When is a recore needed?

[7gen]

I'm in the learning phase with auto repair. My 76 Eldorado is in good shape, seemingly. I took it down Route 66 a few years ago, then across Route 50, so it runs fine. No overheating issues.

I have been reading about radiator recores here. The car has 50K original miles on it now, with the original radiator. How would I tell if it needs to have a recore? There is an old-school place near me that specializes in classic car radiator recores, but he is not going to be there forever. Would it be a good idea to maybe bite the bullet to do a recore now, even if one isn't really necessary at this minute, and be set for the next 20 years or wait until it shows whatever signs and probably be forced to get a replacement radiator at that time?

So I guess that's two questions - what signs indicate it is time to do a recore and would you do one before those signs showed up if a good recore place was available as opposed to maybe not having that opportunity later on?

[TJ Hopland]

Most of the time people get them done because of external leaks.  Occasionally they get done because they are internally clogged and just not cooling.  For the not cooling part they can also sometimes be 'rodded' which is where a shop will remove the tanks and shove some sort of rod through the passages to try and clean them out. 

I would not do either process just based on age,  I would wait for some sort of symptom.   

[hornetball]

In the meantime, it is good maintenance practice to drain and replace the coolant to prevent corrosion/clogging from getting started.  That's the key to keeping your cooling system in good shape.  Every other year for the old green coolant that came in the car originally.  Newer formulations are supposedly good for 5 years.

[fishnjim]

When it no longer can be repaired.
Adhere to hornetball's advice.   
EtOH2(ethylene glycol) oxidizes and creates acids which eat the radiator metals.   There's extending stabilizer that you can add also, but best to just change is at least on 5 years.   I prefer to buy concentrate and dilute with distilled, not tap, water.   They sell it 5050 now but it's more pennies.   Don't want mineral salts to build up inside.   Reduces heat transfer and flow.   If you look in there and it has whitish things growing then probably a good flush is needed too. 
The older radiators were much thicker and had more solder than what's out there today, so if they're maintained they should last a long time.

[7gen]

Much obliged.

I change the green stuff every two years. I got the car in 2014 and initially, did three drain/fill cycles to clear any rust color out of the radiator. Just a hint of color on the second, no color at all on the third. From that time, I follow the FSM and do it every other year. No color since.

It got me across the Mojave from Needles CA a few years ago, 107.9 degrees that day. Then back across Nevada on I80 coming home, so it has seen some heat. No issues, so I won't look for problems. Thank you for the advice!!

[wheikkila]

I would not Recore till I had to. When you recore they have to match what you have. Sounds easy, but you never know what can happen when you take item in to be rebuilt. Sometimes they come back worse then you took them in.
Thanks Wayne   

[76eldo]

You should buy a used one that has nice tanks and get it re-cored and put it on a shelf for the future. It won't go bad.

[35-709]

You should buy a used one that has nice tanks and get it re-cored and put it on a shelf for the future. It won't go bad.

  Bingo!

[The Tassie Devil(le)]

I agree with the rest of the comments.

If you look at the picture and try and enlarge it, you will see that the fins in the front of the radiator, down low, behind the hood latch support, in my '60 CDV were totally rotten, and starting to degrade, but the radiator kept the engine cool, and didn't leak.

It was like it when I purchased the car, and still like it when I sold it many years later.

The top section was protected by the metal of the hood, but the part behind the grille was  the worst.   It looked like it was attacked by thousands of stones that entered through the grille openings.

Bruce.