Re: Adusting Front Brakes

Posted by Bob Carabbio on November 27, 1996 at 17:53:50

In Reply to: Adusting Front Brakes
posted by Anthony Gal on November 24, 1996 at 17:42:15

If you've got a wheel that's tight (like your E-mail mentioned) and you haven't inspected the condition of the braking system yourself, now might be a good time. An "A" will keep going in spite of the mechanlcal ability of others, but sometimes it's time to check. The CARDINAL rule is that ALL FOUR WHEELS HAVE GOT TO BE DRAWING SIMILAR FORCE FROM THE BRAKE RODS in order for the system to work well. If one wheel is grossly out of adjustment, it will compromize the other four. In order to get the drum off it's safest to loosen the adjuster all the way by turning it CCW. You'll notice it'll screw OUT of the backing plate possibly even showing some threads before the Adjusting head hits inside and you can go no farther CCW. This should loosen up the wheel. If it doesn't there is probably rust on the adjusters and you may have to pound and pry to get the drum off. Try taking off the wheel bearing nut and pounding with a rubber hammer or a block of wood on the drum outer diameter first from the front of the car straight back toward the rear of the car, and from the opposite direction. this should loosen the shoes if they're hung up and allow the drum to come off.
Check the spindle to see if there is wear in the areas that the bearings ride. they should be a smooth sliding fit if they're loose, the spindle is worn and must be repaired or replaced. Check the lining be sure that the rivet heads are not hitting the drum. Make sure the rollers on the ends of the shoe are round and not grooved or flattened. Make sure the roller tracks ("T" shaped pieces located right behind the brake actuating wedge - see illustration in Bratton's catalog in the BRAKES section part #A-2011-C) are in good shape (they probably won't be). The area on the roller track where the shoe roller pin rides is generally pretty worn but can be welded up and filed to shape. By the way if you don't have a Bratton catalog give him a call at (301)253-1929. He has good illustrations and helpful text.
Another thing to check is the condition of the actuating wedge. its tapered sides where the rollers ride should be straight without dents or worn areas.
Check the position of the lever by the Front spring perch that the brake rod connects to. Make sure the brake pedal is all the way returned. The lever should be leaning toward the front of the car about 10-15 degrees. If it's vertical or leans toward the back you are losing range and mechanical advantage on the actuating wedge. It's generally a sign of wear possibly in the actuating rod (that runs through the king pin) which can be shimmed if it's too short.
The Model "A" service bulletins, and MAFCA's "How to restore your Model A" are a good sourceS of DETAILS and procedures. Page's book is largely devoid of details about actually how to fix things. He also wrote primarily about early '28s which were somewhat different.

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