Most engines with cast aluminum top out at about 40-50% aluminum recovery. So ask your yard if they have a cast aluminum engine price or a 40% aluminum breakage price. Then do the math and see if it works out good for you. Because alumimum is in the tank right now the prices will be less than you'd hope for but still worthwhile if convenient. Predominantly cast iron engines pay less than that. Also look around to see if you have any core buyers locally. If so they may have a price sheet for the various engines they buy as cores. As cores engines can go into the hundreds of dollars for some not too uncommon ones (same to all of this for transmissions).
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