Leaky High Mile Miata Needs Low-Buck Repair

Dear Car Talk

Dear Car Talk | Mar 08, 2018

Dear Car Talk:

I have a 1991 Mazda Miata that I bought new nearly 27 years ago. It has 230,000 miles on it and, believe it or not, is having its first problem: a leaky radiator. The radiator is leaking all around its top seam, so it needs to be replaced.

My problem is that I cannot afford to do it right now. I've been driving it with the radiator not full, because if I fill it, it just leaks out. The temperature rises to normal and has never gone above that. Am I doing any damage? In a Quandary -- Ron

Wow, 230,000 miles. You're only 20,000 miles from the moon, Ron. The question is: Are you going to make it? Might be time to fire the retro rockets.

If you're not currently overheating, then my guess is you're not driving very far or very fast. If you really heat up this engine, the cooling system won't be able to hold pressure, and the car will overheat. So keep that in mind, and don't plan any road trips to Quito, Ecuador.

You'll also want to keep a close eye on the coolant level. If it drops too low, you could overheat even on short, slow trips. And last time we checked, engines cost much more than radiators.

So my first suggestion would be to use your credit card and fix it. If this is your only means of transportation for the foreseeable future, you might not want to risk it.

If you really can't fix it now, you might as well try one of the radiator stop-leak additives you can find at your local auto-parts store. It works kind of like a blood clot: You put it in the radiator, and it circulates around; when it escapes through the leak (when it hits the air outside the leak), it hardens. And then it builds up until, if you're really lucky, it kind of patches the hole.

Does it work? Sometimes. And for a while -- it's not state of the art, Ron. It'd be like attaching pump-organ pedals to your heart instead of implanting an electronic pacemaker. But desperate times call for desperate, and really cheap, measures.

So give it a try. If it doesn't work, all you've lost is eight bucks. And a delay of a few more Bitcoin trades until you can save up enough to replace the thing. Good luck.

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