The best repair method?

[handirifle]

I was loaned a Case 580E backhoe, by a neighbor, with the warning it has some leaks. Well, a big one showed up after about an hour of use. One he thought he fixed. One of the FEL steel lines is leaking where he thought he had brazed the split, but wasn't sure he had got all the spot.

I can braze it, I found where the leak is, but was wondering if brazing will hold up to the hyd pressure?

 

[mjncad]

Can you post a picture of where the problem is?

If it's a split in the line, I doubt it very much. If it's an ORFS (O-Ring Face Seal sleeve on the end of the metal line, then brazing is how they are joined to the metal lines.

Brazing needs CLEAN surfaces that are fluxed properly. You will need to get all the oil out of the line.

 

[doall]

I agree if it is a split it will try to "outrun" your weld and keep moving up. Not to mention the line is probably week in other places too.

 

[Mark @ Everlast]

I've successfully brazed every hydraulic line I have ever tried to do. Its really only a matter of getting it clean. I wonder what kind of flux he used?

You might want to try to burn off the the excess oil of the area first then clean it. You might want to try to tin the area first with the filler, then come back and braze it up.

 

[handirifle]

I may have mispoke. I think it's a rub area, not an actual split. It's on an elbow, when the tubing makes a bend, and not near a fitting. I have brazed steel lines before (I used to do A/C work for a living) but those lines didn't operate at these pressures.

I'll be removing the line today, and will take pics, as I go.

Mark
I have never done what you mentioned, though, about tinning with the filler. Do you mean the brazing rod? Can you expain?

 

[Car Doc]

This probably isnt the "best" way but it worked in a pinch!

I repaired a hydraulic line that had a .22 hole in it with tin and silver solder and a propane torch 15 years ago on my old Massey in order to get it on a trailer where I bought it at and its still 100% leak free.

All I did was clean and sand all surfaces and pre-tinned the tin on the back side and also the line and wrapped the tin around the line and wrapped that tight with mechanics wire and soldered it up with silver solder worked way better than I would have dreamed of and is still holding today.

 

[tommu56]

I'v repaired wear points in straight lines with a sleeve brazed over the thin spot cut tube find another piece of tubing id just over the od of the repair at least the same wall clean all the paint off both pieces clean with alcohol let it dry braze it up.

For splits drill a hole in the tube at the ends of the crack clean paint off clean with alcohol make sure its dry and braze it up.
tom

 

[Mark @ Everlast]

If you need to, after you clean it, you can get the base metal hot enough that the brass filler will "spread out over the surface, without forming a bead. It'll give you a good base to run the bead back over.

 

[handirifle]

OK it's fixed. Fixed it first thing this AM. I took pics and will try to post them later. It was an elbow but within a few inches of a flare nut.

Once I got the line off and had a good look, I saw that it had been globbed on before, and there was small linear crack in the previous braze. I took the glob to the grinder (yes grinder) to be able to make use of the emery cloth to clean it. Once the braze was thinned a bit I cleaned and re-brazed.

Works great.

 

[Mark @ Everlast]

That's great. Brazing is a highly underrated repair process. It has considerable strength, and it can join dissimilar metals. Its not "SOLDERING" as some people believe. But, its a credible process used in both repair and manufacturing. Its also a great choice to repair cast iron when there are no wear resistance issues or major loading concerns. For example its great to repair a crack on the external water jacket on an engine block or it can be used to fix a cast iron leg on a pot belly stove.