Brake Master Cylinder Valves

-
Dodge74

Dodge74

Well-Known Member
Joined
Aug 14, 2010
Messages
387
Reaction score
17
Location
sunny FL
I have a brake master cylinder off of a '74 Dodge Dart Sport, diameter 15/16. I would like to use this with my disc brake front conversion. The conversion is off of a '74 Duster. I was told I could use this master cylinder but that I needed to take off a valve. Does anyone know what valve, where it's at, and how I take it off? Or does anyone have a recommendation for a master cylinder I can use?

:violent1:
 
They are talking about a "residual valve". I have never seen one, but understand it is inside the ports where the tubes exit and that you can pull them out easy with needle-nose pliers. I don't know if they were still used in 1974. The later wheel cylinder kits with the cups on the ends of the springs are supposed to eliminate the need for them. I understand you can buy an external residual valve aftermarket, but why?

I expect you know that you will need a proportioning valve to run rear drums with front disks. You can get an adjustable one for ~$25. If you won't have a power booster, you might want to read up whether a 15/16" MC is OK with disks. You might need a smaller bore. On my 65 Dart, I put a booster and MC from a ~96 Breeze on 74 Dart stand-off brackets. No front disks yet, but I wanted to plan for that someday.
 
Usually you can remove the brass seat by screwing the proper size sheet metal screw into the hole in the seat, and prying it out with a claw hammer just like a nail.


30j2vwo.jpg
 
Thanks 67Dart273 for the great picture. I was wrong, it takes more than needle-nose pliers. That brings up a good point. If your 1974 MC looks like the picture, with a larger reservoir aft (for front brakes), it is already for a front disk brake car, so won't have a residual valve on the fronts (as in picture). If for a drum-drum car, the 2 reservoirs will be the same size. That is how us clever FABO guys can see just a photo of an engine bay and say "nice that you have disk brakes".
 
Why would you remove the residual valve from the rear drum brake portion if the car still has rear drum brakes?

I can see removing it from the reservoir that serves the front brakes if you are trying to use a drum/drum m/c on a car that will have disk/drum.

...or you can buy a new/reman m/c that is for a factory manual disk/drum car at rockauto for $50.


We need to know-

A are you planning for power or manual brakes?
B are you planning on keeping the rear drums? (rear disks are a whole different ball game)
C did the m/c you are asking about using come from a car with manual or power disk/drum or drum/drum brakes?


...and if you can, get the valve from the car you got the m/c from, if it is a disk brake car.

many Mopars after 1972-ish used the "Texas" shaped valve that includes the prop valve.
I believe these are all the same and can be had cheap at most salvage yards.
Look on M bodies, and even trucks up into the 90's.
The only potential issue is plumbing, as it will likely want the lines to be in different places than what was on your car originally.
 
My MC looks just like that one but a little different... The reservoir has equal sides were the fluid go's. Can i still use this one or do u guys know of one i can use.... Let me know what u guys think. THANKS..........
 
Thank you for your time YY1.Yes i plan on keeping rear drum set up with front disk. I want to keep it manual brakes.This MC came form a Drum/Drum set up. I was told maybe a MC from a 87-88 MC out of a truck may work. let me know what u think....

Thanks.....
 
You have an MC from a drum-drum car. Remove the residual valve from the tube that will go to your front brakes (usually the aft one). Re-read the posts above, because that should have been clear.
 
just use the right parts we are talking about brakes here
 
You must log in or register to reply here.
-

Back
Top