I own a 1985 Vanagon that wants to run hot last 30 days.

I can drive forever if the heater is on.....needle just above idiot light on dash for water level (I used to run just below this....).  Also my engine, if overheating, can be cooled down significately by stopping only 5 minutes.

*My radiator was OEM replaced 2 yrs. ago but I have put in 2 treatments (1 per year) on "alum. seal" into that new radiator.

?Help.  Need to cool my engine running temp. down B4 I hurt my engine.  What is the best way to clean this radiator out WITHOUT going to the radiator shop.  That may be my next step.

Thanks for inputs

Larry