65 Barracuda Power Brake Master

[TomAce82]

Ok, I have a 65 barracuda with power drum brakes.

I’m replacing a master cylinder that is leaking into the brake booster.

When I pulled the master back off of the booster, I noticed the screw and tear shaped washer that are holding the “guts” into the mc (in my photo) was not there.

Ive also seen gaskets between the master and booster that have a cut out for the screw and washer to sit, like mine, and some just have a small circle in the center of the gasket.


Main question is, was my master cylinder installed incorrectly and is causing my leak?
Q
Thank you!

 

[chewy]

That screw and tear drop washer come off so you can then bench bleed the master cylinder.

Then on mine (manual) there is a 2-bolt retainer that holds the rubber dust boot in place on that, which uses that hole with the screw in it and the opposite hole. My new master came with the boot.

Others can chime in if power brakes are the same, but I suspect it is.

 

[TomAce82]

Power brakes looks like this with an adjustable push rod that comes out of the booster.


The question remains…are the
tear drop and flat head screw removed prior to install against booster? I found one pic on partsgeek and one on classic industries.

 

[chewy]

You have to remove it to bench bleed the master cylinder, and it stays off to install the boot.

 

[TomAce82]

Nothing holding the piston in to the master when i
Removed it from the booster. Is it supposed to have something in either of the threaded holes abound or below the mc piston?

 

[chewy]

The technical service manual offers clues as to how to put it together without it falling out when trying to install it with the brake booster in the car. .

 

[TomAce82]

Yes, I read that in my manual too. Leads me to believe that the screw and retainer are removed. Thank you.

 

[toolmanmike]

Power brakes looks like this with an adjustable push rod that comes out of the booster.


The question remains…are the
tear drop and flat head screw removed prior to install against booster? I found one pic on partsgeek and one on classic industries.

View attachment 1716200690

View attachment 1716200691

The screw and tab hold the piston in the housing. Yes it needs to stay on there and I would bet there is a void in the booster so the raised stop is not an issue. If I remember correctly different designs use a recessed snap ring to hold the guts in the housing so that it can be bolted flat to a bracket or firewall.

 

[chewy]

This diagram shows how the manual master was setup on my 65.

I reused the stop in the picture on the 67 master I installed. I guess the screw and retainer are if you don't have that?