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I'm stuck and need brake help

I'm stuck and need brake help

FiNorman

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Location
Orlando, FL
Vehicle(s)
1985 CJ7, AMC 360, lunati cam, AX15, Affordable Fuel Injection, edelbrock performer manifold, 21 gallon fuel tank, Old Man Emu 2.5 inch lift, 1 inch body lift, tie rod flip, HMMWV H1 steering box, rear disc brake conversion, Dana 44 rear, YJ to CJ tub conversion, still working on 33 inch tires, Metallic dark blue paint.

Scrambler Project, cosmetically taking it back to the 80's- 1984 Scrambler, Laredo. 258cc, Holley Sniper EFI, 30in tires on Laredo polished wheels, Dana 44 rear, OME 2.5 YJ springs/lift, HMMWV steering box

Previously owned cj 7, 1979, Renegade, 258 and a '89 wrangler
I've run all of my fuel and brake lines. the problem I have encountered is I thought all of the lines were like the fuel line 5/16 diameter tubing, which appears to take a 1/2 male flare.
when I get to my proportioning valve the inputs there are actually made for a 1/4 line and 9/16ths coupler, and 3/16ths line and 3/8 coupler.
Am I ok to have brake lines that are bigger in diameter? at the end of the day it's a closed system that will generate the same pressures correct?
Also does anyone know where I can get adapters to fit the 5/16th line and couplers to reduce into fittings made to fit 3/16 and 1/4 line?
thanks in advance
 
I've run all of my fuel and brake lines. the problem I have encountered is I thought all of the lines were like the fuel line 5/16 diameter tubing, which appears to take a 1/2 male flare.
when I get to my proportioning valve the inputs there are actually made for a 1/4 line and 9/16ths coupler, and 3/16ths line and 3/8 coupler.
Am I ok to have brake lines that are bigger in diameter? at the end of the day it's a closed system that will generate the same pressures correct?
Also does anyone know where I can get adapters to fit the 5/16th line and couplers to reduce into fittings made to fit 3/16 and 1/4 line?
thanks in advance

:)Without getting to deeply into your brake system.......like Master cylinder bore size, Power assisted Disc or drum brakes & sizes at these corners....... Larger lines require more fluid volume which can lead to a harder pedal to push. 3/16" and 1/4" brake lines are the norm.
Basic rule in hydraulics .......small bore,less volume and more pressure versus large bore, more volume less pressure.

:D:D:D:D
 
:)Without getting to deeply into your brake system.......like Master cylinder bore size, Power assisted Disc or drum brakes & sizes at these corners....... Larger lines require more fluid volume which can lead to a harder pedal to push. 3/16" and 1/4" brake lines are the norm.
Basic rule in hydraulics .......small bore,less volume and more pressure versus large bore, more volume less pressure.

:D:D:D:D
So just to confirm the two front brake line should be 3/16ths, the rear should be 1/4, as well as the two hard lines that go to each rear brake from the middle brake extension?

I have a rear disk brake conversion, and will be using a power booster.
 
So just to confirm the two front brake line should be 3/16ths, the rear should be 1/4, as well as the two hard lines that go to each rear brake from the middle brake extension?

I have a rear disk brake conversion, and will be using a power booster.

:)To do this correctly.......the complete system , MC bore size and caliper bore sizes and even length of tubing runs and sizes need to be known...........was the booster just added and was the Master Cylinder purchased with the booster? Disc brakes require more fluid volume and normally a Power MC has a larger bore than a non-power system.......and 3/16" and 1/4" as you noted above should be correct............Brake systems are built and not just thrown together.

:D:D:D:D
 
:)To do this correctly.......the complete system , MC bore size and caliper bore sizes and even length of tubing runs and sizes need to be known...........was the booster just added and was the Master Cylinder purchased with the booster? Disc brakes require more fluid volume and normally a Power MC has a larger bore than a non-power system.......and 3/16" and 1/4" as you noted above should be correct............Brake systems are built and not just thrown together.

:D:D:D:D
the length of the tubing is as follows:
Brake line .
1/4".....103" total length with pieces... 51"+51"= prop to rear crossmember
3/16....38".... total length with pieces 30"+8"=prop to left tire
3/16......-76" total length with pieces .....72"+8" prop to rt tire

the disc brakes come from a chevy s10 rear calipers and rotors....

I was going to reuse the proportioning valve from the 1985 CJ7 .

The master cylinder I was going to use was one that came coincidentally with the tub I bought for my project, a 1995 yj.

I haven't gotten a chance to do much in depth research into the subject, so I'm not really even certain that all of these components can be used together successfully.

If you have any suggestions or recommendations I would really appreciate them.

I will go tomorrow and exchange the 5/16th tubing for the 3/16 and the 1/4 in the appropriate places.

thanks in advance:chug:
 
the length of the tubing is as follows:
Brake line .
1/4".....103" total length with pieces... 51"+51"= prop to rear crossmember
3/16....38".... total length with pieces 30"+8"=prop to left tire
3/16......-76" total length with pieces .....72"+8" prop to rt tire

the disc brakes come from a chevy s10 rear calipers and rotors....

I was going to reuse the proportioning valve from the 1985 CJ7 .

The master cylinder I was going to use was one that came coincidentally with the tub I bought for my project, a 1995 yj.

I haven't gotten a chance to do much in depth research into the subject, so I'm not really even certain that all of these components can be used together successfully.

If you have any suggestions or recommendations I would really appreciate them.

I will go tomorrow and exchange the 5/16th tubing for the 3/16 and the 1/4 in the appropriate places.

thanks in advance:chug:

:)There is a lot of good information on Brake systems both on this site and the internet.......due to all the variables mentioned above , you should first educate yourself to what you have and then proceed to build your own system based on that equipment. This link has a wealth of information on Brakes: Pirate4x4.Com - The largest off roading and 4x4 website in the world.
but should only be considered as reference.........We all like to help folks out with there projects but the difference between a good brake system and one that's not does have consequences........talk to people that are in the brake business that will help you build your system correctly. Thanks!

:D:D:D:D
 

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