Master brake repair

[heyhayes]

Help, brakes are dragging on my 1950 B-2-D, ordered master brake cylinder kit from Rock Auto. I'm a little confused, the repair manual shows a thin washer between Piston and Piston cup. All the repair kits for master cylinders show a rubber washer but no thin metal washer??   I installed the rubber washer in-between the piston cup and piston, was that a no-no?

heyhayes

[NiftyFifty]

Why not buy a new master? I wouldn't consider rebuilding the old worn out ones when new is available and for a fairly reasonable cost.

[heyhayes]

Looks like I'm heading that way....know of a good outlet for master cylinders?

 

[NiftyFifty]

Rock Auto lists them, I see three options when I just looked...likely the best price, just be sure to properly load it before install 

[squirebill]

How did you determine the master cylinder was causing the brakes to drag?  Does the brake pedal tend to stay down rather than return to the full out position when you release it?

[lonejacklarry]

I have never had a master cylinder cause brake drag.  Not to say that it is impossible but I would be looking for a bad rubber brake hose.  A lot of times the inside of the hose will deteriorate and allow the fluid to move one direction but not allow or slow down fluid movement in the other.

[pflaming]

42 minutes ago, lonejacklarry said:

  A lot of times the inside of the hose will deteriorate and allow the fluid to move one direction but not allow or slow down fluid movement in the other

 

The above is great motivation to replace old brake hoses and lines. TKS. I've replaced both hoses and lines. 

[NiftyFifty]

Never a bad idea to replace all the wear parts at once, if your doing the master, change the rubber hoses and all the fluid...it’s all prone to breakdown over time

[squirebill]

Reason I asked was as an 18 year old in the late 60s with a 50 Plymouth as a daily driver I had a situation with a brake pedal not fully returning.  Since I had places to go and things to do, I got in the habit of looping the  toe of my right shoe under the brake pedal and pulling it to the full out position.  Problem solved?!?!  But then my Mom asked me why my shoe was so screwed up.  Explained the situation and immediately my step-Dad and I were completely rebuilding all the wheel cylinders and bleeding them with no change to the pedal return problem.  Got to the point where we were getting ready to pull the master cylinder for rebuild or replace.  This is where we discovered the brake pedal on it's pivot shaft was covered with dry rust dust.  Sprayed the area liberally with penetrating oil/lube and problem was solved.  No need for MC overhaul and probably rebuilding the wheel cylinders was unnecessary.  Slim chance this is your problem but it is worth a check since the Dodge trucks have a similar brake pedal/shaft arrangement.

[heyhayes]

Installed new master from Rockauto, problem solved.  

Thanks for the comments

 

[MBF]

If you added a washer between the cup and piston, you may be preventing the piston from returning to its full rest position.  I'd also check lube the pedal where the shaft goes through it, and make sure the return spring is present and hooked up properly.