A compact, highly portable, multi-mode
fluid injection system able to reach difficult to access places to efficiently service a variety of
diameter pipes, tubing and related components. The
system comprises a tank having a first port which allows access to the tank's upper contents and a second port which allows access to the tank's lower contents, a means for introducing liquid into the tank, a
hand pump built into the tank to pressurize the tank and its contents, one or more applicators, and flexible hoses which connect the applicators to the first and / or second port to supply the applicators with the tank's contents. The
system is capable of producing, alternatively, pressurized liquid or gas without an independently powered
air compressor or consumable gas cartridges, and without having to empty and / or fill the tank. An onboard means for stowing the hose conduits, an injection gun applicator having a small travel-high flow valve with adjustable accumulation chamber, and applicators having stiff-flexible tips and tip extensions are also described.