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Re-flaring Brake Lines

  • Thread starter Thread starter 70mstang
  • Start date Start date Feb 6, 2018

70mstang

Member
Jan 30, 2017
40
7
18
Feb 6, 2018
#1
  • Feb 6, 2018
  • #1
hey guys, working on the car again, does anyone know what size the stock brake lines are on the '70 mustang? I rented a brake flaring kit from the local auto parts store but the sizes seem off. If I put the line in the space for a 3/16 line, the line is too big, I could try clamping it down, but I'm afraid I'd smash it. put it in the space for the 1/4 line and the line is too small, it still wiggles around when I clamp it down. Any helpful advice would be appreciated.
 

tos

Founding Member
Apr 27, 2001
896
68
59
Cincinnati Ohio
Feb 9, 2018
#2
  • Feb 9, 2018
  • #2
Should be 3/16. Your clamp should fit tight enough to grip the line so it wont move when you go to flare it. A cheapo flaring kit will not hold good.
 

Rusty67

20+ Year Stangneter
Dec 3, 2002
3,749
37
109
LA, CA
Feb 27, 2018
#3
  • Feb 27, 2018
  • #3
Most likely the problem is that the line flaring tool you got from the auto parts store is a total piece of trash made of the finest Chinesium money can buy. I've used a few of those piece of crap and they don't work well enough to flare anything beyond super mild steel. If the lines on your car are original they might just have too much actual iron in them for those junk tools. You can take the line off and take it to a good shop that can flare it for you or you can try to find a place that will rent you a good flaring tool. Or you can buy a good one like the mastercool kit. I think it is about 300 bucks for that kit?
 

70mstang

Member
Jan 30, 2017
40
7
18
Mar 2, 2018
#4
  • Mar 2, 2018
  • #4
I came to the same conclusion you did, wound up bending new lines anyway though, just because the old ones have been re-flared too many times, too short to save I'm afraid.
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Mar 23, 2018
#5
  • Mar 23, 2018
  • #5
I gave up flaring years ago when the brake lines they were selling were made of crap and would split every time you tried to flare them. Not sure how they are now. The new black coated lines look to be of better quality so they may be OK. But for the last 30 years I've been just using standard over the counter pre-made lengths.
 
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