90 Astro blown head gasket. Vehicle had no thermostat to avoid overheating and used. White smoke present, increasing w/ thermostat. Used half bottle of K&W fiberlock into radiator cap without thermo and ran 20 min at idle and white smoke reduced. Waited until cool placed thermostat and ran at idle fir 20 min and waited until cool for 4 times and all smoke is gone. Each cycle reduced smoke substantially until it was all gone.
i tried liquid glass in my car 2 times didn,t work tried k&w car quit running hot done drove over 500 miles car still running good love it works highly recommend it