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**Gregski** · 02-08-2018, 01:55 AM

The one thing I have not changed yet is the flex fan, so I am scratching my head on that. You would think that if it cools at 800 RPM it should cool at 600 RPM, from what I gather, a flex fan flattens out at higher RPMs when it is no longer needed (assuming the vehicle is moving at speed) not at lower RPMs, am I missing something?

02-08-2018, 01:55 AM	#109
Gregski Post Whore Join Date: Aug 2014 Location: Sacramento, CA Posts: 10,809	Re: 71 350 running hot coolant backup up problem The one thing I have not changed yet is the flex fan, so I am scratching my head on that. You would think that if it cools at 800 RPM it should cool at 600 RPM, from what I gather, a flex fan flattens out at higher RPMs when it is no longer needed (assuming the vehicle is moving at speed) not at lower RPMs, am I missing something?