Anyone knowing Buick front brakes with 3 braking pads?

N

nuwala

Member
I need to overhaul the front brakes of my 1933 ? Buick Speedster, the wheel cylinders are leaking and the drums are oval.
Anyone having an idea what brake system this is?

- 11" x 2" drum with 3" pilot hole (cant find any drum like this in the market)
- 3 brake pad system with the lower pad somehow floating
- unknown wheel cylinder, with no article number, it only states FARA, pat 727. It has a 3 bolt pattern
- backing plate has different hole pattern compared to the usual 1942-1952 Buicks. The hole pattern is 5" x 3"

I looked everywhere for days, but could not find the wheel cylinder or the drum. So I though of changing the entire backing plate and pads, but could not find a backing plate with the correct hole pattern either.

Many thanks in advance20240928_174445.jpg
 
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Wow, 33 Buick Speedster, you were just going to change the backing plate just like that?
By discovery of the bore, either measuring the original or looking in the workshop I was able to replace some unbranded chinese wheel cylinders in my vehicle for some USA made branded ones. There are many great resources on this site, with sources for brake parts, the library is my favorite. Of minor detail I think it is "Farat."

Brake shoes look worn too. Usually primary and secondary are different composition. you have center one, wondering composition on that? Can you carefully clean both sides and try to find some brake pad material identifiable markings. They sell shoe material for the DIYer. Also, can get shoes relined. You would probably want to know if shoe material bonded or riveted on?
 
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Well, the ancient design with 3 brake shoes causes a non-linear braking behaviour.

Weak braking is fine, moderate braking cause the lower brake shoe snapping suddenly against the drum, almost blocking the wheel for a brief period. The wheel blocking happening at different times across the front wheels, this causing me slinging across the road almost hitting other cars by accident. This made me think changing the backing plates against the more modern 2 shoe design.

Wheel brake cylinder and drum is so badly worn that honing was rejected by different workshops here in Germany.

Changing the wheel brake cylinder is the preferred solution, but the length (3”) and bolt pattern (1-3/4” x 1-1/3”) is something I failed finding in the market. Therefore, my thought of finding a set of matching backing plates and fitting a standard wheel brake cylinder and standard double brake shoe design.
 
As far as bolt pattern is concerned, a welder can take the backing plate, set it on a piece of copper and fill the holes, clean them up, then drill as required.
 
nuwala said:
Well, the ancient design with 3 brake shoes causes a non-linear braking behaviour.

Weak braking is fine, moderate braking cause the lower brake shoe snapping suddenly against the drum, almost blocking the wheel for a brief period. The wheel blocking happening at different times across the front wheels, this causing me slinging across the road almost hitting other cars by accident. This made me think changing the backing plates against the more modern 2 shoe design.

Wheel brake cylinder and drum is so badly worn that honing was rejected by different workshops here in Germany.

Changing the wheel brake cylinder is the preferred solution, but the length (3”) and bolt pattern (1-3/4” x 1-1/3”) is something I failed finding in the market. Therefore, my thought of finding a set of matching backing plates and fitting a standard wheel brake cylinder and standard double brake shoe design.
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From the image I can see that the center shoe has the greatest wear. If the wheel cylinder is leaking and or rusty from moisture contamination in fluid you will find that it will not apply equally both sides. Very common for the wheel cylinders to freeze on one side from the rust. Why so important to replace the brake fluid sooner than later. Therefore, the application on just one side will cause as you described loss of control braking. Leaking wheel cylinders are caused by the rust that damages the cup seals. Inspect the wheel cylinders and you will see the deep scratches where the rust was the most evident.

How about an 180 degree spin with you facing oncoming traffic at the end of the spin(It happened to me long time ago)? In very similar fashion, low to mid braking no symptoms, hard braking no control.

Anyways, don't be discouraged, you will find the parts. Be patient, it takes that long searching. We all enjoy it as a hobby.

