Hydraulic brakes questions - super hard pedal

[Charlie Stephens]

Originally Posted by billybronco1

Here is a pic of the front & rear outside view of the backing plates - I hope to pull all the wheels next week - what do these look like to you original off something else - maybe a kit ??

The backing plates are 1946-48 Ford since there is no adjustment at the bottom (or top in the case of the rear where the backing plates are mounted upside down). Most antique Ford parts suppliers (and many local auto parts houses) will have all parts for these. Go for the made in USA parts. This is probably the most common conversion and you should not have any problems using them if everything else is ok.

Do you have and know how to use a hub puller for the rear wheels? With brute force and the wrong puller you can destroy an axle easily.

Charlie Stephens

[columbiA]

The 42-48 front brakes have stepped wheel cyls with 1" & 1-3/8" bores.The rear stepped cyls are 1" & 1-1/8" bores.Large end of cyls always face the front.If the LR backing plate is turned upside down,you need to use the cyl from RH & vice-versa or you end up with small end of cyls facing forward.Also,your M/C is too small-you need the 39/48 M/C which is 1-1/16" bore instead of the 13/16" one that you have.

[fordcragar]

Out of curiosity, where would you guys buy brake parts? New cylinders or kits?

[John Kuhnast]

Looks like 1939 to 1941 to me. I have these on mine and thay work fine. Suggest useing a dual master.Early mustang works well.Make sure to get the one that is for shoes on all four weels.Google 1939 ford brake adjustment as they have an unusal system of brake adjustment.

[steve s]

Originally Posted by Charlie Stephens

The backing plates are 1946-48 Ford since there is no adjustment at the bottom (or top in the case of the rear where the backing plates are mounted upside down). ...
Charlie Stephens

Originally Posted by John Kuhnast

Looks like 1939 to 1941 to me. I have these on mine and thay work fine. Suggest useing a dual master.Early mustang works well.Make sure to get the one that is for shoes on all four weels.Google 1939 ford brake adjustment as they have an unusal system of brake adjustment.

I agree with Charlie: 46-48.

One more heads up: Depending on how cobbled together your setup is, you might not have all 46-48 wheel cylinders. I found three different kinds in mine.

Steve

[Walt Dupont--Me.]

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My guess is the master cyl. is to big. As someone said, use a early Mustang dual cyl made for drum drum brake. I set one of mine up one time with jouce brakes and used a master from some truck, had full pedle as hard as a rock but didn't stop good. I installed a smaller master, the pedle felt normal and stopped mormal. Walt

[Bob Johnson]

The master cylinder you have is a 13/16" bore which is quite small. The way hydraulic brakes work is smaller bore master cylinders require LESS pressure to activate the brakes but require MORE pedal movement. It is like being on the long side of a teeter-totter. A larger bore will require MORE pressure to activate the brakes. But require less pedal movement.

Since you have a small bore master cylinder. I would guess that the problem is elsewhere. The possibilities are clogged brake lines, frozen or bad wheel cylinders, fouled or bad brake linings, ...

Bob

[billybronco1]

Okay I guess I wont know till I pull it apart but I'm getting mixed reviews here on the master cylinder - one says too big and one says to small. I'm going to ping the previous owner and see if he can shed any light on if it was always like this - not sure I get the answer I want to here.

And to answer the below question - the answer is no

"Do you have and know how to use a hub puller for the rear wheels? With brute force and the wrong puller you can destroy an axle easily."

[fordcragar]

Originally Posted by Bob Johnson

The master cylinder you have is a 13/16" bore which is quite small. The way hydraulic brakes work is smaller bore master cylinders require LESS pressure to activate the brakes but require MORE pedal movement. It is like being on the long side of a teeter-totter. A larger bore will require MORE pressure to activate the brakes. But require less pedal movement.

Since you have a small bore master cylinder. I would guess that the problem is elsewhere. The possibilities are clogged brake lines, frozen or bad wheel cylinders, fouled or bad brake linings, ...

Bob

Originally Posted by billybronco1

Okay I guess I wont know till I pull it apart but I'm getting mixed reviews here on the master cylinder - one says too big and one says to small. I'm going to ping the previous owner and see if he can shed any light on if it was always like this - not sure I get the answer I want to here...................................

