Can you braze a hydraulic line?

[NormL]

One of the metal hydraulic lines for my dozer split. My neighbor happened to stop by while I was taking it off and he said that he could weld it with a coat hanger. He used a gas acetylene torch and the metal coat hanger, and it's held perfectly for over a decade now.

Welding with coat hangers works great but stay away from the paint coated kind. That creates an ash that interferes with the bonding of the weld. Use only the varnished hangers. That seems to act as a flux. Just my 2 cents!!

 

[59 Sons]

OK. So I dremeled off the epoxy and sanded back down to clean steel. I think my description of the leak might have been misleading. I wouldn't call it a split as I have seen tubing split at the annealing line. It might be more of a crack, or even just an impurity point that got stretched around the outside of a bend. It would seep fluid during normal operation and only squirt when a function reaches termination.

 

[59 Sons]

So I blasted out the line with nitrogen, knowing full well that I was not going to get all of it out because the tube has a deep belly in it. I was nervous about using a solvent, because I wasn't certain I could get the solvent out of the tube and that seemed more problematic than leaving some oil in there. I inserted my nitrogen several inches into the end of the tube and left it purging while I heated the pipe to displace any oxygen and also help to keep the pipe from getting too hot. There was a plastic collar on the compression fitting just a few inches away from the repair and I didn't want that to melt. I put a generous amount of paste flux all over the repair area, started heating the flux until it went chocolate, and started dabbing flux cored high silver rod on the area. The flux was bringing out all kind of impurities. Ugly! Once I had the whole area wet with high silver and flux I started dabbing the 15% rod on top to build up a fat patch.

 

[59 Sons]

Regarding the issue of overheating the steel tube, my silver rod melts well below 1500° so the tube never even got to dull Cherry. It just barely got shiny.

 

[59 Sons]

It's ugly as sin, but it appears to be holding. It got dark on me so I will know better in the morning when I can test more tractor functions.

 

[etpm]

It's ugly as sin, but it appears to be holding. It got dark on me so I will know better in the morning when I can test more tractor functions.

Well, if it doesn't hold you can still braze a big patch over that. But it will probably hold. It certainly looks thick enough.
Eric

 

[ovrszd]

A Craftsman at work. Great pics and tutorial. Someone, someday will stumble onto this thread in their search of repairing a steel line and gain knowledge. Thanks for the follow ups and pics!!!

 

[Smokeydog]

Thank you for the write up and hope the repair is permanent. Good details.

Had a small crack on a power steering line on a B20. Would have required much dismantling and time to repair. 6010 Stick welded as a temporary fix to get back going. Lasted 25 years till I sold it. In my case more luck than skill.

 

[59 Sons]

Okay, I cleaned off some of the flux and did a full warm up on the tractor and tested the highest pressure functions. Everything looks good. No seepage at all. I like that you can see how the flux cleaned the pipe and floated all the impurities to the top of the silver. I guess it's time to put the deck back together. I think I will hold on to the tube Kubota sold me in case I need to have a flexible hose fabricated on to its ends in the future. Thank you everyone for the moral support.

 

[metalbender]

You got your PHD in brazing. Looks good. Is it an injury risk if it fails?