Pressure Test
For specifications see " Fig 1 " in appropriate TUNE-UP story.
Some pumps have an internal bleed which lets pressure drop to zero with engine off.
Connect pressure gauge in fuel line at carburetor using a "T" fitting so carburetor will be supplied with fuel. Hose to gauge should have a second "T" and a valve, for venting and capacity test. Crank or run engine at specified RPM and open vent valve to release air in pump. Close vent and read pressure.