Plain old cooking oil works pretty well as a solvent and its not dangerous. When we got rid of our Safety-Kleen parts washer, they notified the Texas Environmental Commission which they routinely do to retaliate against former customers. When the TECQ found we were using Crisco cooking oil, they couldn't think of any regulation we were violating. We even use it to spray trailers before we load pre-mix paving materials so they don't stick. It makes the trailer smell like a hamburger, but thats ok.
