Backwards Engine Enigma

May 19, 2018

RAY: This week's puzzler came right out of cyberspace, from a guy named Michael Lydon.

Mike says, "I heard an encore show, and I figured you guys are in bad shape for puzzlers. It sounded so pathetic."

"I cut my mechanic's teeth, so to speak, as a pump jockey at a Sunoco station in the 'burbs of Cleveland." He says in parentheses, "That's the one hint you get."

Mike goes on to say, "We had a guy who helped out holding wrenches, catching oil spills, and holding up cars. His name was Harley. Strong as an ox -- and twice as smart.

"One day a friend came in with a Chevy 350 engine that he had picked up at a junkyard. He wanted to rebuild it and was looking for some pointers. Afterwards he asked one question:

'How do I get the engine to rotate in the other direction?'"

"Harley was stumped, as you might expect. He couldn't help but wonder, 'Why would you want to rebuild an engine so that it ran backwards?'"

And that's today's question: why would you want a Chevy 350 to run backwards?



RAY: Here’s the answer. Think Lake Erie. If you were thinking about boats and you had two inboard engines, you would want one of them to go one way and one to go the other way. Otherwise, the boat would just go around in circles all the time. You want the props to wash in opposite directions.

TOM: So that would really make it go nice and straight ahead.

RAY: I would think so. How do I know? I don't even own a boat. The rumors are all false. I do not own a boat. I have never made a boat payment in my life, so I wouldn't know. It could be bogus. I'm just going on blind faith and it seemed intuitively obvious that you would want the props to go in opposite directions. For symmetrical reasons.

TOM: I think it's bogus.

RAY: And if you had one engine, how would you get that to run backwards and forwards at the same time? Figure that out. 

Get the Car Talk Newsletter