Brake problem for 1964 F-250

I need some help. I am out of ideas. My driver’s side rear brake locks up causing the truck to swerve to the left. I have re-built the entire brake system. I replaced (with new parts) the shoes, drums, brake cylinders, brake return springs, brake adjusting springs, and the hold-down parts. I completely flushed and bled the system. The adjuster has been screwed all the way down. Still, the rear brake locks up. What am I missing?

 

please don't take offense, but could your brake shoes be on wrong? The primary shoe (shorter brake material) should be in front and the secondary (longer brake material) in the back relative to one another

 

No offense taken. I'll check that. At this point I'm open to all possible causes. Thanks

 

You may also want to check that the other side doesn't have a leaking axle seal. I had that issue with my right rear locking up. The left shoe was completely soaked in gear oil. Also I didn't notice if you list any rubber lines. If your truck turns hard to the left you may have a swollen front right rubber line. That was discovered during my swap to disc brakes. The wheel would almost be ripped out of my grip when I stomped on the brake pedal. The exterior of the line looked a little faded but was clogged from rubber and rust particles. I know you can still get the stock rubber lines all the way around (all 3) for $100 or less from most part stores.

 

I didn't include it in my original question, but I did replace all three rubber lines. The rear steel brake lines are original, but I flushed and bled them. I may need to blow them out under pressure.

I have new brake shoes, with no visible stains.

Thanks for the suggestions.

RBK

 

Still running the single master cylinder?

 

No. I did a power brake conversion with a Master Power conversion kit. The kit includes a dual master cylinder, with built in proportioning (no additional proportioning value needed between the front and back brakes.) It seems to be working well, except on the one wheel. Both the rear wheels are on the same rear brake line.

As I go back and re-check, re-work each thing that has been suggested, it seems to be improving some with each step. I think I may have a bunch of little things all added together causing this.

The last thing I did was I re-adjusted all four brakes from scratch this morning. Now, most of the drag is gone. The more I drive it, the better it seems to be getting.

Is it possible that one of the shoes or drum had a "glaze" (or some contamination that wasn't clearly visible) on it, or other wise need to be "broken in"???????? (They were new (not rebuilt) Raybestos riveted shoes. The drums are also brand new from Raybestos.)

I guess the punch-line is that it is now drivable.

RBK

 

did you get the conversion kit for drum front/drum rear? I think that the proportioning valve would be different (or adjusted differently) for disk front/drum rear

 

Yes, it is the drum/drum kit.

RBK