Guilty of Lugging

May 10, 2022

We have a wonderful new puzzler. Not one of the normal, lousy ones... 
The question is wonderful. I'm not so sure how wonderful the answer is. The question is automotive in nature, so we are at least in the right ballpark here.

We've all heard the expression 'lugging the engine.' What is logging the engine? Well, that's simple. My brother would say this is when you just bought a new engine, like from the junkyard, and you had to lug it home! 

What's commonly known as 'lugging the engine' is driving the vehicle in a higher gear than you need for the speed you're going. For example, if you are driving 25 miles an hour, where you would ordinarily be in the second year, but you are driving in fourth or fifth gear, you would be guilty of lugging the engine.

And if you keep driving like that, you may not have a long-term relationship with your engine! So here's the puzzler question. Why is lugging the engine bad? Why is that true? 

Everyone always says it's bad to lug the engine, but nobody tells you why. So that's the question. Why is it bad to lug the engine?



So, why lugging the engine so bad?

Someone stopped me out in the street the other day and said, "I think I know the answer to the question about lugging. It's bad for the engine because it puts too much of a strain on the engine."

I said, "You don't win the prize for that kind of sloppy answer..." Although that is kind of correct. It does put too much of a strain on the engine, but that isn't what we are looking for.

What's the result of putting too much strain on the engine? 

Lugging the engine is a bad thing because the engine overheats.

And one of the reasons it overheats is because lugging will slow the pistons down. You're making the engine run very, very slow, building a lot of charges. You've got the gas pedal down on the floor. You're sucking in a lot of gasoline and air, creating a big explosion and you're allowing it to stay in the cylinders for too long. And all that trapped heat and energy... it overheats the engine. Instead of doing its work, pushing the piston down and the energy right out the tailpipe, it's all staying in there too long. And it overheats. So there you have it.

Not sure what to do with your old car? Your favorite NPR station can turn it into your favorite NPR radio show. Here's how.


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