Hard brakelines '59

[RockinKees]

Probabably not the right place to ask this here...

Which hard brakeline do you use in your truck?
I mean 3/16 or 1/4 or a combination of the two and why?

Thanks in advance!!

[OrrieG]

Need to be matched to the master cylinder, calipers and/or wheel cylinders you are using. Basically the mc is a holds a quantity of fluid and the piston pushes a specific volume out the ports, thru the lines to the caliper or wheel cylinder. The volume has to match the amount need to move the caliper or wheel cylinder. The line size between them determines the volume of fluid that moves. If the mc piston move more fluid than the caliper or wheel cylinder needs it will have less travel distance, resulting in very touchy brakes. If it does not move enough the mc will bottom out before the caliper or wheel cylinder is fully engaged. If the line size is to small or to large the proper volume of fluid will not be transfered. Pressure is the same through out the system since brake fluid is not compressible. My truck has 74 disc/drum. Stock mc has a smaller reservoir for front disc, larger for rear drums. The front line is smaller (3/16 I believe) and splits into two small lines coming out of the proportioning valve. The calipers need less volume to engage. The back line is larger (1/4 I believe) and goes back to a tee that then splits to the wheel cylinders.

[mr48chev]

I'd have to agree with Orrie. I've always tried to size my brake lines to match the parts I use.

Meaning that If I am using 54 Chevy car front brakes, a 69 Chevy pickup master cylinder and a mid 70's Chevy Nova rear axle I'd use brake lines that matched the front and rear brakes respectively. On my truck with that setup I used 3/16 all around and it worked well.

[RockinKees]

Ok, great!
Thanks guys, never thought of it that way.
I have to copy the Jag brakes then.

I have all the Jag stuff from the same car, except for the brakelines...
Makes it a bit easier, once I found out what they used

[_Ogre]

orrieg pretty well summed it up
3/16 for disc, 1/4 for drum
truk is 4 wheel disc and i used 3/16 all around

[1project2many]

Breaking down what Orrie G. said with a little more detail:

Drum brakes use return springs to pull the shoes away from the drum. So the wheel cylinders are "emptied" each time the brakes are released. To apply the brakes you must refill the cylinder quickly and take up all slack between shoe and drum. Use 1/4" brake line to get as much fluid to the w/cyl as possible in the least time.

Most disc brakes allow the pads to sit extremely close to the rotor or even contact it. There is much less (if any) return built in to pull the pads back. So the brakes are always ready to apply with a minimum amount of fluid. Even though the caliper holds more than the w/cyl, it takes less fluid to apply disc brakes. In this case you can run 3/16" line to the calipers. It would not hurt to use 1/4" line, but it adds to the amount of fluid needed to fill the system.

[_Ogre]

and... most benders are universal type that bend 3 different sizes, they ''work'' but that's about it
usually the bend radius is big and making back to back bends takes a lot of room



if you can swing it; buy a size specific bender, the radius will be tighter and you can work closer to fittings
this helps when your working around the mc, bending around cross members and at the calipers or drums
i was lucky to be able to borrow a couple benders from a friend; 3/16 for brake lines and 3/8 for fuel and trans lines

[OrrieG]

Ditto, line bending tools is one place you do not want to save money, cheap ones will kink the lines, after you replace two or three you have paid for the difference in tool price.

[Russell Ashley]

"Stock mc has a smaller reservoir for front disc, larger for rear drums."

Orrie, I'm surprised that no one picked up on this, but this is backwards. The fluid level stays constant in the drum side so a large quantity of fluid is not needed there, but the fluid level decreases in the disk brake side as the disk brake pads wear, so the larger quantity of fluid is needed to fill the caliper bores as the pads wear.

[RockinKees]

Thanks guys for all the info.

The Jag also has 4-wheel discs, so I go with 3/16 lines.
We have benders, that will give no problems.

[OrrieG]

Originally Posted by Russell Ashley

"Stock mc has a smaller reservoir for front disc, larger for rear drums."

Orrie, I'm surprised that no one picked up on this, but this is backwards. The fluid level stays constant in the drum side so a large quantity of fluid is not needed there, but the fluid level decreases in the disk brake side as the disk brake pads wear, so the larger quantity of fluid is needed to fill the caliper bores as the pads wear.

You are right, I went back and looked at the photo of my install, the lines cross between the mc and prop valve which confused me.

[roger55]

Sorry guys.
Line size makes no difference in the working of the brakes. 3/16" and 1/4" will both work fine and the brakes will work the same either way. Disc or drum, it makes no difference. It wouldn't matter if it were 2" pipe, the brakes would work exactly the same.

The only difference is that there is less friction loss with the larger diameter line. Since the rear is further from the master and both brakes use the same line for most of that distance, 1/4" is usually used in the rear to reduce the friction loss. More friction would just mean a little more pedal pressure from your foot would be required when the brakes are applied but it would not make a difference on pedal travel or anything else.

[_Ogre]

as stated that is incorrect, plumbing a drum/drum with 3/16 line would make for slow squishy brakes
plumbing a disc/disc in 1/4 matters not, other than more cost, work and the amount of reducers you'll need to buy

[roger55]

Originally Posted by _Ogre

as stated that is incorrect, plumbing a drum/drum with 3/16 line would make for slow squishy brakes
plumbing a disc/disc in 1/4 matters not, other than more cost, work and the amount of reducers you'll need to buy

I suggest you do some more research. You will find that I am correct.

Front drum brakes were plumbed with 3/16" line from the factory. But, the rear lines are longer resulting in more pipe friction. 1/4" was run to the rear.

More friction might cause more pedal effort while the brakes are applied but not after the shoes have made contact with the drums. The feel and action after that point would be the same.

[Speedbumpauto]

I don't remember a vehicle from the 60's when drum brakes were the standard that used anything other than 3/16 line. The lines on these trucks were all 3/16 from the factory. Most of the aftermarket MC's are set up for 3/16. You would have to use an adapter to go to 1/4 on the style I use.

[roger55]

Originally Posted by Speedbumpauto

I don't remember a vehicle from the 60's when drum brakes were the standard that used anything other than 3/16 line. The lines on these trucks were all 3/16 from the factory. Most of the aftermarket MC's are set up for 3/16. You would have to use an adapter to go to 1/4 on the style I use.

I've never seen the factory use anything other than 3/16" for front brakes but I've seen 1/4' used on the rear (from the proportion valve to the tee at the rear). From the tee to the rear brakes is always 3/16".

[RockinKees]

The brakelines are 3/16 all around now. Truck is stock with drum/drums.

I go to disc/disc and ordered 3/16 line.
Must be good, I think?

[Speedbumpauto]

That's what I did and I have drums in the rear, although, after my best laid plans, I might change the rear to disc.

[Old Crow]

I replaced all the brake lines on my wife's '54 panel(all stock drum/drum). They were all 3/16" when I started, and they're all 3/16" now.
The truck stops fine.

[thumper56]

Sounds like you are doing your own line fabrication, including flaring. Just a thought to add... the Jaguar brake calipers probably will require British inverted nuts and flaring will be "Bubble/European" flare rather than the double flare used in pre 90's US domestic vehicles.

Same 3/16 line- but different flaring procedure and fitting required.

[RockinKees]

Thanks for the tip Thumper56!

I can make both flares, thats no problem.
I also use Goodridge Stainless hoses up front made for this type of car, the nuts will all be new.