Additives in radiator stop leak fluids work to remove debris, neutralize acidity, and fill leaks. Some stop leak formulas will include additives that protect your system from corrosion and rust.

Modern radiator stop leak products can work in an old car's cooling system. Cars as old as this Model T Ford didn't use a high-pressure cooling system and ran typically below 160 degrees Fahrenheit.

Here's how you do it. If your radiator's leaking, crack a couple of raw eggs into the filler neck. That's it. Crack the eggs in there, start the car, get it to operating temp, et voila — leak fixed.

If the culprit continues to evade detection, you might consider a radiator stop-leak additive, available at auto parts stores, which seals small leaks — but it’s always better to find and ...

Unfortunately isolating your radiator will not stop a leak, however it will slow it down. Isolating the radiator stops water ...

10 Best Radiator Stop Leaks Updated 31st January 2025. Recombu. Best Lists. Automotive. Car care. Radiator Stop Leaks. Prestone AS145 Stop Leak Repair for Radiators, Heater Cores, and Hoses, 11 oz ...

Heavy Duty Radiator Stop Leak safely and effectively seals internal, external and coolant-to-oil leaks in plastic, aluminum and metal radiators, freeze plugs, gaskets, heads, blocks and heater ...

Cracking an egg or even putting off-the-shelf stop-leak products into your radiator can damage your engine, so it should not be done if you have a high-end or newer car.

While I tend to agree with your mechanic, although 200,000 miles might be a push, I would suggest trying a quality stop-leak product like Mendtite or SilverSeal added to the cooling system.

Kononenko, making his sixth spacewalk, and Chub, making his first, began the excursion at 1:49 p.m. EDT when they opened the side hatch of the Poisk airlock compartment to the vacuum of space.