Before I seal up the rear floor pan section to the firewall this weekend I want to repair the driver's side heater cable tube that was damaged during the removal of the old firewall. It appears the DACO got a little enthusiastic with the angle grinder in attempting to get the old firewall off and sliced a couple of notches in the end of the cable tube. It would probably still work, but to be safe I'd like to replace a six inch or more section of it as it exits the tunnel and goes through the firewall.

How have people done this? I thought I saw a thread of someone using 5/16" brake tube. Could this be welded or do I have to braze it? I guess I probably need to gently shape/bend it as well, so any advice there is appreciated too.

I think I'm going to have to do something similar with my engine compartment lid release cable tube as well, so I might as well learn to do it right.

Back in the day they were brazed in.

I used thick wall (refrigeration) tubing to recreate the e-brake tubes.
76-914 suggested annealing the old stuff I had that cracked while bending. But the heater tubes are pretty small, you can just about tie them in a knot if need be.
Brake line tubing might be better. But it will be tougher to bend.

I think a fresh tank of MAPP gas will work, but it will take a while.

So you'd recommend brazing it again? I need to pick up some brazing materials then.

Thanks Cary. Continuing to learn a ton from your thread(s)!

Oops ........... brain was going too fast.

I don't think I would trust my self to try and MIG weld them in. Too much chance of blowing a hole into the tube.

It could probably be done. But that's wayyyy over my paygrade. My neighbor in Montana was a Master Welder, if it could be done he could do it. I watched him weld aluminum pipe with my 90 amp Craftsmen MIG.

The tubing I used to make a few sets was McMaster #89955K24
4130 .313 OD , .049 wall thickness. $20.26 for 6 feet.

or send me $15 and I will send you back a set already flared, welded with the correct cross over. All you have to do is install them and make the bends at the exit of the firewall.

Yes - you can mig these if you stuff a piece of copper wire inside the tubing.

Jeff

Doesn't get any better than that.

Love the copper wire technique. Thanks for passing on your years of experience.

Jeff, that's awesome. Thanks for the offer. I'll send you a PM.

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