1957 Series 62-My Brakes Locked Up! Resolved Itself-But WTF???

[CORVAIRWILD]

So I decided to take my recently delivered 1957 series 62 Cadillac on a shake down run through the Catskill mountains, and I stopped at a scenic overlook to take some pictures, and as always I engaged the emergency brake. When I went to move the car, the brakes seemed to be locked up. I crawled underneath and worked the E brake cables and they seemed to be working free as I could hear the mechanism working inside the brake drums. So I after a 1/2 an hour of tinkering with a variety of things, and repeatedly attempting to move the car, I heard a bit of a groan from the brake pedal under the dash, and brakes disengaged, and off I went.

So what happed? My gfriend noticed a bit of a dull clicking noise after I would release the brake pedal as we drove the hour or so home, and the issue never reccured.  I did notice the brake pedal seemed very "hard", like it was "stuck" under the dash, or where it pivots on a belcrank(?) thru the firewall during this episode..

I haven't crawled under the dash as of yet... thots?

For the record, I'm a mechanic and I fix just about anything mechanical

[walt chomosh #23510]

Golt,
  Beautiful car!....not sure about your issue without more info but I can GUARANTEE that any hydraulic brake system that doesn't have enough free play in the pedal will lock up. The brakes will release after cooling. Then there's the flexible hose that deteriorates internally and will pass fluid to the wheel cylinder but not allow it to return, of if it does it will return slowly.(I've experienced these problems more then once)....walt....tulsa,ok

[CORVAIRWILD]

This wasn't an issue at all with hot brakes, as I had just crested the mountain and was on my way down when I stopped at the scenic overlook, and the car was actually sitting for about 30 minutes when the issue arose, so I'm really perplexed, and I'm also a very experienced car mechanic, and I've driven my share of junker clunkers, and I can pretty much fix anything the on the side of the road given some tools and a flashlight , and at my age, my reading glasses lol

[Dave Shepherd]

The key is whether all the brakes locked or just one.  You could use a non contact thermometer  to check wheel temps after  some brake use and see if one is hot. A bad booster could cause all the wheels to lock, but this is rare.  Rereading your post, it does sound like a booster issue or the pedal not fully retracting.

[CORVAIRWILD]

Dave, the car wasn't moving when this happened,  so I'm sure it was a mechanical issue under the dash-cowl area. I drove another couple of hours after that, and there was no issue whatsoever, it just returned back to the way it was

[Dave Shepherd]

Ok I had this issue with a 57 Cad in my shop and the booster was the root cause, of course any binding in the pedal linkage can cause this .  The Hydro Vac brake system  has been problematic in those year cars. I f this  happens again crack the line out of the booster see if the brakes unlock.

[CORVAIRWILD]

Dave... crack the hydraulic line or the vacuum hose?

[Dave Shepherd]

The hydraulic line that feeds the cars brake system, should be little or no pressure during the event when the brakes are locked.

[CORVAIRWILD]

Yes, exactly, but I felt great pressure as I was taking my gfriend for a joyride, and time was a tickin... I did have a complete tool kit with me, but I ended up just banging on the steering wheel and cursing lmao

[gkhashem]

I see your a mechanic. Brakes not letting go, then did you remove the wheels and inspect the drums and shoes?

I will ask again did you go through the brakes? I do not see anywhere were you did unless I missed it. I see tinkering, etc.... Did you change hoses, wheel cylinders, bleed brake lines or just hop in and go on a newly purchased 65 year old car?

So until you take a closer look not sure what one could solve here on a message board.

Walt had a good idea

Golt,
  Beautiful car!....not sure about your issue without more info but I can GUARANTEE that any hydraulic brake system that doesn't have enough free play in the pedal will lock up. The brakes will release after cooling. Then there's the flexible hose that deteriorates internally and will pass fluid to the wheel cylinder but not allow it to return, of if it does it will return slowly.(I've experienced these problems more then once)....walt....tulsa,ok




Even hoses that look new on the outside can collapse.