Cleaning melted aluminum from seized cylinder bores 
      
A seized piston is caused by a lean fuel mixture. In a cylinder with a chrome bore,

Honing out the melted aluminum is a bad idea. One way to remove aluminum without removing steel, or chrome, is with muratic acid. This is dangerous, and should only be done in well ventilated areas, using proper safety precautions.
       Muratic acid can be obtained at a drug or hardware store, and is water soluble.
  I have been told It is  used to clean swimming pools.
      Pour a small amount into a container to dip your Q tip into, and swab some onto the melted piston bits in your cylinder. It will bubble up, and stink, as it eats the aluminum. keep adding fresh acid and cleaning off the old with water to remove all the melted piston. Do not breath the vapors.  You can speed the process by scraping witha a small sharp tool.   Do not allow the acid to come into contact with anything other than plastic, steel, or chrome cylinder plate, that you do not want destroyed. .
        
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