What Bob was saying is that with the smaller master cylinder, it would apply more pressure than a larger one; which gives you the idea that the problem is not in the master cylinder.

The brakes that were installed on your car would have used a 1 1/16" diameter master cylinder stock. The master cylinder that is installed, because it is smaller, would give you more pressure.

[Dodge]

Maybe someone put Viagra in the brake fluid........

[charlesea]

Billy, these drums appear to be the 39thru48 Ford like the ones on my car. The backing plates appear to be the same per the adjustment for the shoes.
No one has mentioned that you might have air in the lines. You need a helper to bleed all 4 lines. One to pump & hold while the other lets the air/fluid out of each wheel cylinder. You can catch the fluid so as not to cause a mess. I think air in the lines might cause a hard pedal. Google 39-48 brakes & look at those parts for a comparison. Thompson Garage is a good place to look also. My brakes work great & they are the 39-48 style. Good luck

[van Dyck]

39 to 41 Ford brakes versus 42 to 48 Ford brakes
-adjustable anchors -floating anchors
-smaller wheel cylinders -larger wheel cylinders
-plain backing plates -six rectangle dimples
near the perimeter
-brake shoe round anchor holes -elongated anchor
holes
The brakes in question here are 42 to 48.
The first year for Mustang tandem master cylinders is 1967 - made mandatory in the automotive industry. Use the 1967 - 68 MC designed for the 4 drum system - they use a residual pressure check valve for both front and rear. It works.
Do not mix DOT 3 (glycerine based) with silicone brake fluid.

[Kirby1374]

Originally Posted by charlesea

Billy, these drums appear to be the 39thru48 Ford like the ones on my car. The backing plates appear to be the same per the adjustment for the shoes.
No one has mentioned that you might have air in the lines. You need a helper to bleed all 4 lines. One to pump & hold while the other lets the air/fluid out of each wheel cylinder. You can catch the fluid so as not to cause a mess. I think air in the lines might cause a hard pedal. Google 39-48 brakes & look at those parts for a comparison. Thompson Garage is a good place to look also. My brakes work great & they are the 39-48 style. Good luck

Air would make it soft

[1931 flamingo]

Ck the plunger arm in the M/Cyl, it should NOT be tight against the piston when retracted. There should be some clearance so fluid can return to the reservoir.
Paul in CT

[billybronco1]

The peddle is up to the top and does not depress a 1/2" and is super hard - I found the brake reservoir today under the seat - it had two reservoirs and one is empty so something is wrong there. I ask why two different reservoirs, is one for the front and the other for the rear? Tell me more about removing the rear drums - thanks

[Charlie Stephens]

Originally Posted by billybronco1

The peddle is up to the top and does not depress a 1/2" and is super hard - I found the brake reservoir today under the seat - it had two C and one is empty so something is wrong there. I ask why two different reservoirs, is one for the front and the other for the rear? Tell me more about removing the rear drums - thanks

You should fill up the empty reservoir and see what happens. I have never encountered anything like you describe before. Are these both high pressure reservoirs? Does the line from the master cylinder go to both of the reservoir that in turn feed the front and rear brakes separately? You might contact Wilwood about the way their systems work.

A good description of using the hub puller can be found at
http://www.mindspring.com/~bozarth/id5.html

If the hubs were not tightened properly almost any puller can be used. If they were tightened properly (about 200 foot pounds but look it up since everyone disagrees on this number) the cheap pullers will not do the job and may damage parts. There are a couple of pullers out there that are almost as good and I am sure someone will post them. Try contacting local Model A clubs and see if they have one to loan (or maybe rent if you are not a member of the cub).

Charlie Stephens

[billybronco1]

Has anyone ever used one of these hub pullers for drums

[Charlie Stephens]

These guys rent the KR Wilson puller:

Mac VanPelt
VANPELT SALES LLC
Cincinnati, Ohio USA
www.vanpeltsales.com

Charlie Stephens

[billybronco1]

Pretty far from MA

[Charlie Stephens]

Originally Posted by billybronco1

Pretty far from MA

Try calling local old Ford Parts stores or inquire about shipping.

Charlie Stephens