[BRENT in 10-uh-C]

Well Todd, since no one else has responded yet, let's just suppose you cannot find someone. Here is how I would recommend you start as a Do-it-yourself project.

Find a way to plug the water inlet (the one on the side of the block) and use a 15%-25% solution of Phosphoric acid. Fill the water jackets in block and head. Personally I would rather do it seperately but your call. If you have a way of raising the temperature of the acid, it will work more effectively. After a day or two of soaking, drain the acid out into a plastic pan and immediate begin flushing the block out with a high-pressure water hose. Maybe go to a self-serve car wash and use their high pressure wand? With the head removed from the block, this will enable you to see down into each of the water passages and be able to direct the water pressure into those areas to dislodge the rust & scale. Then repeat as many times as necessary to accomplish your goal. If you will filter the acid through an old cloth, you should be able to re-use several times.

Two or three points; warmer acid works better so if you can devise a safe way to heat the block & acid, then the 'pickeling' will happen much faster. Also, understand that Muratic acid is NOT what you want to use in this application. Phosphoric acid is much tamer and easier to neutralize. Stores such as Home Depot or Lowes carry it in their paint department. Finally, to neutralize the acid, mix dishwashing liquid into water and fill the block/head. Allow it to set followed by flushing with clear water.

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