hi, I did eventually find the person advertising the viscous conversions (Mike Murdoch) for the Humvee. I purchased one - I don’t know if I had a bad viscous unit from him or not but mine stays on all of the time and does not cycle. It is as noisy as the fixed fan that I removed (Saudi/NY Humvees), so there is no advantage in having a viscous. As someone previously said, anyone other vehicle I have had or worked on including tractor trucks, when fitted with a viscous they come in and out with the temperature.
Has anyone else purchased a viscous fan for a Humvee from Mike Murdoch? If so, what is your experience with the fan, does it cut in and out or is it permanently on?