1934 Plymouth Brakes

[Solly]

 Here I am again !

Hope you don't tire of me. I thought there was room for improvement on Fanny Mays brakes, I did not pull the wheels or drums  since the previous owner assured me  the brake shoes were new on all 4 corners and he was truthful on everything he told me so far and it is obvious after visual inspection that all the wheel cyls and brake lines and master cyl have been replaced but that being said I thought the brake pedal was a little low so I did a 4 wheel brake adj I did not have the fancy tool so often recommended so I just went old school drag method I was again amazed at the simplicity !! cam and jam nut also amazed again that nothing was frozen, everything operated as designed. I simply adjusted the cam till the wheel dragged then backed it of a smidge till free all 8 shoes. This did improve the pedal but I still think there is room for improvement once I have a competent assistant im going to bleed them then if I'm still not satisfied I may try adjusting the rod between master and pedal (keeping in mind the pressure switch not be activated when pedal not depressed)

 Im not so naïve that I believe these 1934 brakes should operate as well as modern brakes but I think I can get them a little better. The brake rod is a last resort as that is a tight squeeze down there kind of congested with  clutch pedal mechanism.

 Any pointers or tips from the knowledge base here will be appreciated.

 

 Thanks Solly

[TodFitch]

It sounds like you understand how these brakes work and how to adjust things.

 

One thing you did not mention was checking to see if the shoes have been properly arc'd to match the drums. That makes a huge difference in how much shoe makes contact with the drum when braking and thus how effective they are. If the lining material is fairly soft they can wear in after a reasonable number of miles. But it seems to me that a number of modern shoe lining materials take a long, long time to wear in and if you want better brakes in your lifetime you should assure they are arc'd properly.

 

In the old days there were shops with shoe grinders that would do this work. Outside of a few hobbyists or hobby related businesses that service and those tools are pretty much non-existent today.

 

What I did was find a roll of sticky back sand paper at my local hardware store, I am not sure what tool(s) it was intended for, but it fit my needs. It was a few inches wide and way longer than I needed. At each wheel, I took the shoes off, marked across the face of the lining with a sharpie so I could track progress, cut sandpaper to fit in and stick to the inside of the drum. Sticky side to the drum surface, rough side to the inside. Then I rubbed the shoes around the inside of the drum until the sharpie marks were gone. Remove the sandpaper from the inside of the drum, reinstalled the shoes and drum, did the major and minor adjustments and moved to the next wheel. This made a big difference in how well the brakes on my '33 work. Still a far cry from modern brakes, but a lot better than before I spent a few minutes on each wheel with the sandpaper. And it really was just a few minutes, removing and re-installing everything took longer than the actual arcing of the shoes to the drums with the sandpaper..

[Dave72dt]

You can find that sticky backed sandpaper at body shops or auto body suppliers.  I comes in rolls  or individual sheets 2 3/4" wide x 16 1/2", varying grits.

[desoto1939]

Solly:  Remember that you will not get a real hard pedal like to now have on your modern cars. There is always some travel distance when applying the brake pedal and how the pushrod moves.  Before making any adjustment on the pushrod please refer to your factory service manual in the brake section. It will tell you the distance of the free play for your car.

 

Also remember that you are dealing with a braking system that was designed in the early 1930's.  You have to have a mindset of this when driving your car now in the modern times and the reaction of brake fade in these old cars is a known factor.

 

I have a 39 Desoto with the 11 inch brakes. Yes, I can stop my car but I always anticipate a potential stop when approaching an intersection that is controlled by traffic light.

 

When approaching a light and it is green and I see a bunch of cars coming towards me in a group then I assume? that the light has recently turned green for my oncoming traffic.  If there is a lot of space between the cars or only a single car in a row then I assume, Again, that the light will be turning to yellow and then to red.

 

You always have to have your mind and driving skills in tune with the od antique car and how it reacts to your driving and to the appropriate driving situation. 

 

Rich Hartung

desoto1939@aol.com

[Ivan_B]

21 hours ago, TodFitch said:

One thing you did not mention was checking to see if the shoes have been properly arc'd to match the drums.

