VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 suddenly no brakes

I started to take my '41 sedan out of the garage and noticed that the brake pedal went straight to the floor. The brakes seemed fine a few days ago and I don't see a lot of fluid on the garage floor.

Is there something that I can do to safely get the car to a mechanic? I live on one of the beautiful ridges surrounding the city and don't want to damage me or the car.


I'm a car mechanic novice and appreciate your replies. Thanks.

Your first task is to lift the mat under the drivers feet. In the floor you will find a round rubber stopper. Remove this stopper/plug. Now the mastercylinder will be exposed. Remove the cap and check the fluid level. If dry or low, put in some fluid and see if that corrects the problem.

YOUR JOB IS NOT OVER. YOU MUST FIND WHERE THE FLUID WENT AND REPAIR THE PROBLEM.

call a wrecker with a rollback . you may try filling the master cylinder with fluid and see if they will pump up . you will have this problem until you have the wheel and master cylinder sleved and new kits installed . a frend of mine had this happen to his 41 a while back he took it to his mechanic i gave him this advice but his mechanic said he would replace the cylinders with new and they would be ok and it was for a short while and back to the old routene that is whats good about mechanical brakes if they work when you put it up they usally work when you go to use it may have to lub it

Agreed on filling the master cylinder if it's dry. Then try to pump it up. If you've blown a line you'll be able to track it down from where the fluid as puddling. The positive battery cable wore a hole in the brake line on my 38. I knew exactly where to look when I saw the puddle.

OK, I found the filler plug. It's medal not rubber. Does it have a screw or should it just pull out. I did not want to try and force it. Thanks.

I can't get a wrecket to my garage. Thanks for the info.

The plug you removed from the floorboard is metal/rubber. The cap to the master cylinder is metal. It has a square top that can be easily removed with an adjustable wrench held vertically and turned with a screwdriver through the hole in the wrench.

If it still fails to budge you may have to work from below with the adjustable wrench.

It does not need to be torqued on, just snug.

You may not like the looks of the "stuff" you find in the bottom of the master cylinder. If you decide to tackel the problem, it is strongly recommended you have your own master cylinder and all 4 wheel cylinders bored and lined with brass/stainless. Install new kits after blowing out all lines, reassemble and use fresh brakefluid and you will have a sound set of operating brakes.

OK, I follow you. Thanks for the tip on the screwdriver through the hole in the wrench.

The master cylinder is dry. It actually looks pretty clean; maybe stainless. Is it reasonable to expect that I could add brake fluid and get it safely to my mechanic. I need to go about 10 miles, starting down a ridge that is about 700 feet high with windy streets?

Do you have to send the master and wheel cylinders off to have them bored, etc.?? If so, do you have a recommendation.

Thank you for your help.

How good is your parking brake? Just kidding...If it were mine, I wouldn't drive it. Fill the reservior and put the cap back on. Then you look underneath the car while a beer buddy depresses the brake, you should see fluid fly out of the leak, or at least bubble. Fix that, then take it to your shop to have it repaired. NAPA has proven themselves to be quite competent when it comes to old stuff like that. If they don't do it in your particular store, they will ship it to the district controller who will have it done, pretty affordable as well.

Thanks everyone for the info.

A question; to the left of the opening in the floor for the master cylinder, there is a smaller hole that gives access to a medal bolt. Could you tell me what that is?

Thanks.

The mastercylinder is bolted to the frame with two bolts. Perhaps you see the head of one of those bolts?

I have just returned from a trip out of town for a few days and read of your brake problem. I am surprised no one has told you about bleeding the brakes. If your master cylinder was dry, the fluid had to leak out somewhere and you do need to find the leak. However, just filling the cylinder with more fluid and pumping it will not activate the brakes. Once a master runs out of fluid, air will get into the lines. This air has to be purged before the hydraulic system will work properly. To purge it, you would do best to have a helper. Once you fill the master cylinder with fluid and replace the top, someone needs to press on the brake pedal as each wheel cylinder bleed screw is opened to allow the air to escape. It is best to place a small hose (preferably clear plastic) on the bleed screw and run it into a little brake fluid in a clear jar. That way, you can see when the air bubbles stop and fluid actually flows from the bleed screw. The purpose of putting a little fluid in the jar is that once the air is out of the line and some new fluid has flowed into the jar, air cannot get back into the wheel cylinder if you have the end of the hose under the surface of a liquid. Once the new fluid flows, tighten the bleed screw. You have to add more fluid to the master cylinder as you are doing this. Once you have bled all four wheel cylinders, top of the master cylinder. You can buy a bleeding apparatus that will let you bleed the master cylinders by yourself but you have to be careful and buy a good one. If bleeding is done correctly, you should not have to pump the brake pedal to get full pressure in the system. Of course, you can only do this once you find the leak and fix that. Beamer

