A mechanic was removing a cylinder head
from the engine of a class A motorhome when he spotted a well-known heart
surgeon in his shop.
The surgeon was there waiting for the service manager to
come take a look at his RV when the mechanic shouted across the garage,
"Hey, Doc, can I ask you a question?"
The surgeon, a bit surprised,
walked over to the mechanic, who straightened up, wiped his hands on a rag and
asked,
"So Doc, look at this engine. I open its heart, take the valves
out, repair any damage, and then put them back in, and when I finish it works
just like new. So how come I'm paid so little compared to you when we're doing
basically the same work? 
The surgeon paused, smiled and leaned over and
whispered to the mechanic, "Try doing it with the engine running."
