brazing a hydraulic line

[etpm]

If this were my tractor and if I had the limited experience you do I would either remove the line completely and take it to a welder or if I had to repair in place I would first try silver bearing plumbing solder. Silver bearing plumbing solder can have a tensile strength of 15,000 PSI. See this link: https://www.stoodyind.com/Catalogs/FISC/current/05catpg372.pdf
If a tin/silver alloy is used to flow over the joint and later it is decided to braze the joint the tin/silver alloy can be cleaned off and the joint brazed. Any miniscule amount of the tin/silver solder left on or in the joint will not interfere with brazing. Tin/lead solder however must be avoided at all costs. Lead will contaminate the joint even if you think all the lead is removed. Tin/antimony solder must also be avoided. Only tin/silver alloy can be used. It is also possible, with proper torch technique, to build up quite a thick solder bead. This can also be done with brazing but it is harder. Anyway, just my 2 cents.

 

[etpm]

I forgot to say that of course the plumbing solder melts at a much lower temperature, hence my posting about this option.
Eric

 

[coloradotrout]

If this were my tractor and if I had the limited experience you do I would either remove the line completely and take it to a welder or if I had to repair in place I would first try silver bearing plumbing solder. Silver bearing plumbing solder can have a tensile strength of 15,000 PSI. See this link: https://www.stoodyind.com/Catalogs/FISC/current/05catpg372.pdf
If a tin/silver alloy is used to flow over the joint and later it is decided to braze the joint the tin/silver alloy can be cleaned off and the joint brazed. Any miniscule amount of the tin/silver solder left on or in the joint will not interfere with brazing. Tin/lead solder however must be avoided at all costs. Lead will contaminate the joint even if you think all the lead is removed. Tin/antimony solder must also be avoided. Only tin/silver alloy can be used. It is also possible, with proper torch technique, to build up quite a thick solder bead. This can also be done with brazing but it is harder. Anyway, just my 2 cents.

Excellent points. It's a small leak so just layering on a bit may hold. JB weld slowed it down for 10 years.

 

[coloradotrout]

I forgot to say that of course the plumbing solder melts at a much lower temperature, hence my posting about this option.
Eric

I found Harris plumbing solder at the local TSC but it wasn't the same as the link. It did look like tin, Ag, but maybe some Cu. I'll order some stay brite, maybe the "8" if I can find it.

 

[coloradotrout]

Placed order for Amazon.com

 

[coloradotrout]

Mapp gas and 56% Ag rod from Amazon. We'll see if it worked. A test on a piece of pipe seemed to go ok, so I tried it. It took longer to get to melting temp but the rod seemed to flow.

 

[etpm]

Looks like it worked, great. I hope the leak is stopped. If it is I doubt it will return. Good for you!
Eric

 

[coloradotrout]

Bought these. Will test on scrap. Doubt my mapp gas only torch will melt.
View attachment 4431427

Mapp could not get 2" pc of 1-1/4" pipe hot enough to liquify this rod.

 

[coloradotrout]

Looks like it worked, great. I hope the leak is stopped. If it is I doubt it will return. Good for you!
Eric

It was flowing nicely on my test piece of 2" of 1-1/4" pipe. I was encouraged. I used some brake cleaner in the hydraulic puck and line, and burned out as much contamination as possible. I would have liked to see better flow as I reheated several times to build up the patch. Got new o-rings but want to swap out the pump and get a little better flow rate from the original JD pump. The yanmar is on there now from the replacement engine.

 

[coloradotrout]

It was going to be a week before the plumbing solder arrived and the 56% rods were tempting me . I think I have the older mapp gas which burns hotter than the new stuff.

 

[etpm]

I would have liked to see better flow as I reheated several times to build up the patch.

You got the brazing rod barely hot enough. And every time you reheat it it needs to get hotter to flow. This is in part because the alloy you used is alloying with the existing brazing alloy, and this raises the melting temperature. Still, if the brazing alloy wetted the surfaces then you should be fine. Anyway, it looks like you will have a good patch. Let us know when you get it hooked back up. Make sure all sealing surfaces are clean and oxide free.
Eric

 

[coloradotrout]

Replaced the hydraulic pump from the original engine (this is a replacement). New hydraulic fitting orings, torqued line fittings to spec, and fired it up. No leak!

Now it looks like I may have an oil leak. I'm guessing rear crank seal but not sure.

 

[coloradotrout]

Have ran it for a few hours. No hydraulic line fitting leaks! First time in 20 years!

Now onto some leaks at the FEL connections (hopefully o-rings) the front axle (seal known for leaking), and maybe that oil leak.

 

[etpm]

Have ran it for a few hours. No hydraulic line fitting leaks! First time in 20 years!

Now onto some leaks at the FEL connections (hopefully o-rings) the front axle (seal known for leaking), and maybe that oil leak.

Good news! I was dubious about the MAPP gas torch being able to get hot enough AND being able to supply enough heat but it worked and that's great. Good luck, I hope your repair lasts forever.
Eric

 

[coloradotrout]

Good news! I was dubious about the MAPP gas torch being able to get hot enough AND being able to supply enough heat but it worked and that's great. Good luck, I hope your repair lasts forever.
Eric

It's old MAPP. Saved it from probably 25 years ago, when I was soldering a large sprinkler system manifold. But for grins, I have started a search for a used oxy/acetylene torch. Something else to learn ;-). How does one "heat" but not "cut" is my first question.

Appreciate all the help here. It's nice not seeing dripping hydro fluid and caked on gunk! Looks like I need some o-rings or new hoses on the FEL, and some seals on the front axles. My history is I get it all fixed up, and then something major gives out, and I have to buy new.

 

[mark in portugal]

I brazed many hydraulic fittings on my tractor; mostly I made the fittings to be brazed.
I use oxygen / propane.
The torch has a big cutting head which can be swapped for smaller tips for welding and brazing.