4TNV98 & 4TNE98 Diesel Engine Section 4. Fuel System152NOTE: The MP4 fuel injection pumps (4TNV98model engines) are fastened to the gear case withfour (4) studs and nuts.24. Remove the fuel injection pump (Figure 7-17,(1)). For purposes of future injection timingpurposes, record the fuel injection pump timingindex number located on the boss on theengine side (back) of the of the fuel injectionpump (Figure 7-18, (1)).Figure 7-18CAUTIONDo not rotate the crankshaft with the injectionpump removed.25. If the fuel injection pump requires servicing, itmust be sent to an authorized Yanmar FIErepair facility for repair and calibration, orreplaced with a new fuel injection pump.CAUTIONNEVER remove or attempt to remove thetamper-proof devices from the full-load fueladjusting screw or the high-speed throttle limitscrew on the fuel injection pump and governorassembly. These adjustments have been madeat the factory to meet all applicable emissionsregulations and then sealed.NEVER attempt to make any adjustments tothese sealed adjustment screws. If adjustmentsare required, they can be made only by aqualified fuel injection shop that will ensure theinjection pump continues to meet all applicableemissions regulations and then replace thetamper-proof seals.Tampering with or removing these devices mayvoid the “Yanmar Limited Warranty.”Installation of Fuel Injection PumpIMPORTANTIf installing a new or recalibrated fuel injectionpump, locate and record the timing indexnumber located on the pump housing boss onthe engine side of the new or recalibrated fuelinjection pump (Figure 7-19, (1)). This numberwill be used to calculate and adjust the final fuelinjection timing.NOTE: If either or both of the fuel injection pumpsdo not have a timing index number, note theinjection pump ID (example: XK42) on the injectionpump ID label.
