Does the warm antifreeze bath method remove carbon deposits inside the engine? Does Demon Clean??

Z best requires two to three applications with brushing and still won't achieve Kamlooper's results. I just spent two days cleaning a 4 stroker and a 2 stroker and I'm still at it. Soaking in solvent alcohol per Harry Higley removes varnish but very slowly.

Does anyone use ultrasonic cleaning, and how are the results?

GoNavy