Brake issue..

[DAYLEY/CHALLENGER]

 Well this is the story,   My brakes have  started acting up., or I should say down.  Press the pedal, brakes work , feel solid and then the pedal goes down some more.  Dash light comes on as the pedal has gone too far, but still  have stopping  ability.  Have breed all 4 wheel cylinders.  Same result.   Had the wife push on the pedal while I had the  cap off of the master cylinder and there is a small squirt of fluid in both chambers like there is air being expelled.  Not low on fluid.  Any suggestions.    Oh...1970 Challenger.  All drum brakes.

[Chryco Psycho]

usually a bad seal inside the master causes the pedal to drop once the brakes are applied

[1 Wild R/T]

usually a bad seal inside the master causes the pedal to drop once the brakes are applied

Yup, new master cylinder time...

[Racer57]

Yup. What they said.

[ChallengerHK]

 

[DAYLEY/CHALLENGER]

Thanks guys..........by the way I  typed  the original post on the Ipad and I did not BREED the 4 wheel cylinders....but I did bleed  them.   

[BIGSHCLUNK]

When I first read this post description it just sounded like typical ol' MOPAR drum brakes... good first pump, roll the dice on the second.   

[1 Wild R/T]

When I first read this post description it just sounded like typical ol' MOPAR drum brakes... good first pump, roll the dice on the second. 

My experience back in the 70's with Mopar drums was they work OK around town & at lower speeds, once your hitting 60+ you had one stop... 80+ you better have allot of room cause you aren't stopping... Kinda like a ship, you need room to slow down or your gonna go through whatever gets in your way...

[dutch]

80+ you better have allot of room cause you aren't stopping... Kinda like a ship, you need room to slow down or your gonna go through whatever gets in your way...

does make you feel alive once you`ve dodged everything in your path... 

[DAYLEY/CHALLENGER]

Next bit of information.........I have looked as several sites and the  master cylinders they show have all sorts of different ways to secure the top.  Mine has the wire holding the top in place. Anyone have what they know is an original to their car and can supply a pic......Thanks in advance.  By the way......1970......Drum all way around and 11" drums at that with power assist.  Pic attached of mine.....

[tman]

Hmmm, I could be wrong, but it looks like your master is for a disc/drum setup.

[1 Wild R/T]

Yup disc M/C...  You need one with equal sized front/rear reservoirs ....  Or better yet add disc brakes...   Couple options.....

[Racer57]

Next bit of information.........I have looked as several sites and the  master cylinders they show have all sorts of different ways to secure the top.  Mine has the wire holding the top in place. Anyone have what they know is an original to their car and can supply a pic......Thanks in advance.  By the way......1970......Drum all way around and 11" drums at that with power assist.  Pic attached of mine.....

You have the same setup that I have, except I have front disk brakes with drum rear. The booster is a Midland Ross for 71-74.

[tman]

Next bit of information.........I have looked as several sites and the  master cylinders they show have all sorts of different ways to secure the top.  Mine has the wire holding the top in place. Anyone have what they know is an original to their car and can supply a pic......Thanks in advance.  By the way......1970......Drum all way around and 11" drums at that with power assist.  Pic attached of mine.....

You can get the right m/c at any parts store.  I tend to like Raybestos or Wagner.  Also I like new vs reman, but any of them will work.  I tend to find that the new ones last much longer.  Rockauto or even Amazon has new Raybestos mc36221 for around $30 new not reman.  All kinds of options out there.

http://images.brakepartsinc.com/images/1/14E4C/2341C-MC36221-7_150.jpg

[wantone]

I've got front discs' and rear drums... i have that same MC.   You're definitely going to want the double hump one.