Power Brakes not working

1 Wild R/T

Well-Known Member
Local time
2:35 PM
Joined
Jul 9, 2019
Messages
7,796
Reaction score
20,147
Location
California
Ok thanks ill try that who's sells original boosters can you still get them
That's a matter of tracking down an original core & sending it out to be rebuilt... Many of us use Booster Dewey... Good news is they were used on B & C body cars, the pushrod on C bodies is different but it can be swapped out with the correct one... It might be worth contacting Booster Dewey & see if he has any cores..
 

Data Plate

Well-Known Member
Local time
5:35 PM
Joined
Mar 23, 2021
Messages
277
Reaction score
29
Location
New York
A guy that has a shop here said it could be the pedal throw angle that power brake cars have a different mounting point for the rod. I never thought it would be this difficult just to put in a master and power booster
 

Kern Dog

Life is full of turns. Build your car to handle.
FBBO Gold Member
Local time
2:35 PM
Joined
Apr 13, 2012
Messages
30,446
Reaction score
99,979
Location
Granite Bay CA
The brake pedal is the same, power or manual. The manual pedal attaches to a pushrod that directly pushes the master cylinder. The power setup uses this reduction linkage and the pedal attaches to this:
PST booster (2).jpg
 

68 Sport Satellite

Well-Known Member
Local time
2:35 PM
Joined
Feb 10, 2010
Messages
1,971
Reaction score
978
Location
San Jose, CA
View attachment 1421124

CARDONE Reman

Power Brake Booster - 50-3501

Part Number: 50-3501

Product Condition: Remanufactured
  • Dodge Charger 1970-67, Coronet 1970-67
  • Plymouth Belvedere 1970-67, GTX 1970-67, Road Runner 1970-68, Satellite 1970-67
That's a single diaphragm drum-drum booster. Have you used this with success? I have the aftermarket dual diaphragm gold one shown above. It works, but pedal feel is terrible.
 

1 Wild R/T

Well-Known Member
Local time
2:35 PM
Joined
Jul 9, 2019
Messages
7,796
Reaction score
20,147
Location
California
View attachment 1421124

CARDONE Reman

Power Brake Booster - 50-3501

Part Number: 50-3501

Product Condition: Remanufactured
  • Dodge Charger 1970-67, Coronet 1970-67
  • Plymouth Belvedere 1970-67, GTX 1970-67, Road Runner 1970-68, Satellite 1970-67
Thats the Midland Ross booster... It's for Drum brakes, doesn't provide enough pressure/assist for disc brakes.. As others have pointed out & I hadn't picked up on this is a drum brake car, so yeah, the Midland Ross unit should be fine...
 

1 Wild R/T

Well-Known Member
Local time
2:35 PM
Joined
Jul 9, 2019
Messages
7,796
Reaction score
20,147
Location
California
So after a little searching it appears the Midland Ross unit probably isn't available either...
 

1STMP

Well-Known Member
Local time
3:35 PM
Joined
Feb 22, 2021
Messages
1,835
Reaction score
3,332
Location
Roswell, New Mexico
The OP said he has drum brakes all around (no disc). That affects MC size requirements.
What designates
requirements are the bore size of the
master, the residual check valves
installed, and stroke length of the
booster pin. I run a dual diaphram
on a 4 disc custom setup. I also run
2lb residual check valves in both
front and rear circuits along with
an adjustable proportioning valve
for the rear circuit. The bore size
of the master is 1-1/8.
The truck stops on the proverbial
dime.
Pedal arm ratio also plays a big part
when switching from drum/drum
to disc/drum or disc/disc.
(edit)
Whether you choose a single or dual diaphragm booster depends on how much brake assist your vehicle needs. A dual diaphragm offers the most assist, and is ideal on an all-disc system or a disc-drum combination. If you want to keep your vehicle’s four-wheel drum system, then a single diaphragm booster would be ideal. In this instance, too much of a brake assist would make your brakes too touchy and send you lurching forward every time you engage the brakes.
20211227_151541_HDR.jpg
 
Last edited:

1STMP

Well-Known Member
Local time
3:35 PM
Joined
Feb 22, 2021
Messages
1,835
Reaction score
3,332
Location
Roswell, New Mexico
That's a single diaphragm drum-drum booster. Have you used this with success? I have the aftermarket dual diaphragm gold one shown above. It works, but pedal feel is terrible.
Dual diaphram boosters are more
suited towards a four disc system.
 

