Rear Brake Flex Line

[Shootnride]

David,

Over the years I have encountered quite a few different combinations of brake line fittings and usually when a straight thread fitting was used, it had a flat copper gasket/washer that seated between the flat on the hex portion of the hose fitting and a flat on what ever fitting it was screwed into when tightened. I have only used the copper seat flares on male flare fittings, not on the inverted flare fittings (that doesn't mean that it won't work, I've just never had a need to do it). The copper seat flare that is shown sitting in the inverted flare of your hose fitting (your last photo) looks a little large for the application, but I suppose it may work as long as there isn't any interference with the internal threads.

Sometimes brake line fittings can be a pain in the butt. Hope it all works out well.

Ted

[davids2toys]

Very interesting Ted...I wonder if what I am looking at down inside the tee fitting is a actually a gasket and not the brass surface I thought I was looking at. I will have to check it out when I get back from vacation. Edit. I looked and it is not a gasket. I also have determine it is definitely sloped down towards the center. Therefore it would be sealing to the outside bevel on the hose male fitting
I think the gasket looks bigger than it really is, and the hole in the center is tiny. To me it looks like it will form to the outside bevel at that is it. Besides, even if it did touch the threads I would not think it would matter because the threads are not doing any of the sealing? That is also one of the reasons why you don't put any sealing compounds or tape on the threads because mating surfaces are supposed to be doing all the sealing.
The reason I was thinking of putting it on the other end also is so the metal brake-line flare would not deform the inverted flare like the original I took off the car that I am replacing.
Dave

[Shootnride]

Dave,

You are absolutely correct in that none of the sealing in brake fittings is done with the threads. When I commented about the copper seat gasket interfering with the threads, my concern was that if it was a little too large, it could be tilted out of alignment with the flare before the fitting was tightened. You mentioned that the flare on your old brake line was deformed. That is generally a sign of over-tightening. Many brake system leaks are caused by over tightening of the fittings. The flare on the hose or steel brake line will deform very slightly to form a good seal, but that deformation should be almost imperceptible. I have found that it is best to tighten flare fittings the least amount possible to accomplish a leak free connection and tighten in very small increments as needed. Once a flare has been over tightened, it's usually ruined. Those little copper flare gaskets will help to accomplish a good seal with minimal tightening.

Ted