Thanks for the info. I would like to get it to a garage and let the real mechanics fix the problem. I live on the side of a beautiful ridge in TN and it would be very difficult to get a wrecket to my garage. I was hoping that I might be able to add fluid to the master cylinder and get the car out of my garage, to the street safely. I'm not sure that this is possible. Have you had any experience where you could safely add some fluid to the master and and have the brakes work for a short distance??
Thanks.

I have filled many M/cyls that were dry and did not require bleeding. As long as there was nothing disconnected that allowed the fluid to escape when the pedal was pumped bleeding will not be required....but it will take many SLOW pumps of the pedal to get the pedal to come up.

If the pedal does pump up apply very hard pressure to the pedal for about one minute. If the pedal slowly sinks to the floor do not drive the car any distance where brakes are required. If the pedal remains firm you are good to go but use caution.

You still have an ace up your sleeve. If the brakes fail completely, you still have the emergency/park brake, and back compression from the engine, if you leave it in gear.

Have you tried calling a machanic that would come to your house? Here in California some machanics do house calls. They have a shop on wheels. Just a thought...Oscar

Thanks everyone. I'll let you know how this turns out....

Still a mystery!!!! Several days ago, I filled the master cylinder, which had suddenly become completely empty. I pumped the pedal a couple of times and had great breaks. I got the car to the street, trailered it to the garage and the mechanic today tells me that they cannot find a leak anywhere. The brakes seem fine.

Since the brake pedal suddenly just went clear to the floor, I am somewhat afraid of what might happen especially driving on these Tennessee hills, ridges and mountains.

Any suggestions would be most appreciated. Thanks.

Here is a possible. The last time the brakes were worked on the mechanic filled the master cylinder. After many miles of travel the linings were worn and adjustments to each wheel have settled in. It took fluid to make up for the vacated space. Along with evaporation and the normal wear on the brake components you ran out of fluid. Fluid is replaced in the master cylinder and we are back to square 1. In other words, it did not need a leak to use the small amount of fluid needed.

Move to Nebraska. :)

If it was dry, you filled it, and he can find no leaks I would make a habbit of checking the fluid level every month. This is not the first time this has happened.

If it were my car and I had no knowledge as to when the brakes were last rebuilt I would go thru the master and wheel cylinders, replace the three rubber lines, inspect the steel lines, and feel much safer when driving anywhere....and have a working parking brake.

I just purchased the car recently and immediately took it to a garage and ask that they check brakes, etc. I'm not absolutely sure that they, in fact, did this. I don't know when the brakes were last worked on. I can certainly check the fluid level on a monthly basis.

Is it common on old cars to just end up one day with a brake pedal that goes clear to the floor????

Gary,

It definitely is NOT common. Even with a discovered problem, the brakes should pump up a bit with multiple depressions on the pedal.

The "possible" explanation offered a very posts back seems very plausible. Gene's advice is good also. In the meantime, ANY time you take the car out, I would check the fluid level. If all is OK after several of those every time checks, maybe check every-other-time type of thing. I guess you could go along like that.... But ultimately I don't think I'd be really 'comfortable' until a complete brake job was done. By someone I knew and had confidence in. Your statement about not being sure they checked the brakes indicates you have some doubt. Maybe not the place you want to do the brake job????

A good friend of mine, who is a real stickler about brakes, has taught me it doesn't matter if the car will start or not, if you don't know if it will STOP.

Just my thinking....

Bill.

Thanks. Great advise.

Sure nuf Gary. Hope all goes well with your 'new' Forty-One....

This scenario scares He!! out of me. As far as I am concerned brakes do not fail SUDDENLY due to time, adjustments and evaporation of fluid. If the brakes failed there is a problem, if there was fluid in the MC then there would be a problem in valving or piston fit. If the MC is dry and puddles under neath which was stated then there is a leak. Time for a total brake job, I would really not want this car behind me coming down off a beautiful TN ridge.