master cylinder replace

[ironman3452]

hi all, i have a new dual master cylinder, to install in my 64 panel, it has the old lines, and i will be removing them to put new ones in, my question is what goes where, old master cylinder has only one line, new one has two, what i need
to know is what port goes to the rear brakes, so i can buy new lines, and install them, so let me know, thanks.

[Steeveedee]

Do you still have all drum brakes? What does the dual master cylinder fit, originally?

[mongocanfly]

lots of older vehicles were single reservoir....blow a wheel cylinder or brake line and you loose all your brakes...along came safety which led to a dual reservoir m/c..if you loose front or rear brakes it leaves you with some stopping ability...usually the front reservoir is for the front brakes and the back for the back....I would recommend using the new dual m/c and replumbing your brakes..

[Steeveedee]

That's why I'm asking. I'm not making any assumptions about anything until I know what the master was originally intended for. I see it all the time where someone works on the brakes and just puts a master cylinder without regard for what would have been designed in from the factory.

[Rickysnickers]

I'll try go answer the original question. Generally, the front portion of the master cylinder is for the front brakes and the rear for the rear brakes. Depending on what you have and the plans for the future, I'd suggest getting an adjustable proportioning valve from Wilwood. It will work with drum or disc brakes. This is the one I'm referring to, http://www.wilwood.com/MasterCylinde...emno=260-13190

[Steeveedee]

No one knows what master cylinder he has. Until that happens, any recommendations are pretty pointless. It isn't our money, so we can throw all kinds of his at the question? To the OP- if you don't really know what you have, I'd recommend finding a friendly local knowledgeable brake mechanic to help you through this issue. Brakes are the most important of any system on a vehicle, for obvious reasons.

[Rickysnickers]

He said he has a new dual master cylinder. I was merely saying what lines supply fluid to the brakes.

[68C15]

CPP has some real nice kits. Instructions are a bit shady at times but the parts are good.

[Liteman504]

I think you should check the bore size of the new master cylinder and make sure it is the same diameter as the singe line master cylinder you are removing. Also , the new master cylinder has to be for an application that uses drum brakes on front and rear if that is what your truck has

[Steeveedee]

Originally Posted by Rickysnickers

He said he has a new dual master cylinder. I was merely saying what lines supply fluid to the brakes.

OK, sorry if I seemed to come on too strong to that. But we don't know what master he has, so it might go either way. I've seen people putting Corvette disc brake master cylinders on full drum brake cars, simply because it was for a Corvette and there was some perceived benefit.

[mongocanfly]

hheeeeckkk....if that master cyl came off a vett it probably added 20hp....

[Rickysnickers]

Originally Posted by Steeveedee

OK, sorry if I seemed to come on too strong to that. But we don't know what master he has, so it might go either way. I've seen people putting Corvette disc brake master cylinders on full drum brake cars, simply because it was for a Corvette and there was some perceived benefit.

No offense taken

[Popcorn W]

ChiefRocka did an excellent write up on this subject several years ago.
It may help the OP pick out a new master too since the correct one is cheap.
http://67-72chevytrucks.com/vboard/s...d.php?t=332148