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Hi,
before I take the car apart I would like to know if anyone has encountered this similar problem. When I apply the brakes my right front brake makes a "Clunk' noise. With the parking brake on when I rotate the wheel is feels as if the shoes are rocking with the drum, then stop moving. I had the shop that rebuilt the engine check all the brakes and the front drums were turned and the shoes relined. There was a bit of a time crunch to roll the car out of the shop because the shop owner died just as the engine rebuild was finishing up. This brake also locks up when the pedal is pressed hard. I am collecting all the information here and studying my service manual. My experience with mechanical brakes is extremely limited. Thank you for any help.

With the parking brake on when I rotate the wheel is feels as if the shoes are rocking with the drum

No reason to feel intimidated by the Bendix mechanical brakes, nothing counterintuitive.

Just for starters if you can rotate the wheel with the parking brake applied the shoes are way out of adjustment as the parking brake actuates all 4 wheel brakes. I'd pull the drums to make sure everything is reassembled correctly and lubricated; consider removing the cable sheaths and lubing the cables internally with a good graphite grease such as Sta-Lube SL 3303 if they haven't been done in recent memory. Then with the cables dropped do a thorough major brake adjustment per the Service Letter; don't ignore the eccentric adjustment - always a requirement when new shoes have been installed. Then reattach the cables, lengthening or shortening if necessary such that the clevis pin just enters the actuating levers. It's all in the Service Letters in good detail.

Then perhaps do a road test, its a pretty primitive test, preferably on dirt or gravel so you can "read" the wheel drag on each wheel and make further adjustments. Remember, the left front wheel has narrower linings to compensate for the trunnion block so on light pedal pressure a very slight pull to the right would be expected but not on a heavy brake application. I trust the guy who relined your front brakes was aware of the different lining widths front left and right.

However an alternative I use to get a very close static adjustment is with the cables dropped and the small "window" removed from the drum so you can use a feeler gauge between the shoes and the drum and adjust according to the service letters. Then adjust the lengths and attach the cables and use a jack or similar and apply partial pressure to the brake pedal - then go around and check each wheel individually and adjust at the wheel until you have uniform drag at each wheel. Crank the pedal down a bit tighter and readjust if necessary.

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Thank You for all the information. My car is back on the ground, the brakes are adjusted and everything is working nicely.

That could be anything from a loose backing plate to worn spring shackle pins and bushings to loose spring anchor u-bolts to a sticking cable to a worn out drum. If you pull out the manual there is actually entire list of items to check for front suspension problems.

When the linings were redone they should have been fitted to the drum diameter. If linings are replaced and drums put into a lathe without assessing drum wear the results are likely to be poor. Pickup trucks with rear drum brakes often suffered the malady of premature lock up due to worn drums. The solution was new drums and shoes.

Perhaps the car has a gypsy drum on it as well. I would measure the drum diameter of both sides to check for congruency. Ideally they should be within .010 of each other.

If the drum itself is shot the shoes can be shimmed to fit until such time as a better unit can be found.

AJS,
Just curious. What was the problem and how was it corrected?
Joe

Late reply....
The problem is 95% better. I adjusted all the brakes and cables. This only corrected the problem a little bit. I had a friend riding in the back of the car and when applying the braked he heard the clunk noise, but he said it was from the rear of the car. I reinspected everything and after thinking about it for quite some time recalled that there was quite a bit of slack between the brake booster and the arm that it pulls on. I suspected that the clunk might be the cable snapping as the booster pulled on it, I tightened the cable to reduce the slack and the result is the car stops very nice with no clunk.
Andy