Seeking brake line installation advice


#1

Hi,
I recently replaced the front left brake line on my 1987 Nova. I’m afraid of a potential problem, however. The new brake line had compression nuts with different lengths. I didn’t want to leave the brake system open and felt the need to get it done before quitting working on it, so I decided to put the short nut into the fitting to the rubber hose going to the wheel caliper, while therefore putting the long one into the three way distribution block under the hood. I was thinking that with the short one in the wheel well, the dirt and grime would be somewhat blocked from getting on the threads because there would be a shorter gap between the hex head of the compression nut and the top part of the coupling to the rubber hose.

I began to doubt my decision when tightening the nuts. I’m afraid that the nut will bottom out (there won’t be any further threads left) and I won’t be able to tighten it enough to compress the flared end of the brake line enough to get a reliable, leak-free connection. It wasn’t leaking, but I might want to tighten it a bit more in the future. I still have to replace the right side and could benefit from member advice.


#2

It should be fine. The hose coupling is not that deep. The longer nut is for where there are issues tightening it with obstructions (like at a wheel cylinder) or for deeper seats like you might find on a distribution block or M/C. Normally, you can tell when the flare seats due to increased resistance. Over tightening is not good. If it’s not leaking, leave it be.


#3

"The new brake line had compression nuts with different lengths. " This is a minor issue, but don’t use the term “compression fittings or nuts” with brake line stuff…They are “Flair Nuts” or “Flair Fittings” Compression fittings should never be used in a brake system…

I agree with Turbo. As long as the fitting tightened properly and you did not “run out of threads” it should be fine…


#4

It occurred to me that maybe nut, itself, is the wrong description, and screw might be a better description since the threads are on the outside. Something like a hollow screw, since the line passes through it lengthwise.


#5

Are you talking about a banjo bolt?

http://www.oreillyauto.com/site/c/detail/BHH0/H94492/N0273.oap?ck=Search_N0273_-1_-1&pt=N0273&ppt=C0142


#6

Caddyman had it right, it’s a flare nut. The term “compression nut” made me look twice to be sure you were describing the nuts on a pre-formed line and not a compression fitting…


#7

That banjo bolt was what I was trying to differentiate away from in my description. That reminds me of the nut and bolt that a bicycle brake cable passes through to hold it tight, and I had actually thought of that earlier, too.

Flare nut does sound familiar now. However, techincally, nuts have threads on the inside and bolts and screws have them on the outside, IMO.

Well, the main thing is that the notion about not really tightening the lines much more than needed to not leak is something to keep in mind. I appreciate the thoughts on the matter.