Brake line opinions

[gcorron]

OK, I am aware that this is like pouring gas on a fire to put it out, but I'm going to anyway!!

I have been involved with Volvo 240's for a long time. Still own a 91 240 wagon. A long time ago I was working on brakes and noticed that Volvo uses Cupra/nickel brake lines. They never rot, and are very easy to form and make a perfect double flare pretty easy.

I'm planning on replacing the brake lines on my 97 Cummins. I know they use steel because I've had to replace 2 rotted lines since I have owned it.

I'm either going to use the cupra/nickel, or the stainless lines, but I don't have any desire to bend, or flare, the stainless ones so I'd get an entire pre-bent set from someone. They are a lot more expensive than making them out of the copper lines.

OK, fire away - copper nickel, or stainless?? Suggestions as to who has the best pre-bent stainless?
I am going with the stainless braid for the front brake.

George

 

[BigPapa]

Copper nickel is the way to go.

 

[Topzide]

Second the copper/nickel lines!

 

[DavidC]

Third on copper/nickel

 

[JR]

No question there. Cupronickel lasts as long as SS, MUCH easier to work with and cheaper. My 01 VW still has all of its Cupronickel factory brake lines at 260k miles and 20 years. Thats 20 winters in the rust belt.

 

[Jim W]

Agree on the copper/nickel lines. In fact there is are two SAE standard for brake line materail that you should use. One is SAE J527, and the other is SAE J528 here are the links. The minimum allowable tensile strength for the tubing is 290MPa, yield strength 170MPa Good Luck!
SAE J528 automotive copper tubing specification standard - Knowledge - Yuyao Jiayuan Hydraulic Fitting Factory (jiayuanfitting.com) to the standard.
SAE J527 tubing brake line specification standard - Knowledge - Yuyao Jiayuan Hydraulic Fitting Factory (jiayuanfitting.com)

 

[gcorron]

Thanks everyone for your input! I sort of indicated that I was very likely to go with the copper nickel but wanted to see if anyone had any real good reasons for going the other way.

I was afraid I would start the 'which oil is best' controversy! I've seen that one get completely out of hand over the years here. For the record: Amsoil.

Oh, another fight to start: I've used ONE Red top battery for about 15 years (no, not the same one) but only use the one. Current battery is 9 years old, so I may have to consider a replacement this year!

Thanks again, this site is the best!

George

 

[mwilson]

Copper/nickel here as well. One thing I did not see mentioned was double flaring.

I always double flare any connection be it brake lines, fuel lines for a furnace, etc. Way less chance for a crack to develop in the flare.

 

[DavidC]

And, the best flaring tool is ?

 

[gcorron]

I did say the copper lines made double flaring much easier in the original post.
Of course, anything under more than a tiny bit of pressure gets double flared. I expect, if you didn't double flare a brake line, it wouldn't take much time before you regretted it.
I have 3 sets of flaring tools with the double flare addition. The one I almost always use is a set I got from Snap On a LONG time ago. I think they were made by Blue Point at the time. I don't think it makes a lot of difference.
Again, thanks to all of you!

George

 

[JR]

I am pretty sure double flaring is required whether it is the SAE or DIN type.

 

[mwilson]

I did say the copper lines made double flaring much easier in the original post.
Of course, anything under more than a tiny bit of pressure gets double flared. I expect, if you didn't double flare a brake line, it wouldn't take much time before you regretted it.
I have 3 sets of flaring tools with the double flare addition. The one I almost always use is a set I got from Snap On a LONG time ago. I think they were made by Blue Point at the time. I don't think it makes a lot of difference.
Again, thanks to all of you!

George

By Golly you did...I missed it.....

I've seen many jokers up here just do a single flare on brake lines.....HVAC people never seem to double flare either and then you get little #2 fuel oil / dust bunny gobs on every connection...I sigh deeply and then dig out my double flare set to do it all over.....

 

[Jim W]

SAE standard is 45DEG double flare for brake lines, hydraulic lines and fuel lines have been 37DEG single flare. Ever since I started to deign fluid lines in the 70's. Most of the automotive industry still uses 45DEG flare fittings for brake lines.
But a lot of that has changed in the last 30, years or so to what is called "ORFS" (o- ring face seal) fittings. These fittings will with stand 5000 PSI pressure and will tend to leak less and cannot be over torqued when tightening them as flare fittings can be, spreading the flare!