For a quick radiator leak fix, you can crack a raw egg into the radiator. The egg seals any holes and you can continue on.
This was on an episode of “Myth Busters” and it seems to actually work.
Hot breakfast cereal, Malt O Meal and oatmeal also work fine. The trick is to use something that will conform to the irregular hole(s) and be held in place by the water trying to get out. Egg white, oatmeal, Wheaties, Cornflakes; something that gets soft and won’t hurt the water pump but will plug the hole.
Off-topic tip.
Keep extension cords from getting tangled: Drill a hole near the bottom of a 5 gallon bucket and run the plug and about 2 feet of cord out the hole and coil the rest of the extension cord inside the bucket. Set the bucket next to an outlet, plug it in and feed out as much or little cord as you need. A 5 gallon bucket will hold a lot of joined extension cords. When you’re done simply coil the cords back into the bucket. No fuss and no tangles and it’s easier to carry one bucket than multiple cords.