Brakes Not Stopping The Car

mgtf1500

mgtf1500

Junior Member
This started last week. When I brake going downhill (slowly) the car does slow down to a walk, but the brakes won't fully stop the car. It will coast to a stop on its own with me standing on the brake pedal.. How to adjust? The drums and shoes are relatively new. I'll take all ideas.
 
It's hard to put the whole procedure in writing. do you have any technical manuals or brake books? They will stop your car quickly and surely when all components are restored to new condition. The adjusters at each backing plate runs the shoes closer to the drum so you might start there.
 
A good initial adjustment takes some time and effort. There is a lot of info on this in search. There are a couple methods that will give good results. [ and a couple that won't].
 
Definitely time for an adjustment. I believe the proper procedure is described in the service bulletins. If you don't have them it's worth buying a copy.



It isn't hard to get the brakes adjusted well, just have to follow the proper procedure and take your time.
 
In my opinion you either need to find an experienced mentor that KNOWS how to correctly work on Model-A brakes, -or you need to find a professional that is experienced with these. In this day and time, you don't need to take a chance on poor-performing brakes. The mechanical brakes on your car should be able to make nine (9) 40mph to 0mph panic stops in a row, -and on the 10th time they should be able to slide all 4 wheels at 40mph with the pedal no less that a ¼ way off the floor. If they won't do that, then they need work.
 
The brakes have a lot of pivot points that can wear slowly over time. If this happened all at once I would check all the hardware before taking the drums apart.
If you have any sandy places near you I would try locking the brakes and then look at the pattern. It might be one brake failed.
 
Here is how I adjust mine . I start with the center service brake cross shaft . I dis connect the service brake rods on the adjustable clevis ends . I set the pedal rod so that the plunger end is 1/16th of an inch from the inside rear of the center crossmember where it meets the plunger on the brake light switch on the 30-31 models . I then adjust the clevis on the pedal rod so that the pedal is at the top of its travel and prop it up until you get the service brake rods adjusted and connected . I then adjust the adjusting wedges at each wheel until there is very slight drag but the wheels will turn fairly freely . I then adjust and connect the service brake rods so there is no slack where the clevice end connects the brake levers . I pull the front brake levers back to remove all slack . I then adjust the front service brake rod clevises so that the brake rod pins will JUST enter the clevis and front brake levers . I then move on to the adjustment and connection of the rear brake rods . Pull the rear brake levers forward to remove the slack and then adjust the clevices so that the brake pins will just enter . This setup will remove all of the slack in the brake rod connections so that the brakes will be ready to begin activation with the least amount of depression of the brake pedal . This is only the setup and adjustments . If everything is good with the brake drums and other parts under the drums are in fairly good shape you will have good brakes . I always test mine in a sand or dirt driveway to observe the skid marks and readjust as necessary .
 
Purdy Swoft said:
Here is how I adjust mine . I start with the center service brake cross shaft . I dis connect the service brake rods on the adjustable clevis ends . I set the pedal rod so that the plunger end is 1/16th of an inch from the inside rear of the center crossmember where it meets the plunger on the brake light switch on the 30-31 models . I then adjust the clevis on the pedal rod so that the pedal is at the top of its travel and prop it up until you get the service brake rods adjusted and connected . I then adjust the adjusting wedges at each wheel until there is very slight drag but the wheels will turn fairly freely . I then adjust and connect the service brake rods so there is no slack where the clevice end connects the brake levers . I pull the front brake levers back to remove all slack . I then adjust the front service brake rod clevises so that the brake rod pins will JUST enter the clevis and front brake levers . I then move on to the adjustment and connection of the rear brake rods . Pull the rear brake levers forward to remove the slack and then adjust the clevices so that the brake pins will just enter . This setup will remove all of the slack in the brake rod connections so that the brakes will be ready to begin activation with the least amount of depression of the brake pedal . This is only the setup and adjustments . If everything is good with the brake drums and other parts under the drums are in fairly good shape you will have good brakes. I always test mine in a sand or dirt driveway to observe the skid marks and readjust as necessary .
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Purdy, I hope you have you're write up saved somewhere on your computer so you don't have to write it out each time. :p I have seen you post this numerous times in the past.

Follow Purdy's advice and you should have good stopping power.
 
mgtf1500 said:
This started last week. When I brake going downhill (slowly) the car does slow down to a walk, but the brakes won't fully stop the car. It will coast to a stop on its own with me standing on the brake pedal.. How to adjust? The drums and shoes are relatively new. I'll take all ideas.
Click to expand...
If I am reading this right the brakes were fine and then all of a sudden they didn't work very well. I would check to see if a clevis pin fell out and one brake rod is not attached. Did you do ANYTHING shortly before you noticed the problem? I once opened up some rear brakes only to find that a service person had pumped the entire backing plate cavity full of grease. No knowledge and a pressurized grease gun are not a good thing. Did you have the car serviced shortly before the problem started?

Charlie Stephens
 
Charlie Stephens said:
........ Did you do ANYTHING shortly before you noticed the problem? I once opened up some rear brakes only to find that a service person had pumped the entire backing plate cavity full of grease. No knowledge and a pressurized grease gun are not a good thing. Did you have the car serviced shortly before the problem started?

