52 3100 brakes locked

Hello all, took old boy for a ride today and brakes froze. Pedal is in up position and will not move. Not sure which wheels are braking. Emergency lever works well. Waiting for tow truck to deliver truck.

My thought is to put it on jack stands and see which wheels are locked or dragging as a first step.

Open to ideas and suggestions.

Denis

 

I would first loosen the brake lines at the master cylinder. If this frees the brakes then check to see how much free play you have in the actuator rod. If one brake is the only one locked up loosen the bleeder valve and see if that frees it. If it does the rubber hose has gone bad and become a one way valve---replace them all. About the only non fluid thing that can happen is for a piston to stick in a wheel cylinder bore.

 

Thanks I will add that to the troubleshooting.

 

Got it on jack stands. Front wheels have a bit of drag, rear wheels are freerer. Brake pedal only depresses about an inch. Background, brake system totally redone about 18 months ago or so. Very few miles since then.

How much movement should there be in brake pedal/piston?

 

Shorten the rod from the pedal to the master cylinder so the pedal moves an inch or more with no resistance and then contacts the piston to move the fluid. You could obviously drive the truck now that the brakes have cooled off which means something is building pressure in the system and the number one culprit here is usually the actuator rod.

 

Thanks Evan. I will add that to the list of things to investigate/try.

 

All fixed and it was simple, not sure why it happened but it did. All four wheels had a little drag on them when on jack stands, so I adjusted until I heard no brake shoe rub (one of the gurus suggested that) . I then tested the brake actuator from under truck and it had more movement. Took it for a test drive and all good. Good stopping power and no drag!! Thanks for the input guys! Now need to decide if it is time to rewire, I keep putting it off as I have never done something like that. I have rewired a fire control system on a submarine, maybe that counts!

 

Only if you drive your truck underwater.

 

I would have to install a diving alarm, humm may be better then a regular horn!

 

I would buy the inexpensive replacement wiring harness from our host:

Wiring Harness-Generator-Classic Chevy Truck Parts

I installed it in my 1/2 ton over 8 years ago and it has not given me a lick of trouble ever since. The entire harness is numbered and there are clear instructions on how to install it. I liked the harness so much that I also used the same one when wiring my Model A Hot Rod. It adapted easily to that application. Plus, it's really inexpensive as well! Remember to replace the main firewall grommet when doing this job. That is a "must" and it will be the only chance you will have to do it correctly.

Replace the harness on that old truck before something disastrous happens. You can do it in a weekend. It's easier if you remove the seat and seat frame (relatively easy) and if you remove the brake and clutch pedals (even easier). Lying on your back with the seat, pedals and steering wheel in the way is something I really hate to do!!!

Even so, several adult beverages will be required to lubricate the harness and the use of colorful language always helps when wiring as well.

Andy

 

Andy thanks, I have all the parts and the harness you suggest. Our time in Connecticut is nearing an end only a few weeks of time before we fly south for the winter. I think I will put it off until next spring but attack it when I return. Thanks!

 

We have had very good results with both our hosts harness and the $145 Speedway harness. Both have each wire marked and directions for laying out prior to install. An old Bubblehead? USS Permit SSN-594 sister boat of the SLIGHTLY better known USS Thresher SSN-593.

 

I purchased and installed the basic Classic Parts wiring harness and it was easy. Don't rush and triple check each connection.

 

The Classic Harness is really a great choice. I was so excited about it, I helped a good friend install it in his new restoration and wrote this:
AD Truck Wiring Made Easy!

It goes pretty easy as far as harness installations go. Not a bad word to say about it all things considered.

 

Thanks all good to see another bubblehead! Denis

 

Uncle Bill was a Submariner in WWII, lost his sense of smell during some accidental thing .

Anyways , being a Sailor you'll already have the necessary vocabulary to do this important and fiddly if time consuming job .

 

Thanks Nate I will do the job but not until spring. We are snowbirds and after a wee trip to utah we head back to florida so no time to take it on now. Thanks!