Fast forward to Spring 2001. Now the brakes were pulling hard to the right, enough so you had to anticipate and counter steer to the left to avoid going off the road. What could cause that? Well, sticking wheel cylinders. Not at all uncommon, so figured we would replace the wheel cylinders. We weren't sure if we had original 1939 front cylinders (not too likely, based on what's in modern catalogs), but it seemed much more prudent to just get a pair of wheel cylinders -- one for each side -- in the slightly larger diameter used from 1942 to 1948. (If you do have the original wheel cylinders, you can get rebuilding kits with new seals).

Since the truck was pulling right, we decided to look at the left wheel first. When we took the brake drum off though, half the lining of the front brake shoe basically fell out. You can see in this picture of the damaged shoe next to a replacement (and no, we didn't just happen to have the replaceming lying around -- the picture was taken later).

You can see the lining on the old shoe had been riveted while the replacement is bonded. I'm not sure what all the pros and cons are of rivets versus bonding: at one time, the adhesives used for bonding may have been suspect, but I hope the bonded lining won't tear away the way this one seemed to.

I didn't get any detailed pictures of replacing the wheel cylinders or the brake shoes. In some ways it was simpler than "modern" drum brakes since there were no star adjusters, and the brake shoe hold downs are clips on the backing plate. The one part that was tricky was getting the bolts and cams holding the lower part of the shoe in place.

Then it was time to bleed the front brakes, since the new wheel cylinders had gone on empty, of course. Starting on the right side (furthest from the master cylinder) and no problems. But then back to the left side, and the brakes didn't bleed: the pedal was hard even with the bleeder valve open. So maybe the old wheel cylinder hadn't been sticking after all, but something else was stuck in the hydraulic line, preventing the fluid from getting to that wheel cylinder and applying the brakes.

So, remove the flexible hose and try applying the brakes again. Just a dribble out the brake line. There's a junction block very near the driver side wheel, so there shouldn't be that much to clean out or replace. Applying a little more brake pressure with the line open seemed to blast whatever it was out of the line, so reassemble everything; bleed both front brakes again (air might have got into the line past the junction block), and this time every thing seemed good.