Radiator Replacement or NOT?

[Cuda 72]

Prior to parking this car (about 12 yrs ago), I had a problem with it overheating- I think it was inherent for 340s??? At the time, I had it flow checked, put in a new waterpump, therm, and added a new clutch fan, but still had a problem (not sure if there's a better fan shroud out there). I've considered aluminum replacements, but looking for some input.

[moparmaniac59]

How does the radiator cool things when the car is moving?? Does it only get hot when the car is stopped? If it cooled OK when the car was moving, then one of the problems is with air movement across the radiator. The block itself may have restricted coolant passages from crud build-up over the years. A bigger radiator may help by providing more cooling surface. How close is the fan to the radiator surface? There are a few variables to the equation such as the fan type, blade number, water pump type, radiator size ect. Figuring out where the problem lies is the first part.

                                            Matt B.


                                 

[Cuda 72]

It would tend to overheat when I wasn't moving. The fan was probably about 5' from the radiator and just outside of the shroud. I'm having the engine rebuilt, so I'm sure that will help some. I'm thinking, if the original radiator has good flow, I can try it with the rebuild. Worst case, I could replace it later. Thanks for the feedback!

[Chryco Psycho]

Typically a factory brass rad & a clutch fan will cool extremly well unless the rad has a flow problem or the clutch is slipping

[Aussie Challenger]

If the motor used to over heat before and you are going to the expense of rebuilding the motor it would be cheaper to have your radiator cleaned out before refitting so that you don't risk cooking a fresh motor.
I would make sure that the fan is half way into the shroud and check the clutch operation.   

[moparmaniac59]

I would definitely move the fan in closer to the radiator. Five inches is way too far away. I'd say 2 inches is more like it. That alone should make a significant different. You can buy a spacer from various places to help close the gap. I think Summit or Mancini racing carry them!!


                                              Matt B.
                           

[Aussie Challenger]

The fan needs to fill the hole in the shroud and not be too close to the radiator so that it can draw air from the whole radiator, the fan should in effect "plug up" the shroud hole.   

[72 Cuda Replica]

Stumbled onto this old thread and not sure how you may have resolved your issue but:

Over time the fins in copper-brass radiators are prone to losing their louvres to corrosion.  At that point, the heat transfer ability is severely reduced.  The radiator looks OK and may be flowing coolant well, but still insufficient cooling.  Modern aluminum radiators are much less prone, but not immune.  Road salt accelerates the process.

The three big causes of overheating - assuming everything is OK with the engine - are eroded/corroded louvres in the radiator fins, plugged or slime buildup in the radiator tubes, or malfunctioning fan clutch.

Trust me, I'm a heat exchanger engineer for a major auto company.

If you don't care about originality, go with aluminum.  Lighter weight, better life span, and just as good cooling.  Aluminum requires a little more fin area for equal heat exchange.  That is generally accomplished by using what's called higher fin density, and also possibly a little thicker core matrix.