MTFCA Forum

I have an old radiator and likely rust-choked engine that I want to flush. The helpful Australian Youtuber recommends 'Nulon R40', an alkaline solution. This doesn't seem to be available in Tidewater Virginia. What is the best widely-available product?

Wait- wait- I have another question: I have several gallons of generic 'pre-diluted 50/50 Prestone coolant. How should I mix this water to 50/50 Prestone for suitable radiator solution? Thanks!

That Prestone works good after the radiator and engine have been cleaned. Best thing to do is take the radiator to a shop and have it boiled and rodded out It should also have any leaks sealed or a new core. The head should be removed and all rust and sediment cleaned out of the block and head. Then also replace the freeze plugs and seal with water proof sealer around them. New head gasket installed. Then use the 50-50 to keep it from plugging again. Replace hoses and check for leaks around the hoses. Do things right and you should have very little trouble with overheating.
Norm

Thermocure works great. Add to rad and drive awhile. Leave it in all winter if you wish.

Thanks Norman and Big Bird!

When you have the head off to clean out the water passageways in the head and block be sure to carefully clean out the small holes using a ice pick or carefully use a cordless drill to drill out the holes. Quite possibly some may be almost closed with rust. After many years it can happen. Be careful when you do it and go slow. Good luck.

Hi William,
Search the forum ( flushing engine) Steve Jelf has some videos showing his water & air flush system for the engine. I have used it for modern
radiators before & would not use a lot of air on the radiator if you have questions about it's structural integrity. I use a Zepp product instead
of CLR because I'm cheap & I use it straight & run the engine for a while to circulate it well & get it hot ( seems to work better ) then drain
back into the container as you can reuse it for rust removal. It will last a long time if not diluted. I find that 50/50 ethaline glycol mix will
find every leak in your cooling system so if freezing is not a issue I run 75/25 distilled water & antifreeze. Arizona tap water is far to hard to
use in a cooling system, your area may be better?
Craig.

Norman and John, does one have the head checked/milled any time it is popped off?

Norman and John, does one have the head checked/milled any time it is popped off?

It's a good idea the first time if its never been done. A light surface lap @ least to get a true look @ the sealing surfaces.
Every removal - NO.

Next time you are at the grocery or big box store get 2 gallon jugs of cheap vinegar.
Finish the fill with water and go for a drive.
Agitate, circulate, and heat the solution up.
If you love vinegar fries the drive will make you hungry......
It is a very mild cleaner and super cheap.
It is also environmentally friendly (the sludge you get out might not be though).
When it has done its job then drain and flush.
Repeat if necessary as desired.
It's amazing what comes out of old cooling systems sometimes.
It also works on gas tanks and other items needing cleaning where you can't get inside.

HI William,
Vinegar can be purchased in concentrations of from 4% to 80% acetic acid. It goes to say that that the more acetic acid the greater the rust
removal also the cost.
Craig.