Can you recommend a rust inhibitor?

Dear Car Talk

Dear Car Talk | Oct 01, 2002

Dear Tom and Ray:

I am the proud owner of a 1974 Alfa Romeo GTV. I know what you're thinking -- I'm nuts. Honestly, I'm not. Alfas are actually very easy to take care of -- they have simple engines that even a dope like me can work on. My problem is rust. I really want to stop it from eating my precious Alfa. Recently, I read about electronic rust-prevention systems. One system allegedly creates a "cathodic" protection layer or some such thing, while another uses more attractive anti-corrosion pieces to keep rust from eating one's car. Do any of these systems work? Can you recommend one? -- Gavin

TOM: No, and no.

RAY: The advertisements always sound so convincing. They talk about "sacrificial anodes" that offer themselves to the rust gods so your car won't have to.

TOM: I think maybe Gavin's Alfa is the sacrificial anode for all of the other cars in his neighborhood.

RAY: Well, the ads always say that these devices are used successfully on oil tankers and storage tanks. And they probably work great on those things. But they don't work on cars.

TOM: Why? Probably because cars aren't built like oil tankers. Maybe it's because the steel isn't contiguous, and there are bushings and O-rings and plastic that get in the way of the flow of electrons. I don't know. But I do know that you're wasting your money if you buy these things, Gavin.

RAY: The factors that make some cars rust faster than others are: the quality of steel used (if you look carefully, you might see the words "Swanson Hungry Man" stamped into the Alfa's sheet metal), the rust-prevention treatment given at the factory (probably none for a '74 Alfa) and the environmental conditions the car has lived in (moisture, road salt, garage).

TOM: Unfortunately, there's not a lot you can do now. Your best bet is to keep the car clean, garage it if you can and fix the individual rust spots as they pop up. Rust spreads, after all. Kind of like a bad smell.

RAY: And instead of wasting your money on these quack products, save up for a good full-body restoration done by a reputable body shop. If you have to do that every 15 or 20 years, that's not so bad, right?

TOM: Right. My brother's wife would be happy if he had a body restoration -- or even just a paint job -- every 50 years.

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