1 Wild R/T

Well-Known Member
Local time
2:35 PM
Joined
Jul 9, 2019
Messages
7,796
Reaction score
20,147
Location
California
Dual diaphram boosters are more
suited towards a four disc system.
Which is why they supplied a 1.125 M/C to increase the amount of assist needed... And if the booster worked that might be okay.... Not really the best way to do it but it should work.... If the booster were doing what it's supposed to...

And a larger single diaphragm booster can be just as effective as a dual diaphragm booster... But the dual takes less space radially and trades that for being deeper...
 

1STMP

Well-Known Member
Local time
3:35 PM
Joined
Feb 22, 2021
Messages
1,835
Reaction score
3,332
Location
Roswell, New Mexico
Which is why they supplied a 1.125 M/C to increase the amount of assist needed... And if the booster worked that might be okay.... Not really the best way to do it but it should work.... If the booster were doing what it's supposed to...

And a larger single diaphragm booster can be just as effective as a dual diaphragm booster... But the dual takes less space radially and trades that for being deeper...
Agreed. Just about all aftermarket
booster "kits" that are sold cater
to the conversion crowd. Those
wanting to upgrade from a drum/drum
system.
My build was under the diameter of
the available space parameters, plus
it being a 4 disc setup.
My advice to the OP would be to
contact CARDONE. There can't be
too many rebuilders that supply these
to Cardone's retail vendors, or as
some else suggested, send his out
to get rebuilt.
We still don't know if the booster is
the pinpointed problem with his
braking woes, and wether or not
he's just throwing parts at it, hoping
the problem is fixed.
Been guilty of this myself.
In a previous post I recommended
he check for vacuum leaks anywhere
else in the system, as vacuum leaks
there will diminish the amount of
vacuum available to the booster.
Thanks for your input in trying to help
an FBBO member.
Always considered you and
RichardCranium to be some of
the most on the wild side.
 
Last edited:

1 Wild R/T

Well-Known Member
Local time
2:35 PM
Joined
Jul 9, 2019
Messages
7,796
Reaction score
20,147
Location
California
Agreed. Just about all aftermarket
booster "kits" that are sold cater
to the conversion crowd. Those
wanting to upgrade from a drum/drum
system.
My build was under the diameter of
the available space parameters, plus
it being a 4 disc setup.
My advice to the OP would be to
contact CARDONE. There can't be
too many rebuilders that supply these
to Cardone's retail vendors, or as
some else suggested, send his out
to get rebuilt.
We still don't know if the booster is
the pinpointed problem with his
braking woes, and wether or not
he's just throwing parts at it, hoping
the problem is fixed.
Been guilty of this myself.
In a previous post I recommended
he check for vacuum leaks anywhere
else in the system, as vacuum leaks
there will diminish the amount of
vacuum available to the booster.
Thanks for your input in trying to help
an FBBO member.
Always considered you and
RichardCranium to be some of
the most on wild side.
We're all just throwing ideas out there.. Without getting dirty all we can do is offer suggestions Luckily (or unluckily depending on your position) we've seen this often enough to know most of the problem areas... And aftermarket parts have been a huge contributor in the last ten years... Was a time failed out of the box was a rare occurrence, not anymore...

Never really thought of myself as overly wild, I like to joke around & I've had lots of fun through the years but mostly I see myself as a technical guy.... With a fairly diverse background...
 

1 Wild R/T

Well-Known Member
Local time
2:35 PM
Joined
Jul 9, 2019
Messages
7,796
Reaction score
20,147
Location
California
From what I've read, my post was a compliment. Nothin' wrong with a
sense of humor.
Oh, I took it that way & do appreciate it... But hardly think my humor is anywhere near R/C's level...
 

Data Plate

Well-Known Member
Local time
5:35 PM
Joined
Mar 23, 2021
Messages
277
Reaction score
29
Location
New York
Im thinking now my master cylinder is wrong they sold me like some have mentioned its to large
 

lewtot184

Well-Known Member
Local time
5:35 PM
Joined
Aug 21, 2011
Messages
4,869
Reaction score
3,165
Location
indianapolis
i have a '69 coronet r/t with the original drums and using a midland-ross booster. what i have found is the lining material on the shoes means far more to stopping than the booster. i've tried all kinds of lining materials and the newer stuff works the worse. with the right lining material my car stops great with no fade. my problem is how do you pick the correct lining? i'm sure there's somebody that's tech savvy on this, but i'm not. there's one thing absolutely for sure and it's that i'd never take those 11" drums off after the rotten experience i've had with after market disc conversions.
 
Top