From eggs to additives, Tom and Ray offer ideas to help Lynne plug a leak in her radiator.

Dear Car Talk

Dear Car Talk | Jun 01, 2007

Dear Tom and Ray:

I recently found out that my '88 Subaru needs a new radiator because there is a place where it is spewing a small amount of water, causing my motor to overheat about every 7 miles. I asked my son if it safely could be put off for a while. He said I would have to get a new radiator, but it could be delayed a bit if I put a beaten egg into the radiator and then drive it for a while. He made me promise to have the radiator replaced. My question is this ... should I worry? He is a Black Hawk crew chief in Iraq, on his second tour. Do you think he is fixing helicopters with eggs? Was he just having a laugh on Mom, or is this really an option? -- Lynne

TOM: Trust me, Lynne. If he ever started putting eggs into Black Hawk helicopters, his platoon mates would get him permanently reassigned to latrine duty.

RAY: This is what's known as a "repair of last resort." Or, in layman's terms, something my brother would do.

TOM: Let's say you overheat late at night, in the middle of nowhere, and you happen to have a dozen eggs -- who knows why? Maybe you're Martha Stewart and you're on your way to make a frittata.

RAY: Anyway, you realize that you've got a radiator leak. If the leak is small enough and you drop a raw egg into the radiator, pieces of the egg might "cook" and harden, then clog up the hole that's letting coolant leak out. Maybe.

TOM: People have written to us and told us this has worked, at least temporarily. And we've heard similar stories about large quantities of black pepper. But duct-taping yourself to a tree limb also works if you want to keep from stepping in dog doo. That doesn't mean it's the best solution to the problem.

RAY: If you're in a position where you can't afford to replace the radiator now, Lynne, you'd be better off using a commercial additive that works in a similar way. We've had some success with something called AlumAseal (although there are lots of similar products). AlumAseal consists of small pieces of aluminum that turn into a muddy blob when tossed into the radiator. Then they follow the flowing current to the hole, and harden once they fill the hole and are exposed to air. That may be a little more long-term than the egg.

TOM: But your best bet is to just get the radiator replaced. Overheating can do permanent and expensive damage to your engine, so you want to overheat the engine as little as possible. And if you're overheating every 7 miles, it's probably time to skip the temporary solutions and fix it for real, Lynne.

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