rid your gauge of air bubbles
on November 16, 2008
Hi.. I too have a Motion Pro manometer (an Hg type) and have experienced these little bubbles. .they're either air or suspended gasoline that condense from vapor introduction.
purge the tubes with air until the fluid and air bubbles are gone from the metering tubes. this is basically like resetting them. they'll never migrate out of the tubes due to specific gravity and surface tension, but will once moved to the fluid tank.
whether you chose to blow into the rubber line or use a VERY low (in both pressure and flow) compressed air burst, is up to you.