After, you have all your brakes all dialed in, away from all humanity, give it a couple of hard stops, if it doesn't pull or go off to one direction, you are good. Otherwise, if it does pull, reinspect for leaks, and adjustments.
 
Is it not possible to bore and sleeve the existing wheel cylinders? Do they not do that in your country? Is it also not possible to get the drums relined like they do for aluminum units? They would be put on a lathe and cut to fit a liner. This will solve many logistical issues.
Could the third brake shoe be eliminated and the system function as a standard 2 shoe? These are all just suppositions on my part.
 
Another "Wow, a 33 Buick Speedster"! And wow, tapered roller weel bearings. And wow, three brake shoes. I've never seen that before. The bolt pattern holding the backing plate to the steering knuckle looks similar to what was used in 1940 and even 1952 Buick Specials, so my approach would be to check that out. 11x2 brake shoes and drums were quite commonly used for GM heavy duty brakes in full size station wagons. Rock Auto has great detail information in their on-line catalog. I'd start looking for rear brake parts for an 84 Chevrolet Caprice Station Wagon. The wheel bolt pattern for these may even match your hub, which maybe isn't original, with that type of bearing. All the best.
 
Thank you all for your good suggestions.

I managed to get the wheel cylinders honed. The work shop confirmed no rust, but elliptical shape from misaligned brake shoes. After changing a broken aligner spring the shoes seem to be well aligned. The wheel cylinders have not been leaking after put back during the initial 30miles drive.

The workshop confirmed the drums badly warped, already worn to 11.2”, beyond repair. That left me looking another 20 hours without finding a matching drum.

11” x 2” drums are rather common, but no drum with a pilot hole of exactly 3”. I may use a 11” x 2” drum with a larger pilot hole and insert a spacer. Thanks for the recommending rockauto, that’s is a brilliant webpage with the details I was looking for.
 
I think of Rock Auto's catalog as an encyclopedia. It isn't infallible, but it's very very helpful with details and specs. I've had many occasions to wish other suppliers would just copy Rock's pattern. I wonder if cutting a drum's smaller pilot hole larger would be nicer than using a spacer. ("Choose your pain.")
For those of us who like the idea of changing from ball bearings to roller bearings like yours, would you please post the part numbers? There would be four, one on each part. (Inner race, inner cup, outer race, outer cup)
And just for me, myself, and I, would you please post a picture of the Speedster? I have very little idea of what it is, and would like to see it. (I know, I'm just being one of those "high maintenance" guys.)
Thanks, and happy braking.
 
oldfoneguy said:
Is it not possible to bore and sleeve the existing wheel cylinders? Do they not do that in your country? Is it also not possible to get the drums relined like they do for aluminum units? They would be put on a lathe and cut to fit a liner. This will solve many logistical issues.
Could the third brake shoe be eliminated and the system function as a standard 2 shoe? These are all just suppositions on my part.
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I never knew about relining the aluminum drums. What can you tell us about liner availability?
 
The roller bearings in my Speedster are Timken F2382 and F2554. Not sure if that would fit a standard Buick, the roller bearings are for a hub with central wheel lock system. This is how the car looks like:

 
Stray Tate said:
I never knew about relining the aluminum drums. What can you tell us about liner availability?
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I don't know much of the process just that it was done at one time. The liners were premade items.
It was more common in the 70's when the aluminum drums were getting old but still commonly in use.
It may be a lost art today. Sadly there is a big difference in call for the process from when these were daily use items to today as "collector specialty" items.
 
The closest to the original brake drums are rear drums from a VW ID3 - yes the EV. Everything fit, except for the hub hole which was widened to 3" on a lathe. I'm driving now a VW - Buick :)
 
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nuwala said:
The closed to the original brake drums are rear drums from a VW ID3 - yes the EV. Everything fit, except for the hub hole which was widened to 3" on a lathe. I'm driving now a VW - Buick :)
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Does your Hybrid get better fuel economy now? (I make small joke.)
 
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