Seized fuel lines and recessed injector nozzles can turn a simple swap into a nightmare. The ATC JT4790 8-Piece Socket Set provides the deep-reach, flare-nut geometry required to break loose stubborn diesel fittings without damage.

The Problem with Standard Sockets on High-Pressure Lines

Modern common-rail and mechanical diesel injectors are often buried beneath rocker housings or tucked behind complex intake plumbing. Using a standard deep socket is impossible because the high-pressure fuel line remains attached during the initial break-loose phase. Conversely, using a standard open-end wrench often results in "rounding off" the soft brass or steel hex nuts due to the limited surface contact. The ATC JT4790 set features a specialized side-window cutout design. This allows the socket to slide over the fuel line and engage the hex nut with the full torque of a 1/2" drive tool, providing a 6-point grip that distributes force evenly across all flats of the fastener.

• Comprehensive 8-Piece Metric Range – Covers all industry-standard sizes for medium and heavy-duty injectors: 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, and 19mm.
• High-Torque 1/2" Drive – Engineered to withstand the breakaway force required for heat-cycled, carbon-bonded nozzle fittings.
• Side-Window Geometry – Precision cutouts allow for easy bypass of fuel return lines and high-pressure rails without disconnecting structural plumbing.
• Thin-Wall Construction – Designed to slip into the narrow injector wells found on modern multi-valve cylinder heads.
• Durable Storage Organization – Supplied in a rugged, blow-molded carry case to keep your inventory organized in high-volume shop environments.

Professional Access for Common-Rail Service

The ATC JT4790 Injector Nozzle Socket Set is an essential addition to any diesel technician’s roll cab. Stop struggling with crowfoot wrenches that slip—get the wrap-around security of a dedicated injector socket.

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