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Discussion Starter #1
I got the brake system buttoned up yesterday (all new lines from the new MC out), and bled well enough to have braking capacity - nothing I'd want to drive it on, but enough for moving it around the property. I'll do a finish bleed on it in a few days.

Everything was tight (amazing!) except for one joint I've had trouble with before. When I did the front disc conversion about two years ago, the distribution block connection to the right front had a small seepage leak I never could quite get rid of. I thought I had putzed up the tubing flare.

This time, everything old got torn out and I did very careful flares on all the modified lines. The fronts are repro, factory-made ones.

And the damn connection still leaks! I kept everything spotlessly clean, of course, and cleaned and inspected the distribution block before reassembling everything. I've reduced the leak incrementally by tightening the connection, but it still seeps a little (enough to run down the line after four or five hard pedal pushes).

It's to the point where I'm afraid to tighten it any more. What is the torque limit for this type of connection? I'm ass/u/ming now that there's a flaw in the distribution block. Is there anything I can do about this? Is there any kind of sealant I can use on the threads? I know the threads aren't what forms the seal - it's the tubing flare against the brass nipple, which is where I suspect the flaw is.

Besides not wanting to replace the distribution block (it's the original, and they're kind of expensive and hard to find), I don't really want to open up the brake system again! OTOH, I'd rather do it before the engine goes back in...

Any tips, ideas, etc. appreciated...
 

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I had the same problem with the line coming out of the front of the dist. block after replacing all the original lines with stainless ones. I kept tightening it to the point that I was sure it would strip, but it finally held. Recently, I removed all the lines to paint the engine bay, but left that one hooked up. I've got my fingers crossed that it doesn't leak when I bleed the system.
 

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I would not put any type of thread sealant on a brake fitting... The pressure within the braking system can be quite high, and as you already know it is the brass nipple/flare that are supposed to form the seal.

Since you state that you inspected the distribution block, I "ass/u/me" that you saw no visible flaws in the brass nipple... Also, you state that you got all the parts "spotlessly clean", so I will rule out dirty threads and foreign objects. I know of no torque specifications for these fittings, and in the past have sworn that I was about to rip the distribution block off the fender well when trying to eliminate a slight leak such as you describe. Every time I had one of these problems and swore I could not tighten the fitting any more, somehow I was able to turn the fitting just a little bit more and stop the leak.

This is not to say that it is impossible to break something, but look at it this way: If you break the fitting or the distribution block by trying to tighten the fitting when the problem really was an imperfection in the distribution block, you needed a new distribution block anyway... And as you state, it will only get more difficult to fix this if you wait until your engine compartment is full.

Good luck!
 

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Discussion Starter #4
This is not to say that it is impossible to break something, but look at it this way: If you break the fitting or the distribution block by trying to tighten the fitting when the problem really was an imperfection in the distribution block, you needed a new distribution block anyway...
"If it sticks, force it. If it breaks, it needed replacing anyway." :)

I'll give it another twist of the... no, not wrist, but shoulder and upper body. I'll also look for a replacement block in the next week as a permanent fix. Thanks.
 

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had the same problem
put stainless lines on, thought i had it tight,several times,
you can really crank down hard on it before it strips on you.
if it does you can pick up a brass t fitting at a well stocked western auto or other hardware store...smaller phyical size but does the same thing for you for about 3 bucks.
 
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