1949 Ford Front Brakes Locking Up

C

Colin S

Junior Member
I have a 1949 Custom Sedan built in Belgium with the 6 cylinder engine. The car is totally original with 77,000 kms ( 48,000 miles) and all original paint, chrome, glass and upholstery. I bought it out of long term storage and did all the usual things that it needed including a rebuild of the brake hydraulics. It has driven well for several years but has developed a problem. If I so much as touch the brake pedal the front wheels lock up and throw the occupants against the dash panel as the car screeches to a halt.
These were never sold in the UK and the knowledge is sparse. The linings all look OK but as they are bonded to the shoes I assume that they are replacements. The parts book shows that the primary and secondary shoes have different linings and from my knowledge of Lincoln-Zephyrs I know that they have one moulded lining and one woven. Is this the case with the 1949 Ford? Does anybody have any idea as to where original type linings could be found? The car is now too dangerous to drive. Thank you for any advice. I will be at Hershey in October.
 
Colin, are you in the UK? have you used Rockauto? I just looked up those shoes and a set of riveted ones to the uk with duty and vat paid would be about £40. I have used them many times for things like this.

They're good for things like wheel cylinders, master cylinders and hoses etc.

PM me if you want me to tell you what you need to do.

Mart.
 
It may not be the shoes at fault. Be certain that the brake return springs are in correct locations. Be certain the primary & secondary shoes are correctly installed. Make sure that the shoes are properly adjusted for centering to the drum and for light friction drag at full retraction. Last but not least, check the master cylinder for signs of blockage of the flow and return ports in the bottom of the fluid reservoir. If either one is blocked or even partially blocked, it can cause problems. If fluid can't properly return then the brakes can stay applied for a time. If nothing shows defects to this point, it may be a good idea to check the wheel cylinders for signs of sticky pistons. If it pulls badly to one side, a person can sometimes narrow it down to a particular wheel cylinder if the problem lies there.

I hope you can find the cause. No brakes are no good and so are stuck brakes.
 
It sounds like they worked OK for a while and then developed this problem while in use. If that's the case, I would suspect some kind of contamination rather than a mechanical problem, especially if the shoes are not badly worn.
 
Be sure you have enough free play at the brake pedal to allow the master cylinder to full retract. Otherwise the fluid can't fully return to the reservoir, allowing the wheel cylinders to build pressure. If you have the free play, it is likely the residual valve in the master cylinder is stuck. If only one side of the front brakes stay on, the rubber hose to that side is plugged.
 
Thank you for all you very helpful advice. All the hydraulic cylinders, hoses and steel lines were replaced after the long storage and are now less that 5 years old. I will check that the springs are all correct and the shoes are centered.I think that I have suffcient free play on the pedal and I did adjust it to the maximum thinking that this might be the problem. It now seems most likely that the shoes may have been comtaminated at sometime in the past and simply cleaned and re-used. While I am in the USA I will try to get a new set of shoes. I am still not clear as to the difference between the primary and secondary lining. Woven material on the secondary and moulded on the primary as with a Lincoln-Zephyr ? Thank you all for your most valuable input which is very much apprecated.
 
I am still not clear as to the difference between the primary and secondary lining.


They could either be of different type of material or some cars had different
length of lining material.


Bob
 
This should help.
 

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There are generally just different length & placement for the primary (front) & secondary (rear) shoes on a Bendix type system. The primary starts the braking action by its rotational movement and the secondary follows actually performing most of the braking action against the drum. Referred to as dual acting brakes, the Bendix design was a lot better set up than the previous Lockheed design that Ford used till 1948 on cars. You just have to make sure the shoe with the smaller lining size in on the front side.
 
The chamfer at the ends and that they are adjusted tight enough...if they are loose they lock up.
Tighten up until they drag...more then you really want them to feeling good about it ;)
Take it for a test drive and they will be just perfect when home again...
 
Thanks for all the additional information and for the explanation of the difference between primary amd secondary linings. I have checked out the linings on the car which are clearly replacments and they are both the same lenght but do have chamfers are both ends. I will re-adjust the brakes as suggested to bring them closer to the drums. I am sure that I will be able to find some more original linings or complete shoes while at Hershey. Again thanks to all who have offered advice.
 
Do you have apart look it or just getting suggestions? I am wondering if you have any bearing grease on the linings.
 
Check the drums for cracks. A cracked drum will expand when the brakes are applied and lock the wheel. I had this occurrence on the rear of my sedan delivery. the problem was cured with new drums.
 
The linings are dry and free of any grease. The drums don't have any visable cracks but I will check further. Thanks for the valuable suggestions. Looking forward to Hershey having not made the trip last year.
 
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