Help! Brake pedal is stuck at top. Won't depress.

[Bolts]

I was able to buy a 48 Deluxe coupe yesterday and trailered it about 400 miles home. The car had been sitting a long time, but rolls. When I got home, while still on the trailer, I filled the master cylinder and pumped the pedal many times, sometimes hard, other times just pushing lightly. That worked ok and I started to feel some pedal. A little while later the pedal got stuck at the top and acts like there is something jammed in the way so the pedal can't be pushed down.
Has anyone experienced this? The car rolls freely.
Thanks, Tommy.
BTW, I'm stoked having it at home in the garage.

[Shadetree]

Sounds like the check valve is stuck or clogged in the master cylinder, but usually the car won't roll and the pressure has to be bled off. You may have to remove the master cylinder and repair it or replace it.

Congratulations on your purchase. You will enjoy it!

[Bolts]

There might not be any pressure on the brakes, even though I thought I was getting some resistance on the brake pedal. If the check valve is stuck, is it likely that I damaged the master cylinder by trying to loosen the pedal by pushing on it many times?

[sortkaffekop]

Congratulations on your "new" car!

My learned lesson from buying, and revitalizing an old original car that has been standing for years:

DO expect to:

Dismantle and inspect ALL theese things:
Master cylinder
Wheel cylinders
Fuel pump
Vacuum unit
Waterpumps
Distributor
Radiator!!!

Face it, and do it! Or you will have an endless and steep learning curve for the next 6 months!

Christian/Denmark

[Terry,OH]

pumping the master cylinder, with fluid in it, will not damage it. You should do a physical inspection to make sure nothing has physically jammed the pedal. For fluid to reenter the master cylinder the master cylinder piston has to return all the way to it's at rest position. If you remove the cap and operate the pedal, when you release the pedal you should see a stream of fluid returning to the master cylinder. The stream can make a mess so be prepared. If you see a strong stream it is a good indication the master cylinder is making hydraulic pressure and the pressure is being released. Both Good Why was the master cylinder empty? Got a leak or never filled?

[Bolts]

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Terry, there was a good stream as you describe and a squishing sound could be heard under the car at the rear wheels when I pumped the pedal, so I think fluid was moving in the system. The emergency brake handle won't move very far, so could that transfer bar inside the rear hub that works with the emergency brake be jammed somehow preventing the brake pedal operating?
Another novice question: does the master cylinder come off from underneath the car?
It's so cold here now I can't get under the car to inspect anything right now but when it warms up a little I intend to go through the brakes as a first effort.
As I remember from years ago one needed a puller to remove the rear drums, which I may have to buy.
I probably should just go ahead and remove the front seat and floorboard to get a good look at everything anyway.
Tommy
Thanks Christian and Shadetree, it's a beautiful little car and I'm really lovin it!

[DICK SPADARO]

Nice car been setting for a long time.... Not in use master cylinders and wheel cylinders are junk from moisture corrosion !
Just adding fluid and pumping brakes if the reservoir is empty is not bleeding the brakes to make them work. You need to follow the instructions for brake service. If this car has been in storage or setting for a period of time you need to physically check master cylinder and wheel cylinder by removing the hubs and checking for corrosion in the boot cups as well as pulling back the master cylinder boot to check for oxidation. If there is white debris in the boots time to replace.

[Bolts]

Thanks Dick, I agree. Just was trying to use the brakes to help get the car off the trailer. We wound up using a come-a -long and chains. My question is why did the pedal all of a sudden lock up?

[professorpat]

Henry, I am here in Prescott. We restore early fords here in my "hobby" shop. PM me with your contact information and we can help with advice, info, and assistance. Pat OBrien.

[rotorwrench]

DOT 3 fluid can eventually absorb enough water that the wheel cylinders and master cylinder can be ruined with pistons stuck so tight they have to be driven out or hydraulically removed. Microbial growth, jelled fluid, and corrosion oxides fill voids with crud. If a master is empty of fluid, it's a good chance that the stuff leaked out or jelled in the system over a period of years. It would be a miracle to get a system working correctly without disassembly & repair after setting a long period like that.

[V12Bill]

Don't overlook the brake lines either. If you have moisture in the system, water will lie in the low spots and cause rust and eventually will blow out on a panic stop. These lines must be double flared. get a decent double flaring tool and some good line benders to do the job correctly.

[Bolts]

I believe it was Mark Twain that said something like this:
It ain't the things you know, but the things you know that just ain't so.
Or words to that effect.

I had no idea the hydraulic brake system could get so dry and useless.
Anyway, I discovered the folly of trying to "pump up" the brakes in a car that has been out of use for many years. It just ain't gonna work!

My previous experience was with repairing running cars, not restoration.
I thought I knew, but found out I didn't know about old dry brakes and lots of other things too.

Removing the MC and wheel cylinders was a good lesson. Everything was locked up and dry so hard, no amount of pumping could EVER move the shoes! White powder is not brake juice.

The WHOLE system needs to be replaced or cleaned out and repaired to be safe.

Many thanks to all the members who contributed to this thread.

It's humbling to discover your own ignorance. I like to joke about not being as smart as I look, but working on this old wreck, I learn it's actually true.

[Barry-ct]

Be safe and replace everything from MC to wheel cyls, rubber lines, steel lines, shoes. Don't use anything other than maybe the fitting block and bolt at the master cyl. Most everything can still be bought to make it safe.

[PeteVS]

A while ago, there was some discussion about imported wheel cylinders being drilled incorrectly. You might consider having your cylinders resleeved if they're pitted.