Shroud dude, get that shroud!
A/C work is part of my job. Ya, A/c units come with fans to cool the outside condenser coils, & the fans have shrouds as well.
I like to think of them as dividers! The divide the air from one side of the fan from the other side. One of the cool things we show the new guys is how much the pressure increases if you happen to lay something next to the condenser coils and block the air flow.
It has the effect of reducing the area of the coil & the temps & pressures go up.
The same thing happens if a tech installs a new outdoor fan motor and does not mount the fan at the proper height in the shroud.
You need the air pulled through the radiator, guy. Get that shroud.