brake line woes

I've done brake lines before, but not many, and not in a long time. I
have one particular in-line coupling that I can't get to stop leaking.
Other joints appear to be OK, though they could yet surprise me.

I've re-done this one several times. Currently, I have new line (with
manufactured flare) going into the coupling. AFAICT, it's properly
aligned - I could screw the nut in with my fingers. I started off with
only moderate torque, and then tightened further as it kept leaking.

Any thoughts on this would be appreciated.

BTW: why does brake line come with two different nuts (long and short)?

Thanks,
G

George wrote:
> I've done brake lines before, but not many, and not in a long time. I
> have one particular in-line coupling that I can't get to stop leaking.
> Other joints appear to be OK, though they could yet surprise me.
>
> I've re-done this one several times. Currently, I have new line (with
> manufactured flare) going into the coupling. AFAICT, it's properly
> aligned - I could screw the nut in with my fingers. I started off with
> only moderate torque, and then tightened further as it kept leaking.

Sounds like a bad flare or a defective seat in the coupler. Could also
be a chunk of crud in there.

>
> Any thoughts on this would be appreciated.
>
> BTW: why does brake line come with two different nuts (long and short)?

Depends on the application. On some vehicles you need the longer nuts to
thread into a deep fitting. On others it is to allow you to get to the
hex due to obstructions.

>
> Thanks,
> G


--
Steve W.

"George" wrote:

> I've done brake lines before, but not many, and not in a long time. I
> have one particular in-line coupling that I can't get to stop leaking.
> Other joints appear to be OK, though they could yet surprise me.
>
> I've re-done this one several times. Currently, I have new line (with
> manufactured flare) going into the coupling. AFAICT, it's properly
> aligned - I could screw the nut in with my fingers. I started off with
> only moderate torque, and then tightened further as it kept leaking.

We usually just loosen-tighten-loosen-tighten-loosen-tighten 5 or 6 times,
allowing the two parts of the fitting to "smoosh" closer to the same shape.
Kinda the same idea as "lapping" valves. Works with copper and
aluminum washered fittings too. Without exerting any extra force, you
should notice the wrenches turn a little more each time, at least for the
first few cycles.

Universal brake lines.

You can always purchase a short end, or long end for that matter and
just flare it onto the line.
>
> BTW: why does brake line come with two different nuts (long and short)?
>
> Thanks,
> G

On Fri, 07 Aug 2009 13:17:58 -0400, "Steve W." >
wrote:

>George wrote:
>> I've done brake lines before, but not many, and not in a long time. I
>> have one particular in-line coupling that I can't get to stop leaking.
>> Other joints appear to be OK, though they could yet surprise me.
>>
>> I've re-done this one several times. Currently, I have new line (with
>> manufactured flare) going into the coupling. AFAICT, it's properly
>> aligned - I could screw the nut in with my fingers. I started off with
>> only moderate torque, and then tightened further as it kept leaking.
>
>Sounds like a bad flare or a defective seat in the coupler. Could also
>be a chunk of crud in there.

I suppose so - it has to be something. I guess I was hoping for some
kind of magic, "all you've got to do is ..." In the end, I just applied
a little more torque than I was comfortable with, and the leaking
appears to be stopped. At least for now.

G