N.J. Phillips major service kit w/ barrel for automatic metal injector

Details

Metal injectors do not usually die, they just get vague. The dose creeps, a drip appears at the nose between shots, and the lever feels different than it did last year. All of that traces back to the same handful of soft parts and, eventually, to the cylinder they run against. This is the major kit, which means it carries a replacement cylinder in addition to the wear items: head seal washer, inlet valve washer, delivery valve washer, cup support washer and piston seal ring. That is the full set of what wears in these guns, so fitting it puts the instrument back where it started mechanically. The distinction that matters at the counter is major versus minor. If the cylinder bore is still clean and the problem is only seepage or a soft-feeling stroke, the minor kit covers the washers and seals with less disturbance. Choose the major kit when the bore is scored, pitted or has been run dry, because no amount of new sealing will fix a damaged cylinder. Kits are matched to a specific injector model and capacity, and the metal injector range spans several sizes that do not share parts. Confirm the model number stamped on your gun before ordering. Once rebuilt, wash it out after every use and lubricate the seal and moving parts before it goes away.