What Mr. Mueller discovered is that sodium silicate is the designated agent of death for cars surrendered under the federal cash-for-clunkers program. To receive government reimbursement, auto dealers who offer rebates on new cars in exchange for so-called clunkers must agree to “kill” the old models, using a method the government outlines in great detail in its 136-page manual for dealers: Drain the engine of oil and replace it with two quarts of a sodium-silicate solution.
