I recently purchased a 2004 rhino. Unloaded it and after first 10 minutes of riding it started overheating. I washed radiator didn't help, removed radiator had cleaned at radiator shop still did not help with overheating. Next had the head gasket replaced but it still overheats. Also pulled water pump it has no issues. The fan was coming on when it should have but still overheating. Also installed new 12" fan on toggle switch so it can run all the time. Have purged coolant line numerous times. Need some advice. I live in the south so normal temp should be around 200 but radiator constantly boils over.