Just wondering any way to test this?

I was having cooling problems while in Arizona in my 260E. I have ordered a new viscous fan as it was not working, but I am curious about the radiator?

Any way to 'test' it?

Thanks

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k