The mysterious Leaking Sink has been an ongoing problem.

This particular issue has been plaguing us on and off over the last two years.  To say it’s mysterious would be an understatement.

We will get a small amount of water under the bathroom sink, and then nothing for weeks on end.  Once I noticed this happen, I placed a tin pan under the sink.  We can go an entire camping trip with no issue.  Then all of a sudden it reappears.

I’ve tried isolating the leak each time I find water in the catch pan but to no avail.  I thought that once I might have had water from the hot side of the sink. I’ve tightened connections, including the connections to the faucet, the p-trap, and sink drain. So far, this has not made a difference.

Now, it’s interesting to note that this is a Kohler faucet I installed back in 2018.  It is a very nice residential faucet and I don’t think the faucet is the issue.  I believe the plastic fittings on the pex lines are the issue.

So, my solution is to remove the pex lines at the faucet and replace them with braided 1/2″ npt braided line.  The braided lines are 18” long.  I will connect them to new water shut off valves.

I could have gone with braided lines that were 1/2″ on one side and then 3/8″ on the water valve side using a one-piece water valve.  Instead, I opted for using a 1/2″ connection on both sides of the braided water line. 

I will screw the braided line on to the 1/2″ male threads of the water valve.  On the opposite side of the water valve, I will screw on a 1/2″ pex fitting.  Then I will insert the barbed end into the pex line and crimp it.

The reason I am using that method is versatility.  If the water valve or the braided line needs to be replaced, I only need to unscrew the lines.  There will be no reason to cut any pex fittings.

So will this fix my problem?  It all depends on what the problem really is.  There are some other lines under the sink that I believe have something to do with the black tank flush.  That is the only other thing that could cause an issue BUT our problem surfaces when we are not using the black tank flush.

If this fix fails, then I will pull the faucet and see if by some freak chance the faucet itself is the issue. Stay tuned to our youtube channel to see a video on this repair sometime in the near future.