There is an old coin machine at Lefty's toilet. Grab some coins from the table and test it.
This is the low-spoiler guide for "The old coin machine" puzzle in Leisure Suit Larry - Wet Dreams Don't Dry. Unlike in normal walkthrough, you get gradual hints on how to solve the puzzle. Click the big button below to see your first hint. If the hint contains a spoiler, you will be warned about it before clicking.