Puddle Pushover

Aug 09, 1997

RAY: A guy writes: Whenever I went through a puddle I would lose my brakes.

TOM: Did he have to back up and pick them up?

RAY: Better than losing your shorts. He would lose his brakes. He said, "I went to one mechanic after another. Everyone said the water is getting on the linings in the back. They put new linings on. They made sure the plugs were in, where the adjustment holes where. When that didn't work, they put new pads in the front..."

TOM: He didn't buy the underwater package when he bought this car?

RAY: He bought the Cousteau package. He said, "For as long as I've owned this car, everytime I went through a puddle I'd lose my brakes. The car just didn't want to stop."

TOM: That's common.

RAY: "Then five minutes later, it was like my old 50's and 60's cars that you had to ride the brake when I got out because water had gotten in." And I said that doesn't happen to modern cars, at least not so much anymore. He said it didn't take much of a puddle to do this. So I took a drive around with him and the brakes seemed okay to me. He said, "Oh, and another thing happens once in awhile, when I go through a puddle, I also lose my steering."

TOM: And you said, "Oh -- why didn't I think of that before!"

RAY: That's exactly what I said. As soon as he said, "Oh I lose my steering, it gets very hard to steer." I knew immediately what was wrong with his car. The solution took about 5 minutes.

TOM: Not thinking about the solution, but actually implementing the solution.

RAY: Performing the solution took five minutes. The guy called back after the next rainstorm and said, "I drove through puddles all day; soaked pedestrians throughout the city by driving through big puddles. My brakes worked great."

What did we do to his car that took 5 minutes that solved this problem? The hint is: His car is a diesel.


RAY: Here's the answer. What was wrong is that he had a loose power steering belt.

TOM: Let me say it. What would power steering belts have to do with losing your brakes, Doctor? Funny you should ask!

RAY: Well, glad that you asked. Actually some of the other cars that GM makes, and not just GM, but other cars that have had this configuration -- have instead of a vacuum or a vacuum powered booster that is operated by engine vacuum, they have a power brake that is operated by hydraulic pressure. Where do you think this power pressure comes from? The same pump that runs the power steering.

TOM: You don't say!

RAY: And what was happening with this fellow is that when he went through a puddle, is that the belt, which was loose, would begin to slip. And what he would lose would be his power brakes. He would lose the power brakes and step on the brake, the pedal would feel very hard, but the car would not stop. And it felt to him like the cars of yesteryear when the brakes were wet and you'd step on the pedal it would feel hard, but the car wouldn't stop because the water was actually reducing the friction between the linings and the drums, or the disks.

TOM: And he no longer had power brakes.

RAY: All he knew was that there was something wrong with the brakes because the car wouldn't stop. When he mentioned that of course that he was losing his power steering, I said, "Ah hah! -- the belt must be slipping." And what we did was tighten the belt. And that fixed the whole thing.

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