Back to the stripped fitting - I decided I'll just order a new hard line. Looking at it from under the car, it runs along the inside of the frame and doesn't look like it'll be too difficult to swap. Any suggestions here?

Another question on a disk brake swap - would this hard line stay the same? I'd like to assume that a new proportioning valve would be installed where my current one is down on the frame in the back of the engine bay.

I have not done my swap yet but have asked many questions about it. The thing you see monted "on the frame" is NOT the proportion valve,(don't worry I thought that too). It is a distribution block. I was told this could stay and I was told it had to come out ??? The proportion valve goes up near the master cylinder. I bought a whole used set up and it was mounted on the hard lines coming off the master.

Do yourself a favor and do a search here and see how many questions come up on this. You can pick up some good info there.

68Elkie,

The rear hard line will need to be shortened if you install discs. If you are interested, I have a rear brake 11" disc setup that I used fot 10 miles when I was trying to decide what I wanted to do. It is the MP Brakes kit with brackets, cadillac calipers (with handbrake mechanism and cable) and rotors. Make me an offer.

Theo.
'68 Chevelle conv.

Thanks Theo, but I'm looking at a Front Disk swap and would need to do that before even considering swapping the rears. So, what did you decide to do?

I decided to experiment and try the 13" front & 12" rear Corvette brakes. It became a real ordeal as the information on the web is not complete... It took me several months to get the system working. I now have it working with the hydroboost system. I like it but it is costly and I am not sure how much better it is... You need 17" wheels for this setup.

I also have an unopened/unused set of front disc brake kit from ECI. I think it is the best 11" setup. You can see it at:

ECI Disc Brake System (http://www.ecihotrodbrakes.com/disc-brake-kit-with-drum-brake-spindles_ec-723ack.html)

I will sell it if I get a good offer or I'll list it in eBay together with the rear setup (from MP Brakes).

Theo.