Yanmar 2TNV70 Service Manual

Also see for 2TNV70: Service manual Operation manual Service manual

Contents

FUEL SYSTEM7-4 TNV IDI Service ManualIntroductionINTRODUCTIONFigure 7-1This section of the Service Manual describes theprocedures necessary to remove, install, and timethe ML fuel injection pump and its associatedsystem components. This fuel injection pump isrepresentative of the fuel injection pumps used onother TNV IDI model engines.Fuel Injection PumpNote: If the ML fuel injection pump itselfrequires servicing, it must be taken to anauthorized Yanmar FIE (Fuel InjectionEquipment) repair facility.The following describes the features of the ML fuelinjection pump, manufactured by Yanmar.The fuel injection pump is a very importantcomponent of the engine. It is capable of makingvery precise fuel delivery adjustments according tothe varied loads applied to the engine.All of the fuel injection pump components are veryprecisely machined. It is extremely important tofollow good service practices and maintaincleanliness when servicing the fuel injection pump.The Yanmar ML Fuel Injection Pump is an in-linetype pump which consists of a fuel supply plunger(Figure 7-1, (1)) for each cylinder, a camshaft(Figure 7-1, (2)), and a pump housing(Figure 7-1, (3)). A delivery valve (Figure 7-1, (4))connects to a high-pressure fuel line for eachcylinder. The fuel injection pump housing containsa governor (Figure 7-1, (5)).Fuel from the fuel tank to the fuel injection pump isdelivered by a low-pressure electric fuel pump. Ona few special models, a mechanical fuel pump isused instead of an electric pump. The mechanicalfuel pump is mounted to the fuel injection pumphousing in place of the cover plate(Figure 7-1, (6)).Fuel to be injected into the cylinders is pressurizedby the up and down motion of eachcamshaft-driven plunger, and is then supplied bythe high-pressure fuel lines to the respective fuelinjector.(4)(1)(3)(5) (6)(2)0002238