Ive read many posts here and on other sites about SS tubes leaking since I was dealing with this issue myself on a brake system where literally every part was brand new except the pedal.
Since I was determined to do this exercise only ONCE more, Here's what I did:
If your engine is in, especially with headers, the first thing I did was pull the steering column for more room.
Inspect all flares for gouges, fins etc. Even brand new flares can have issues. I bought an inexpensive lapping tool and lapped every flare. The tool was $58 and came with 2 sizes of dies which hold the tube securely in the tool. I then moved to installing the 3/16" copper flare seals
( Grainger) after opening all the connections and blowing out the brake fluid.
I started at the P valve which is the most cramped area between frame rail and header. For the larger nut/ bore fittings you will need to center the flare washer! A tube flare can center the washer if it is slightly off center on a horizontal joint, at vertical joints the flare seal falls/rests way off center, and installing the tube/ nut can crush it in place blocking the port. A 3/16" flare seal is the correct seal size, A 5/16" flare seal will center better in these larger bores but the center hole size was too close to the working perimeter of the tube flare and I wasn't willing to gamble. Here's how to center the 3/16" flare seal in the vertical larger tube nut bore:
I snipped cotton swabs in half, use the swab end and solvent to clean the tube flare. Slide your flare seal onto the stick end of the swab as a holder. Minutely dab super glue onto the seal taking care to keep it away from the center hole, immediately push the flare seal onto the the tube flare and spin it to disperse the glue. Hold for 15 seconds or so then holding the flare seal securely rotate the swab stick and remove. Check the center hole for any glue or debris.This flare is ready to install. Remember to tighten loosen, tighten more, loosen etc to work the flare and seal into each other. The tightening feel of the copper seal is very different and far less abrupt than SS by itself. USE TUBING WRENCHES! And work the fitting back and forth.
For the diff breather/ splitter connection, ( you don't need to center the seal with glue, these are the smaller bore inlets) I removed both tubes and un- bolted the splitter from the diff. Invert the splitter so the tube comes at it from below, this way you can simply rest the flare seal on top of the tube flare and install. Rotate the splitter 180 and repeat for the second tube.Do both tubes this way, finger tight so tubes can move/ rotate a bit , now jockey this assembly back into place on the diff. If the flare nuts are too close to the diff housing for a tube wrench: use a longer doner bolt in place of the hollow breather bolt so it doesn't snap off. With a longer doner bolt, lift the T splitter off of the diff housing enough to get a tubing wrench on each nut. Tighten as described earlier, then replace doner bolt with breather bolt, secure and move on to the wheel cylinder connections.
I had to re-glue flare seals a couple of times when they got knocked off or didn't bond. Be patient, make sure you clean the flare and seal thoroughly before re- gluing.
I wasn't excited at all about using any kind of glue on the seals. I had no luck with a dab of grease, but did have silicone as a back up. Short of pulling the engine for room at the P valve, I saw no other option of centering the flares and am happy to report I have 0 leaks. Yesterday I bled the system, with no helper I used the jar of fluid/ tube method and had good pedal in about 40 minutes.
Copper flare seals were 100 % successful. I hope this little summary helps anyone in the future dealing with brake tube leaks.
Since I was determined to do this exercise only ONCE more, Here's what I did:
If your engine is in, especially with headers, the first thing I did was pull the steering column for more room.
Inspect all flares for gouges, fins etc. Even brand new flares can have issues. I bought an inexpensive lapping tool and lapped every flare. The tool was $58 and came with 2 sizes of dies which hold the tube securely in the tool. I then moved to installing the 3/16" copper flare seals
( Grainger) after opening all the connections and blowing out the brake fluid.
I started at the P valve which is the most cramped area between frame rail and header. For the larger nut/ bore fittings you will need to center the flare washer! A tube flare can center the washer if it is slightly off center on a horizontal joint, at vertical joints the flare seal falls/rests way off center, and installing the tube/ nut can crush it in place blocking the port. A 3/16" flare seal is the correct seal size, A 5/16" flare seal will center better in these larger bores but the center hole size was too close to the working perimeter of the tube flare and I wasn't willing to gamble. Here's how to center the 3/16" flare seal in the vertical larger tube nut bore:
I snipped cotton swabs in half, use the swab end and solvent to clean the tube flare. Slide your flare seal onto the stick end of the swab as a holder. Minutely dab super glue onto the seal taking care to keep it away from the center hole, immediately push the flare seal onto the the tube flare and spin it to disperse the glue. Hold for 15 seconds or so then holding the flare seal securely rotate the swab stick and remove. Check the center hole for any glue or debris.This flare is ready to install. Remember to tighten loosen, tighten more, loosen etc to work the flare and seal into each other. The tightening feel of the copper seal is very different and far less abrupt than SS by itself. USE TUBING WRENCHES! And work the fitting back and forth.
For the diff breather/ splitter connection, ( you don't need to center the seal with glue, these are the smaller bore inlets) I removed both tubes and un- bolted the splitter from the diff. Invert the splitter so the tube comes at it from below, this way you can simply rest the flare seal on top of the tube flare and install. Rotate the splitter 180 and repeat for the second tube.Do both tubes this way, finger tight so tubes can move/ rotate a bit , now jockey this assembly back into place on the diff. If the flare nuts are too close to the diff housing for a tube wrench: use a longer doner bolt in place of the hollow breather bolt so it doesn't snap off. With a longer doner bolt, lift the T splitter off of the diff housing enough to get a tubing wrench on each nut. Tighten as described earlier, then replace doner bolt with breather bolt, secure and move on to the wheel cylinder connections.
I had to re-glue flare seals a couple of times when they got knocked off or didn't bond. Be patient, make sure you clean the flare and seal thoroughly before re- gluing.
I wasn't excited at all about using any kind of glue on the seals. I had no luck with a dab of grease, but did have silicone as a back up. Short of pulling the engine for room at the P valve, I saw no other option of centering the flares and am happy to report I have 0 leaks. Yesterday I bled the system, with no helper I used the jar of fluid/ tube method and had good pedal in about 40 minutes.
Copper flare seals were 100 % successful. I hope this little summary helps anyone in the future dealing with brake tube leaks.
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