Charlie Stephens
Click to expand...


ditto. I have found the same over greased rear hubs.
 
Remember, you have an Emergency Brake and if you 'hold the top button down' as you pull back on the lever, you should be able to stop the car over distance.
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[FONT=&quot]As another reply noted, If at all possible, THE BEST THING is to get the advice of experience from someone near you. Try and find someone/group near you to help you and make new friends at the same time.[/FONT]
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[FONT=&quot]I would advise that at the very least you acquire a good Model A Shop Manual and/or a service manual if you do this yourself. There is a spec. for a 2x4 wood block cut-out that I found on this forum long ago. Some may still have that info.
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[FONT=&quot]ALL of the following is predicated on the understanding that your linkage is tight and adjusted evenly and correctly, especially the 15 degree front angle to start and as you say your shoes are relatively new.
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[FONT=&quot]'NOTE' - as a 'hard' rule the brake pedal should ALWAYS be no less than four (4) inches from the floorboard when the brake pedal is fully engaged and quickly pressed to come to a full stop.
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[FONT=&quot]In any event, here is advice on one way to adjust your brakes - takes two people[/FONT]
[FONT=&quot]A quick way is to first, jack up the front of the car (both wheels suspended and spin free). While the Model A has lots of ground clearance it is always advised to use jack stands as well.
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[FONT=&quot]Begin to spin one of the front wheels as you turn the 1/2 square adjustment bolt 'clockwise' one click at a time (found on the inside back-plate). Once you hear/see/feel the brake engage and slow the wheel, turn it back one or two clicks - these are actually notches you can feel with your wrench.[/FONT]
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[FONT=&quot]Next, go to the other front wheel and do the same thing (again, use jack stands). Then spin both front wheels at about the same speed and have someone firmly press the brake pedal and see if the two wheels slow and stop at the same time.
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[FONT=&quot] If so, then take the car for a short test drive (in an empty parking lot) and holding the steering wheel slightly, push firmly on the brakes to see if the car pulls to one side or the other. If it does, adjust the opposite side (clockwise a click or two) and repeat the drive until correct.[/FONT]
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[FONT=&quot]Then do the same for the rear wheels. The rear wheel brakes should generally engage directly after the front brakes. If you have calibrated the front brakes correctly, this can be checked by jacking up one side (front and back) and spinning the wheels and then having someone firmly press the brake pedal as you observe the braking of the wheels
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[FONT=&quot]Adjusting the Emergency brakes is a process involving the linkage.[/FONT]
 
I wonder if you do didn't have the new breaks trued to the hub when first installed. If not, you could have worn the high spots and now have less breaking against the drums. Might be as simple as a bit of adjustment needed. Try the procedure purdy mentioned and see if you adjustments were off before.
 
Being as I only discussed adjusting wedge and brake rod adjustment in post number eight , here is how I check and adjust for the 15 degree forward lean on the front brake levers . I adjust the square adjustment wedges behind the brake backing plates for a very slight drag that can just be felt . With the front brake rods disconnected I then pull back the slack on the brake levers and observe the front brake levers to check that the levers lean forward around 15 degrees . If the levers don't lean forward the desired amount its time to let off on the adjustment wedges and remove the brake drums for access to the front brake push rods or sometimes called operating pins . The pins should be seven and one quarter inches long. If the push rods are worn too short it will be necessary to replace with new unworn parts or build the push rods up with weld for correct length . I have sometimes used brake pills-shims to force the levers to the 15 degree forward lean . If it takes more than three pill-shims per side I would either replace or build up the pushrods to the correct seven and a quarter inch length . If removal or replacement of the push rods is necessary it will be necessary to remove the front lower operating wedges for access .
 
mgtf1500 said:
This started last week. When I brake going downhill (slowly) the car does slow down to a walk, but the brakes won't fully stop the car. It will coast to a stop on its own with me standing on the brake pedal.. How to adjust? The drums and shoes are relatively new. I'll take all ideas.
Click to expand...

I second joining a local club, if you have not already.
Absolutely invaluable resource, and I can bet that someone would be more than happy to come out and help you set them up the correct way.

There are two MARC clubs close to you:
20 minutes away
MODEL A DRIVERS OF EAST CENTRAL OHIO
10010 HERON DR
THORNVILLE, OH 43076 C/O JIM ZIMMER
614-353-8236
rebecz@aol.com

58 Minutes away
ENTRAL OHIO REGION
PO BOX 161
COMMERCIAL POINT, OH 43116 C/O ALLAN GOLDHARDT
614-877-3888
goldhardt@ampritech.net
http://www.themodelaclub.org

If you don't have these two books, you should buy them as they both detail how brake adjustments should be done.
SERVICE BULLETINS:https://www.snydersantiqueauto.com/ProductDetail/BP-1_MODEL-A-SERVICE-BULLETINS-BOOK?fromCategory=Products/books/model-a-books
MECHANICS HANDBOOK VOLUME 1:https://www.snydersantiqueauto.com/ProductDetail/BM-2_MODEL-A-MECHANICS-HANDBOOK-VOLUME-1-BOOK?fromCategory=Products/books/model-a-books
 
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