So at the top of that 90 elbow it is a very slow leak and into the concrete is another slow leak off same elbow... I tried soldering but it just falls right off/breaks even when it becomes a molten ball it rolls right off... could I just pump the hole and that upper part full of epoxy and call it good? Otherwise how do I go about properly repairing that... I tried uploading the image can't for whatever reason but the elbow part is a 90 degree up and it's partly in the concrete from the main line...

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    If you upload the image to somewhere public (e.g. imgur.com) and then edit the URL into your question, some kind person will likely edit the actual photo into your answer for you. It sounds like you are not using flux (or not enough flux) - did you use any? – RedGrittyBrick Mar 13 '18 at 10:07
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    Pumping the hole full of epoxy will do nothing. I assume this is copper water pipe under pressure when in use. You must shut off the water and drain the water out of the pipe to below the level of the joint to be soldered. If this joint is right at the level of a slab you probably don't have a tap lower than that to drain by gravity. I advocate using a wet or dry vac to get the water in the pipe low enough to be able to heat the pipe hot enough to solder. Fixing a leak in a bad joint might require taking the joint apart, cleaning the end and making a good solder joint. – Jim Stewart Mar 13 '18 at 10:50
  • My 1970 tract, slab-on-grade house has no working tap lower than the top of the slab. The house was plumbed with a set of brass gate valves in a box in the ground that would allow draining the water lines, but those gate valves were inoperative within 10 years of construction. If I wanted to lower the water in the lines to below the top of the slab I would shut off the valve at the water meter, open TWO or more taps and use a shop vac on one of the open taps to pull water out of the lines. – Jim Stewart Mar 13 '18 at 11:01
  • I wonder if it would be possible to use a shop vac on one tap to draw some adhesive (e.g., epoxy or super glue) into a joint which is leaking. What I envision is: drain the lines as described above, dry the joint to be sealed with a hair dryer, shut all taps except the one with the shop vac on it, apply the adhesive around the outside of the joint and have the vacuum pull the adhesive into the joint. This almost certainly wouldn't work, but has anyone ever tried it? – Jim Stewart Mar 13 '18 at 12:25

You need to explain what the pipe is for, what fluid is inside, where is it located. From your writing you are probably looking at having to do some excavating to gain access to the pipe. If you are trying to solder a line full of something like water, It shows that you have no experience to make the necessary repairs and it time to call for professional help before you do something that can hurt you or can't easily be fixed


Copper in concrete can be bad news, from your description it sounds like 2 or more problems. First the pipe needs to be dry free of moisture, second the copper needs to be clean a fine sand paper on the outside of the pipe and inside of the 90 can be used to get the copper bright and shiny, make sure to use a water based flux that is safe for drinking water. Next heat the pipe first until the solder starts to melt then move the heat onto the 90 this helps the solder to wick into the joint. As I said at the start copper pipe in contact with concrete can be a problem and the pipe itself may have been degraded to the point it is full of pinholes and needs to be removed and replaced. With out a photo we can only guess at this point. I will usually stuff copper that has been wet with white bread no crust and create a plug to keep water out of the joint then remove the ariators on a down stream faucet and flush the bread out of the line this method helps keep moisture from getting into the seal area preventing leaks.

  • tinypic.com/r/nnnp10/9 here is the pic of the water line into the house on this 1 90 degree joint it leaks from the top as well as from the bottom part out of the concrete like pin hole leaks from the same joint there the pump house I can shut off and there is a spot I can hook up a hose to drain which is lower that the line evacuating water doesn't seem to be an issue the pic is sideways but it is vertical when it comes out – Justin Mar 14 '18 at 12:12

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