Our upstairs bathroom had been leaking water from a drain line for some time.  It took us some time to figure out we had this problem. We called a wonderful plumber and he had to repair three badly glued sewer line pipe joints.  It appears that the person who installed the sewer lines failed to apply enough glue to the inside of the joints but rather made the outside of the joint look quite nice outside.  I consider this an attempt of a trades person to sabotage our track home, possible out of spite due to it’s high cost or ignorance.  (We have one other instance of alleged delayed track home construction sabotage.)  Water came from an upstairs bathroom over part of our laundry room ceiling and down the outside wall where it rotted out a small wood wall footing.  After all the plumbing repairs were completed to the upstairs bathroom I had to face closing up the ceiling and walls.  A significant problem stalled any effort.  Next to the main sewer drain line coming down from the second floor bathroom at main floor slab level was a short wall footing that had rotted out.  All that was left was a singular rusted threaded bolt sticking out from the slab and a 1/2 inch course thread nut that could not be removed.

I first tried to apply gas torch heat because an internet web site promoted this as a viable method for removal of the nut.  I even applied ice to the bottom of the threaded shaft thinking that that might help break loose the bolt when I torched that nut.  This did not work.  I tried twice.

One night I remember hearing about nut crackers.  It took a whole day to find one   It is a Craftsman Universal Nut Cracker CMMT14117 which cost me just over $16 with tax at Lowe’s.

It took me three tries to best figure out how to work the tool.  Soon as I tried the tool the first time, I came to realize that I needed to hold the tool in place with a crescent wrench.  The tool is clever because the top and bottom sides are flat for applying a wrench.  I used a socket driver to make tightening the nut cracker easy.  This method worked.  I did have to apply a lot of pressure to the socket wrench handle to turn the nut cracker threads as the device tightened against the nut.

I knew that I was going to have a real problem cleaning up the bolt threads.  When the nut finally cracked apart by applying the tool, It did not fall apart but widened a bit due to one side being open from the tool wedging the nut apart a bit.  I was able to back that nut off the threads quite easily.  I quickly realized that the nut was helping to clean those threads to some degree as I removed it.  I really do NOT want to buy a die to clean up those threads  because a (14 piece) Dewalt set would cost me $60.  I put a wire brush tool on my drill and cleaned the bolt threads as best as I could.  My thinking is to put a new (1/2 inch course thread) bolt and hope it will do the cleaning.

I next used this combination of techniques to clean the threads:

• I purchased a stainless steel (I like better replacements) nut: 1/2 inch, coarse threads and used it to clean the threads by winding and unwinding it up and down the corroded bolt threads.  Almost every time I performed this trick, I was able to move the bolt a slight bit closer to the floor.
• White vinegar soaked napkin squeezed up against the threads when I was away from the project.  I did this once and then cleaned the threads with water.
• Drill with a wire brush attachment used to really dig into the threads to remove any removable coats of rust.

• Applying Liquid Wrench to the threads and winding the bolt up and down those threads.

After spending a couple of hours cleaning the threads to the bolt coming out of the foundation, I was able to easily thread the bolt down to within one inch from the concrete floor. Because a 2″ by 4″ board measures close to 1 and 3/4 inches I now can place a replacement board into that spot and bolt it in place.  The replacement wood piece has no vertical wall studs laying upon it.  It is only there offer a backing for dry wall screws.

Note the corrosion in the threads at the top and bottom of the bolt as seen in the image above.  The cleanest threads are where the pre-existing nut was.  My treading and un-threading this nut really gave me confidence that a new replacement nut will definitely work.

Summary:  The use of the heat method failed for me. What really worked was using a Nut Cracker.  It is way more safe than using a propane torch and resulted in perfect success.  In fact, being able to back off the nut after it cracks, helped to clean the threads above where the nut was attached.  I did not have to buy an expensive die to clean up the treads but just use a high quality nut and chemicals to clean the threads.

Posted August 10, 2019
Updated August 11, 2019
Updated August 12, 2019