I once did so on a Saturday to keep a front end loader going till Monday. Has to be clean from oil or it won't take and I used 30% silver with flux. It held. It wasn't a fracture, it was pin holing. I was back Monday morning with a replacement tube because I had no faith in it.

 

Yes. I have had very good results with brazing hydraulic steel pipes. You need to take the pipe off. and clean
it well from oil or rust. Ordinary flux coated brazing rods works well. I like the bare rods with a can of flux powder
to dip them in. I have always used Oxy Act with a fine nozzle. Get the pipe just red hot and the flux and filler will
flow over the crack or leak.

 

Just replace hydraulic cylinder

Dave

 

And how would that fix a leak on a hydraulic tube? With that being said, flux coated brazing rod will work fine. If you have a tube bending outfit locally they are very reasonable priced to make a new one.

 

O/A welding works but brazing will too. The big thing with brazing(not silver solder) is you have to build it up 3 or 4times thicker that the steel line so it will hold the pressure. Former neighbor was an awesome welder and brazed a line on my track loader. I said I think it needs more build up but he said the crack is closed. Blew out the 1st time I used it and I replaced it with a hose. I didn't have O/A cylinders at the time.

 

I did an elbow on a baler gate cylinder. Full of oil, and still on the baler. Kept hitting it until it quit leaking 6013. I still remember that evening. Kept having to put little fires out when the oil lit, and dripped on the ground.

It held, but it was not optimal.

Tubing???????? Naw, I wouldn't even try it on a bet. Too thin.

If you're in trouble, go to the ag place, and pick up some hydraulic hose, and some adapters. Plumb it with that, and walk away. Will probably last the lifetime of the equipment.

 

If you haven't pinpointed the leak.............raise the arms, and see where it's leaking. Take gravity into account, and trace upwards. There has to be a source for the oil. You'll very soon find the culprit. Might even be a lousy reconnection ya did. I've done the same. Use Teflon tape to seal NPT joints.

Or, watch the lines during application of pressure. This might tell you where it's coming from.

I have a pinhole leak on a line that goes to the oil cooler for the low pressure hydraulic system. It sprays oil out the side in a fine mist. K'kins spotted the source the third time it covered her with a film of oil when she walked alongside the tractor when we were moving some heavy stuff with the loader(low pressure line supplies the steering cylinder). I love that woman. AND I MEAN IT. Y'all tell me if your wife would put up with oil mist for any time at all. She's golden.

 

I've brazed hard lines on a cultivator and they've lasted for decades. That being said, not all of them were that successful and the hydraulic oil you lose will pay for new replacements pretty quick.

 

I’ve brazed hydraulic tubing runs on heavy equipment with excellent results. In my instance they were permanent repairs on 3000 psi lines. I used oxy-acytelene and standard flux coated brazing rod. I recall that I did some with the white flux rods and others with the blue flux rod. Both were successful.

 

Got it off this what it looks like .
I bought a schedule 40 with gas coating , but I wonder with the bends if the coating will flake off and cause problems.
Please stop me if you see any issues with doing this repair

 

Most piping for gas service isn’t coated inside to prevent contamination. Brazing is a good way to repair those steel lines. Flux coated rod with some extra flux for good measure. Start heating to burn the oil out. Wire brush and start brazing

 

What ever you do NEVER EVER use your hands to look for leaks. Use a piece of cardboard or paper as the oil could penetrate your skin. I'd replace as much of the rusted part as possible on both lines and wouldn't any brazing or welding at all (unless space limitations). Do them far enough apart they aren't side by side. A good hydraulic shop can re-flare them and make a proper new section of correct hyd. tubing to bolt right in. Hose could also be used. I had an impossible to remove without having to remove the hyd. tank on my Cat track loader. A steel line that went to the backhoe quick connects had rubbed through because a clamp was missing. It had some very tight bends off the control valve to clear all the other lines. I cut it off where it went straight along the hyd. tank and straight where it went to the quick coupler. Had the steel parts flared and used 2 pieces of compact hose to connect them. This was about a 4' steel line that was snaked in at assembly. Could spray a lot of oil if it failed and JIC flare fittings are very popular on hydraulics. Forget brazing or welding and fix it so it will last. Hyd. tube is strong and not too thick. That rust is just a leak to start sooner rather than later. Not a time for quick ******* fix.

