Evaporative Emissions System: Testing and Inspection

Fig. 17 Fabricated monometer:

1. If a manometer is not available, one may be fabricated as follows:
a. Attach a 6 foot length of clear plastic tubing (3/8 inch) to a 4 foot 6 inch 1 inch board, Fig. 17.
b. Fill plastic tube with water to a height of 15 inches.
2. Inspect system for any visual defects, such as loose or damaged hoses, clamps, etc., and repair or replace as necessary.
3. Remove fuel return line from fuel filter and plug opening in filter.
4. Remove fuel tank vapor hose from charcoal canister and connect a plastic tube between the hose and manometer. Fuel tank must be no more than 3/4 full.
5. Using a hand air pump, pressurize system at fuel return hose until water in manometer rises 15 inches from no pressure position.
6. Using a soap and water solution, inspect all system connections for leaks and repair as necessary.
7. Connect fuel tank vapor hose to charcoal canister and fuel return line to filter.