Should a radiator back flush be done?
If so, what is the best practices?

I was considering putting Prestone radiator flush into the radiator and running the car for a half hour. Then it will be back flushed.

Is this advisable?
Should a back flush be done at a particular time?
Are there any cautions when doing a back flush?
Should the thermostat be removed?

After the flush,should anything be added to the coolant system aside from water and anti-freeze?

Any other advice or insights?

 

You can try it, but if the radiator is the original from the 60s it might be time to have it re-cored. It'll be all copper, so this is a fairly easy thing to do, albeit costly with the price of copper being what it is.

 

I did back flush the system, and the result was better than could be anticipated.


I went in via the heater core hose and opened the heater within the car.
I did NOT use any radiator cleaner nor ran the engine previous to the flush.
It was flushed cold and without any additives.


The garden hose was turned on slowly at first not too have too much initial water pressure flow. Then it was increased. Nothing came out at first. ( A rag was put atop the body in front of the radiator to "catch" any possible debris/rust ).


After a bit of water pressure and time, the flow of water started to come out of the plastic spigot inserted into the radiator opening from the back flush kit. Clear and then greenish tint from the anti-freeze. The water pressure was increased a bit, and the system flowed completely clear! Only one little bit of something came out! Other than that, clean and clear!


Given that result, there appears to be no reason to put any radiator cleaner into the system and flush it out again. Why take a chance with the current good results...


Now, what should be added to the system after this flush beyond water? I was thinking an additive that makes the cooling system run cooler since it is an aluminum engine and radiator that is suppose to work better without anti-freeze coolant. And mapre some Barr's lubricant that lubricates the water pump seals.


Your thoughts and experiences please!

 

I wouldn't use that stuff, a 50/50 mix of anti freeze and water is all that's needed. There are lubricants in the anti freeze.
I've been running the 50/50 mix in My Bentley and Jag for more the 20 years and have had no problems.
As with anything, maintenance is key _ change your anti freeze at least every 2 years.
Some say you can leave it in for 5 years, but I think that's pushing it.

A good test to see if you rad is healthy.
Take your car on a long drive and get it good and hot.
Turn the engine off and snake your hand in around the fan and move it around on the "flat" of the rad matrix.
It should feel warm all over, any cold spots indicates blocked tubes.

 

Understood. 50/50 mix it is.

 

Here's pic of the the way I did the back flush....just FYI