 

There is also the "Ermeto" compression adaptor for tubing, they come in all sorts of threads on the non tubing side. Those things bite into the tubing when you tighten the compression nut like you wouldn't believe. I've used them to adapt tubing to hose on 5,000 PSI hydrostatic systems. With appropriate hose of course. Those have been my go to for repairs under cabs on all sorts of Cat, Deere, and Case equipment. Install adaptor and attach hose. Done.

 

I have brazed hydraulic tubing many times, without fail. Most have been on equipment where vibration from something rubbing on the steel line rubbed it through. Zip ties and corrugated sleeve for wiring are frequent culprits, as is the thinning on the outside of sharp bends. If there is a thin spot from rubbing I will cut the thinnest steel out with my pocketknife first. New lines are hours, if not days, away when downtime is big money. I can be back running before you even get to the dealership.

Rotted through is a special case. You need to clean the entire area. You won't get all the rust out of the bottom of the pits. Then basically you build a new tube out of braze metal over the top of the original tube.

 

Doesn't sound like a production machine and I am looking at redoing all the lines on my 4 in 1 bucket. Hyd. shop said flaring would be a lot cheaper than compression fittings. They have really good turn around time and the most knowledgeable people! Most important the best price by far. Changed seals on my 4 in 1 bucket cylinders (rods removed), $93/ea. for seal kits and an hour labor each to remove and install. Rods looked good and they agreed. Polishing would have cost more but seals were likely original from 86 and get a lot of dirt sitting on the wiper seals which causes the weeping.

http://stirlinghydraulic.com/

 

Not sure of the brand, but the guy I buy from, has compression fittings for high pressure tube-to-tube applications.

I can salvage the flared connectors at the ends of my problem tubing, then simply use the compression fittings to attach the new tubing I'll bend to fit.

It's not so much that I can't have the ends flared to match OEM, it's the time it's going to take to make the trips to Tulsa to get it done. The "fix" has to be rerouted, so you're looking at buying the tubing, bringing it home, bending it to fit its new home, then going back to have it flared.

Of course, it's gonna take days to make the new die, and shaft, assembly for the bender to fit 1/2.................but that's sort of my style:laugh::laugh::laugh:

 

I finished using brazed in pipe for repair . The braze flowed nicely I think . I’m not that good of a brazer but it appears to be sealed .
I spent a lot of time trying to find hose and fittings with one thing after another not making sense . I found the this pipe fit over the tubing . I heated the pipe and bent it to match cut out bad section . Brazed it after I slipped the pipe over tubing .

This new part the dealer wanted $1500 .
A shop wanted 500 to bend new tubes .
I couldn’t afford either option , I had to try this repair myself
I got the pipe from the hardware store for $8+a new 5/8 drill $25 to ream out weld seam to slip pipe over the tube .

I think it will work okay .

 

I don't see why it wouldn't work. If it wet out, which it looks like it did, leaks shouldn't be any problem.

 

You didn't use regular cast iron plumbing pipe on a high pressure hydraulic line here, did you? If so, it is way under rated for those pressures and could be a major hazard. You need steel tubing not cast iron pipe. If I didn't understand what you wrote, my apologies, but it sure sounded like you used plumbing pipe the way you described it.

 

Cast Iron pipe????

 

Cast Iron pipe? First thing that went through my head to. Lol

 

The original line rotted out from rust. My experience is that it's usually caused by something holding moisture against it... dirt, mud, general crud. You'll need to keep that area cleaner in the future. My preference would have been the compression fittings and hydraulic lines as well (they don't rust, but they will deteriorate in time)... you can still do that if this fix doesn't work out. I've seen common black pipe (it isn't cast) and plumber's fittings worked into lots of shortline farm equipment... it's not an issue.

 

You should build the brazing up more and not just enough to be leak free. The brass does not have the same pressure rating as steel pipe. Silver solder could be done like you have it but brass should be built up like a fillet weld. Cast iron pipe that small??? It wouldn't bend for one thing. Cast iron was used for sewer pipe and lead was used for joining but not so much anymore. If it was the regular pipe used for water lines it may not have enough pressure rating. Did it have a seam? Hyd. tube is seamless 1010 steel which is very high grade. Seamless pipe can be also be used. It's always best to know what material you're using instead of just using what's laying around.