In addition to the potential damage to surface finishes, the spray from a pressurized stream of water from a power or pressure washer is likely to penetrate the seals, bearings, bushings, and material joints of any 100-year-old machine. This displacement of corrosion-inhibiting lubricants will leave corrosion-promoting water in their place. Spray and condensation are also likely to be present in the engine/drivetrain internals. If the engine runs, running the machine at operating temperature for a period of time should vaporize any water. It is vital to then change all the oils. Then drain the fuel system and either leave it dry, or better, replace the fuel with a stable, medium such as clean, filtered kerosene.
As with paper conservation, gentle removal of contaminants is recommended. Whatever methods are used to prepare the machine for exhibition, corrosion prevention should be one of the final steps.
I'd suggest checking with area museums that preserve machinery.
Clifton Patrick
Town of Chester Historian
119 Brookside Ave.
Chester, County of Orange
New York 10918
chester-ny.gov/town-departments/historian/
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Clifton Patrick
Town of Chester Historian
Chester, NY
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