Hello I will help you with your question,
When I get the leaking intake gaskets that fill the cooling system with oil I flush them with Tide by running it with the stat out then removing the upper hose from the radiator and running a garden hose in the radiator while watching it come out the upper hose. Balance the flow so you keep the engine full while the engine is running. Run it til clean.
Block the upper fitting on the radiator where yu disconnected the r hose.
It will take many hours for the system to freeze so you have plenty of time to get it flushed and refilled with antifreeze.
Use the system volume and fill half with straight antifreeze and top off with plain water. Run the engine to mix and you will have the correct concentration
Let me know how I can help you
If you have oil in the system use a cup of Tide detergent before you remove the upper hose and run the engine for 20 minutes with the cap off before you remove the upper hose (careful it will be hot!)
Remove the upper hose and block the fitting on the radiator where you removed the hose.
Run a garden hose at slow flow into the radiator neck and keep just a little flow out of the open end of the upper hose as you run the engine.
Use an old hose to block the upper radiator fitting, there is no pressure you just want to keep the water in the radiator.
Run until the water flows clear.
This procedure is for an oily system, is that your problem?