any parts degreaser solvent recommendations

[John Larson]

Gonna be hard to find a suitable (and effective) cleaner for the price, 2
bucks a gallon, of solvent.  In a 50 gallon unit, 20 gallons should be fine,
maybe 30, but you shouldn't need anywhere near 50. There are a number of
heavily advertised substitutes out there, though.  Many products need to be
heated to work properly.  A rudimentary Google search yielded this one that
sounds promising:

http://www.graymills.com/SourceParts/cleaningsolutions.html

HTH, John