Question: Flushing cooling system

[vetdaddy]

Looking for good advice from those more experienced in reguards to flushing the cooling system on my 1972 454. The radiator on this model does not have a cap but the metal reservoir does.

Any advice on what the methodology to flush as well as what to flush with (some have said to add liquid dishwashing detergent and let it run to clean).

THANKS!!!!!!

 

[Hib Halverson]

Open the radiator drain valve.
Remove the two block plugs.

Let the system drain.

Once it's dry, close the radiator drain, stick a hose in the expansion tank and turn that baby on such that it fills a little quicker than it can drain out of the block drains.

Fire the motor and run it for several minutes with the flow into the fill tank just a little more than what can drain out of the block. When I do this with my 71 BB, I have the water just barely overflowing the tank filler neck.

Shut the motor off and, once again, open the radiator drain and let the system run dry.

Replace the block plugs, close the radiator drain and refil with a fresh load of whatever coolant mix you use.

The other things I'd do is assess the condition of all your hoses and, if the thermostat is more than 10 years old, while you have the coolant drained, I'd pull the water outlet and inspect the 'stat. Either replace or reuse the 'stat and install a new thermostat gasket.

Get your radiator cap tested. Replace the cap if it flunks the test or if its two seals are worn.

Lastly, take a look at the radiator cap seal seat in the expansion tank. Often, with cars that old, the aluminun surface will be pitted and damaged such that the cap will not properly seal when the system needs to build pressure. If that's the case, make repairs as necessary.

Have fun.

 

[vetdaddy]

I can't thank you enough for taking the time to post that response.
THANK YOU!!!!!!!!!!!!!

 

[Hib Halverson]

You're welcome. Glad to be of service.

 

[vetdaddy]

Bad news- While starting this project, I found the the lower radiator plug to be corroded and frozen in place. It also appears that a previous owner damaged the radiator when trying to remove the plug and my reattempt did not help the situation- some old JB Weld like product fell off exposing a pin hole leak.

Now my small project has grown!!!!!!! Now I have to decide on replacement vs repair of the radiatior. If I replace the radiatior, I am considering a Be Cool aluminum model.

Any advice on product selection would be appreciated. Please keep in mind that a "non-matching" radiator is not an issue with me. For cooling, I would prefer performance over originality...........but..........always open to advice. Thanks

 

[Key West Jack]

Take the radiator to a good radiator shop. They will clean it, test it, replace the drain valve and paint it. I will be better than new. You will find it is not that expensive a job and you will get back a good radiator. If you decide on a replacement I had great luck with a DeWitts for my C4. DeWitts - Home

 

[GaryS]

If it is the original radiator, it is at least 36+ years old. I seem to recall reading on DeWitts website that they can redo your rad, keeping as much original as possible. No reason repairing an antique rad imo. Fwiw, I have a 72 LT1 and, when the time comes, I am heading to DeWitts. I had a 66 that would always overheat and a DeWitts repro aluminum radiator fixed my problems.

 

[vetdaddy]

Thanks for the replies.

At this point this is where I see it- The radiator is not original to the car- so why repair it. My water pump has the wrong date code so was obviously replaced at some time and the fan blade is also not original. The only original parts to the cooling system are the fan shroud and the fan clutch. Sooooooo- Probably will go to a Dewitt's aluminum rad, a Stewart's water pump and probably electric fans. I'll save the radiator shroud and fan clutch since they appear to be the only original part. The nice part is that all of these changes- simple to reverse if someone chose to replace them with properly dated OEM products. Yes, a little more money into the car, but like I remind my wife- still cheeper then being addicted to crack, hookers and penicillin!!

 

[Evolution1980]

I don't have one myself, but I would also recommend DeWitts. I can't recall ever hearing anything bad about them, but lots of good. Considering that bad news travels faster, I'd say that's a pretty solid endorsement.
Good job on identifying the issue and choosing the proper fix ("replacement").