Few Repair/Maintance questions for new RV owner

I don’t know if you have tried this, spray the radiator and the stuff in front of it with simple green or dawn dish washing soap (it works better on a warm engine) and let it set for a while. Next hose it off with a LOWPRESHER spray if you use to much presser you can damage the fins on the different coolers. Next build a duct that forces all the air coming through the grill through your radiator. Do a search poor cooling and airflow is a common problem.
Bill