Yanmar Fuel Injector Replacement Tutorial

This tutorial shows the basic steps for replacing the fuel injectors and fuel pump on a Yanmar 3TNV86CT.

• To determine if the injectors are working properly, use the glass test tubes to monitor the return flow. If the fuel collected in the tubes is not within 10-16 mL after the engine idles for 60 seconds, it is likely that there is an injector problem.
• When replacing the injectors, be sure that the sealing washer and the rubber O-ring stay in place. Be sure the area around the injectors is clean to keep dirt from getting into the engine.
• Torque the injector hold-down clamps to 25 Nm.
• Torque the injection lines to 22 Nm.
• When replacing the fuel pump, align the key on the pump with the keyway in the gear.
• Torque the gear nut to 85 Nm.