MTFCA Forum

Good day everyone
I have a new to me 1911 touring with AC Brakes. They are seriously out of adjustment. Could someone give me instructions on how to adjust them?

a useful reply will come quicker if you let readers know if it is rod or cable operated, and if the mechanism includes an equalizer arrangement or not. Once that is known, then instructions will be short and accurate.

Good day everyone
My AC brake has rods, no cables. Also no equalizer.

Not the definitive answer, but here's what I would do:

1. Jack up the rear of the car so that the rear tires are off the ground. Loosen the trans brake band so that it doesn't interfere with the setting of the AC brakes.

2. Put the car in neutral (hand brake lever vertical).

3. Back off the AC brake adjustment at each wheel.

4. Check to make sure that the wheels don't drag due to incorrectly adjusted emergency brakes. Adjust the emergency brake rods if needed.

5. Tighten each AC brake at the rear so that its wheel is locked solid with the brake pedal up (not being depressed).

6. Loosen each AC brake adjuster the same number of turns until the rear wheels turn as freely with the brake pedal up as they did after step 4.

7. Have an assistant press the brake pedal and verify that the AC brakes can lock each wheel solid. If one side locks after the other, tighten up only the loose side until they both lock together.

8. Adjust the transmission brake band so that it grabs only when the brake pedal is exerting maximum force. That way the AC brakes do the work most of the time, but the trans brake can help the AC brakes on panic stops.

Good luck!

Thanks.
Should I disconnect the brake rods after step 2. Then reconnect after step 6?

Can't hurt. Just make sure that the rods are adjusted so that when everything else is set, the pivot pins slip in without changing the position of the various levers.

Mark

That is one of the best explanations I have ever seen. Thank you.

Question. How do you adjust the transmission brake after the ac brakes are set?

RGould1910 wrote: ↑

Sun May 07, 2023 3:47 pm

Question. How do you adjust the transmission brake after the ac brakes are set?

Disconnect the brake linkage & adjust the internal brake band as without. Adjust to engage @ about 1/2 travel. The a/c's or R/M's should engage just before the trans brake. I have brakes directly on the small parking brake drum. On full braking they work together & will LOCK the rear wheels when necessary.

Good day everyone,
I got to play with my AC brakes yesterday. I found something interesting that I didn’t expect. Not sure I can describe it but I’ll give it a try.

The AC brake shoe mounting bolt divides the shoe into an upper half and a lower half. The upper half is attached to an adjusting nut. The lower half is attached to the brake rod. When I disconnected the brake rod the lower half of the shoe fell away from the brake drum. The length of the brake rod controls the engagement of the lower portion on the brake shoe.
So I adjusted the length of the brake rod to make the lower half of the brake shoe too tight then back off a two turns.

The next step was to tighten the upper part of the brake shoe. By using the adjusting nut I made the upper half of the brake shoe too tight then back off two turns.

I haven’t driven this car yet. It’s still up on jacks. But this seems to work. Or, am I missing something?
Bye for now.

Sounds right to me, let us know how the brakes work with the adjustments you made. Are your AC brakes original, or the newer Larry Sidmore reproductions? If you're using rods then It's likely you have the reproductions, the originals were cable actuated.

Good day everyone,
I believe my AC brakes are the reproductions. I used Cudamans eight steps. I did adjust the brake rod length to get the lower half of the brake shoe right then used the adjustment nut to get the upper part of the brake shoe right. Drove the car yesterday and the brakes worked fine.