brake line size

[Jmageee902004]

So im in the process of running new brake lines throughout my truck 1964 4x4 because all the bleeder screws on the wheel cylinders where stuck and the flex lines needed to be replaced. I've decided to run 1/4 inch steel lines to 1/4 wheel cylinders and I dont have power brakes.

I'm having a hard time finding 1/4inch flex lines,the lines that go from the steel lines to the wheel cylinders. The originals where 3/7 and 24", Most Local stores only have 12" 1/4 flex lines and say they dont have 1/4 lines that are 24" or don't know how to find them in the system. Is their another vehicle that has 24" lines 1/4 that i can have them look up, or a place to order them online.

My second question, the guys at NAPA told me that i have to run a small size 3/8 line from the T off the 1/4 master cylinder or the brakes don't work. Is this true? they kept showing me pictures of power brakes and said they figured its the same for non power brakes, so i'm not sure if i need to switch from a bigger to smaller line or not.

Im running 1/4 lines because i had a bunch of extra steel line to use.

[OrrieG]

Were the stock line 1/4"? I know the line size has to do with the amount of fluid required for the MC and wheel cylinders to work correctly. I had to get special lines for my truck and used Russell directly. Their telephone customer support told me what information I need to get, then got me exactly what I needed for my frankentruck. I got stainless braided lines.

[Jmageee902004]

Im not sure what the whole system was i just pulled it thinking converting to 1/4 inch would be a pretty easy install considering everything would be new. I know from the master cylinder it was 1/4 because my new line bolted in.

[Kim57]

Most guys running new lines are using 3/16. that's what I used on my project.
You may check with a 4x4 truck store as they will probably have flex lines in longer configurations for the raised vehicles.
Kim

[mknittle]

More volume could be asking for problems. i would use 3/16" it' cheap aside from stainless.

[bajabob]

I am using 3/16 on project. Not sure about the bigger line. 6-7 bucks a 6foot section with fittings at most parts houses.....

[dwcsr]

The line size for drum brakes is 1/4". 3/16 for disc power or not.

If its front disc and rear drum then run 3/16 front and 1/4 back.

The difference in power , non power on the older trucks is piston size in the master and wheel

[bajabob]

Dwcsr
Then I have a question for you. What if you have drums all around but are using an aftermarket hydroboost in stead of the original single master cylinder???

[dwcsr]

Drums are 1/4" lines. Doesn't matter how your powering the system. I would make sure they are new cylinders and not the cheap Asian ones. Hydro is going to almost double your line and cylinder pressure.

[Jmageee902004]

Mine are drums all the way around I will check the local 4x4 shop here in town to see if i can get longer 1/4. Ive got the brakes all plumed except for the flex lines, so i might as well buy the lines and see if it works or not. Could i just run 3/6 from the T that runs to the brake cylinders and 1/4 the rest of the truck or would that cause some kind of pressure issues?

[bajabob]

This was a good question as I just finished plumbing the rear lines in 3/16 steel lines. I made a quick call to CPP (where I brought the frame mounted hydro booster). According to their tech, either size will work 3/16 or 1/4.
Not sure I would mix size of lines, but have no data to back that, just my opinion.