How to clean out radiator fins that are clogged with gunk?

[oosik]

Bill - I can vouch for the effectiveness of radiator fin combs. Last place I worked - manufactured VERY large air handling units. We had "radiators" large as the side of a normal house. 8' high by 20' long was not unusual. During the normal process of manufacturing - fins would get bent. Those "fin combs" corrected any "oopses".

 

[Hay Dude]

Big NO! to the pressure washer. It will tear up any radiator!

Yeah like don’t use a pressure washer set on 3000psi at an angle and flatten the fins,
but 1000-2000psi straight on is harmless.

 

[tradosaurus]

Reminds me that I need to get a can of condenser cleaner for my outside a/c unit.