Thread tape on brake lines?
 

Do you use thread tape on brake lines? I haven't noticed any from the factory when I broke the seals, nor seen any reference to any in any of the DIY's, but thought I'd ask before I tighten everything down and start filling the system with new fluid.

brakes or clutch, bleeders don't need any tape or loctite....since they were installed on cars.
Any "loctite" fluid is forbidden about contamination of same fluid in.

I'm talking about where the hard lines connect to the soft lines. I'm replacing the soft rubber lines with braided lines.

there's no need as long as you order the correct lines and tighten it correctly.

OK. Thanks.

Is there any harm in using it?

Thanks.

I have had no leaks at all ever since I changed my lines about a year ago. you don't need the tape. just make sure you have the proper wrench to tighten the lines since it makes it so much easier.

Actually Yes.

Sealant is not required as the seal occurs inside the fitting and is metal on metal.
Any 'goo' on the threads risks getting some inside the fitting and the line.
This could cause brake fluid contamination and cause brake fade or failure.

Used very sparingly, one can use the teflon paste as a anti-seize, but only up high on the threads. Like loctite 565
I only do dry fittings on dry fittings.

Use at little as possible if you do, as those fittings are relatively soft. You really don't need it though.

[ame="https://www.youtube.com/watch?v=n0PJTRKr0RU"]Brake Plumbing Basics with Speedway Motors - YouTube[/ame]

Plumbing is where thread tape is used. It is a lubricant used for tapered pipe threads only. It will 100% leak on anything that wasn't going to seal by itself anyway. If you are using say a straight thread for a temp sensor then a sealant like Loctite 567 can be used.

Thread tape especially if applied by inexperienced people can clog valves, ports and all sorts of stuff. In Hydraulics you'd be amazed how many times we have to repair things that were broken because some idiot used thread tape. It lubricates to allow tapered threads to tighten easily. It doesn't seal jack all.

KISS

If it dont belong there dont put it there. Like dielectric grease on coil packs. It came without it and it worked fine. Why add it?

Nobody asked why you're considering this. Why are you considering this?

Sorry, I cant help myself.
You are telling him the right thing (dont use thread sealant on brake fittings)
But for the wrong reason (teflon tape cant seal threads).

In fact teflon tape does seal threads, it is used on almost all threaded pneumatic fittings because of the sealing characteristics.

The real reason one does not need thread sealant on brake fittings is that by the time the working fluid were to get to the threads it has already leaked past the seal.
The seal is the metal brake line smashing up against the fitting mating surface.
The threads ONLY purpose is to apply massive force to press the two mating surfaces together.

AN and flare fittings are also this class of fittings.

In fact, on rigid brake lines, if the fluid leaks past the primary seal (the crushed tip of the tube), it wont even try to leak out the threads, it will come up the middle of the fitting along the tube and out the top of the fitting.