Cold Case Radiator Shroud?

Got my radiator back in. Runs much cooler with the new shroud. Still only in the 70s here, so no real test. Doesn’t overheat idling now, so that is a very good sign.

I think my shroud was the problem all along. My fan was completely inside the shroud I made. Folks had told me that the fan needed to be half way out of the shroud. I discounted that advice, since every car I have seen for the past 30 years had no exposed fan blades. They were all well inside the shroud.

I have looked at many newer engine driven fans on cars lately and have noticed that the fan blades are shaped very differently. I don’t understand fan design, but obviously (now) it matters. It appears to me that the fan design must match the shroud design for it to work properly as a system. Since I was using an older fan designed for the 1/2 in 1/2 out shroud, I was mismatched.

Don’t know if I could have also got a later model fan designed to be fully enclosed and solved my problem instead of switching the shroud.

Now I am running a Cold case radiator, Hayden 2947 fan clutch, 7 blade Mopar truck fan, flowkooler water pump, Milodon high flow thermostat, and upside down /6 shroud, and all seems well. Summer will tell....

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