I bet they weren't arched, neither were the drums checked for proper condition... No one does these anymore... I am planning to do mine, as well, as soon as I manage to defeat my laziness to take the drums off The brakes work okay, as is, but I do have to press it a bit harder than I should in order to stop when rolling downhill.

[westaus29]

As well as arcing the shoes, make yourself one of those fancy tools (or fork out $100 to buy one from a mopar supplier) and adjust the brakes properly. The early Chrysler brakes have fixed pivots and need to be adjusted both at pivot and cam.

 

[Solly]

On 12/4/2024 at 2:25 PM, desoto1939 said:

Solly:  Remember that you will not get a real hard pedal like to now have on your modern cars. There is always some travel distance when applying the brake pedal and how the pushrod moves.  Before making any adjustment on the pushrod please refer to your factory service manual in the brake section. It will tell you the distance of the free play for your car.

 

Also remember that you are dealing with a braking system that was designed in the early 1930's.  You have to have a mindset of this when driving your car now in the modern times and the reaction of brake fade in these old cars is a known factor.

 

I have a 39 Desoto with the 11 inch brakes. Yes, I can stop my car but I always anticipate a potential stop when approaching an intersection that is controlled by traffic light.

 

When approaching a light and it is green and I see a bunch of cars coming towards me in a group then I assume? that the light has recently turned green for my oncoming traffic.  If there is a lot of space between the cars or only a single car in a row then I assume, Again, that the light will be turning to yellow and then to red.

 

You always have to have your mind and driving skills in tune with the od antique car and how it reacts to your driving and to the appropriate driving situation. 

 

Rich Hartung

desoto1939@aol.com

Thanks gentleman,

After a adjustment and bleed on all four corners the brake pedal has improved. I'm not expecting modern era brakes I just thought I could improve on them a bit as well as making myself more familiar with my new car as well as its adjusting procedures I figured that the only way I could screw it up was to get them to tight and after 25 years as a ASE certified tech I knew that wasn't going to happen, however once again Pre- war cars  are new to me so the learning goes on. As A side note I noticed the abundence of Zerk fittings a Zerk for everything !! I think the Zerks have Zerks !!! also noticed several places where things  (bearings) can be oiled with a oiler !! I will start diving in to the newly delivered Master Maintenance manual for service intervals. 

 Thanks for the suggestions and help, Im sure I will be leaning on you more. P/S I will tailor my driving habits to the car as suggested .I did it on my Olds I will do it for this car as well ( still working on the double clutching and allowing the gears to slow me down as opposed to engaging the clutch to early )

[TodFitch]

1 hour ago, Solly said:

still working on the double clutching and allowing the gears to slow me down as opposed to engaging the clutch to early

Two things help a lot: First, make sure you have something close to the summer weight gear lubricant recommended in the manual in the transmission. That makes a huge difference in shifting.

 

Second, when up shifting you will want to be in high by 15 or 20 MPH. 25 MPH tops. First and second are really just to get you started, almost all the time you will be in direct. None of this revving up in all the gears for maximum acceleration you are used to on much later cars. Back then it was all about the engine being quiet and smooth at low speeds.

 

For down shifting, all I can suggest is practice, practice and more practice. It helps if the vehicle is going slow, remember you will be in high down to 15 or 20 MPH. Trying to double clutch downshift at higher speeds it really hard to get right.

[Dan Hiebert]

Just a thought, may not apply since the work you've done has improved the braking, but do you know what type of brake fluid is in the car?  As in DOT3 or DOT5?  I imagine you know the difference, but whether or not the PO told you what's in it is another story. 

[Ivan_B]

On 12/7/2024 at 8:42 AM, TodFitch said:

Second, when up shifting you will want to be in high by 15 or 20 MPH. 25 MPH tops.

I just checked my P10 manual, and it says exactly that: shift 1-2 at 10, and 2-3 at 20. I was shifting 2-3 mostly around 25, especially when going up the hill. Need to adjust my driving technique 😐