Slow walking Walter, fire engine guy

The story:

A freind of mine was singing along with smoke on the water in the car and when it got to this line he starts sing ing "Slow walking Walter... Fire engine guy". We all bust out laughing and he couldn't figure it out. When we finally managed to tell him why it was so funny he got really embarassed - then decided his words were better and he still sings it that way... actually, I've gotten so used to it I catch myself singing it his way all the time.