* Larger diameter lines: From the tank to the fuel pump. This is usually around 5/16" (8mm) inside diameter.
* Smaller diameter lines: From the fuel pump to the fuel injectors. This is typically around 3/16" (5mm) inside diameter.
You cannot rely on this information for repair. To determine the precise size needed for your specific repair, you must measure the existing fuel line directly. Or, consult a repair manual specific to your 1995 Mercury Villager's engine (e.g., a Haynes or Chilton manual) which will have diagrams and specifications. Using the wrong size fuel line could be dangerous and lead to fuel leaks.