GX PUMP GX-E-CS4-I Portable PCP Air Compressor — 350W, 5800 psi, Built-in 110V/12V Converter

Overview

Meet the GX PUMP GX-E-CS4-I, a portable PCP air compressor engineered for high pressure filling on compact cylinders. Powered by a genuine 350W motor, it uses a four stage compression system paired with a water cooled block to deliver stable performance. At a measured 70 dB, it stays relatively quiet for a device of its class. The built in dual pointer gauge and two level auto stop settings add an extra layer of safety and user control during fills.

Power, cooling, and reliability

The unit features a water tank and a grease tank mounted on top, delivering active cooling and lubrication to support longer operation windows. This layout helps sustain up to five hours of continuous work under favorable conditions. For first use, fill the water tank with neutral distilled water or antifreeze as needed for your climate. Important details include a caution to avoid turning the grease knob before six hours of operation, and the presence of a new hour meter in the latest version to track runtime. A combination of water cooling and cooling fans helps manage heat during high pressure work.

• Five hours of continuous operation with effective cooling
• 15 percent faster filling from 0.5 L to 4500 psi
• Optimized for high pressure small gas cylinders, especially PCP setups

Filling speed and practical expectations

Filling speed varies by tank size. Filling 0.5 L from 3000 psi to 4500 psi typically takes 4–5 minutes, while 0 to 4500 psi takes about 14–16 minutes. A 6.8 L bottle from 0 to 4500 psi may require roughly 2 hours 40 minutes. These figures highlight the CS4 and CS4-I focus on high pressure and compact cylinders rather than large capacity tanks. If you need larger capacity, consider other GX models in the family.

Power options and filtration

The CS4-I variant adds a built in 110 V to 12 V DC converter, enabling operation from a car battery or a household outlet. It also includes an integrated oil water separator. For enhanced filtration performance, GX recommends pairing with a professional external filter when needed.

Setup, safety, and what's included

Before startup, read the user manual carefully. The compressor uses quick connectors: M10x1 and 8 mm female. Dimensions are 11.8 by 6.1 by 12.4 inches, and it weighs about 29 lb. When a fill is complete, close the bottle valve first and then open the bleed valve to release line pressure. Always confirm the target gas cylinder maximum safe pressure to avoid over inflation.

What’s in the box: CS4-I PCP compressor, filling hose, 12 V DC cable, 110 V AC cable, user manual, and accessory bag.