Part of the Yanmar Repair Manuals.
Set an MP pump on the bench with the governor housing off and you are looking at a plunger, a control rack and a governor weight assembly that all have to go back together in one exact order. This Yanmar service manual, publication M9961-03E070, works that order in both directions for the YPD-MP2 and YPD-MP4 series fuel injection pumps, models YPD-3MP2, YPD-4MP2 and YPD-4MP4, fitted to Yanmar TNV diesel engines.
Across 66 pages it covers pump construction and specifications, full disassembly and reassembly of the hydraulic head, camshaft and governor, bottom clearance adjustment for injection timing, and fuel injection nozzle service from washing through pop pressure setting. Symptom-based troubleshooting tables and a tightening torque chart for the pump and mechanical governor close it out.
It is a bookmarked English PDF that reads well on a laptop beside the test stand and prints cleanly for the bench.
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| For Safe Servicing | 6-8 | Warning Symbols, Safety Precautions |
| General Information | 9-26 | Mp Pump, Specifications, Fuel Injection Pump, MP-Pump (Fuel Injection Part, Governor Part, Delivery Part) |
| Disassembly, Reassembly and Inspection | 27-46 | Disassembly (Separating the Pump Body From the Governor Body, Separating the Governor Weight Cmp, Disassembling the Hydraulic Head, Separating Hydraulic Head Cmp, Separating the Cam Shaft, Disassembling the Hydraulic Head Cmp) |
| Adjustment of Fuel Injection Pump and Governor | 47-53 | Preparations, Bottom Clearance Adjustment (Bottom Clearance Adjusting Value and Cam Classification) |
| Fuel Injection Nozzle | 54-59 | Functioning of Fuel Injection Nozzle, Type/Construction of Fuel Injection Nozzle, Fuel Injection Nozzle Disassembly, Fuel Injection Nozzle Inspection (Washing) |
| Troubleshooting | 60-62 | Troubleshooting of Fuel Injection Pump, Major Faults and Troubleshooting |
| Tightening Torques for Main Bolts and Nuts | 63-64 | Pump Part, Mechanical Governor Part |
| Tools | 65-66 | Nozzle Plate, Bottom Clearance Gauge, Plunger Sp Seat Extractor |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Pipe joint bolt, fuel inlet torque | 25-29 N-m | p. 63 |
| Plug, barrel torque | 50-55 N-m | p. 63 |
| Feed pump assembly replacement interval | 10,000 hours | p. 23 |
| Wear limit for pump case, pump cover, inner rotor, outer rotor | 0.1mm | p. 24 |
| Delivery holder torque | 40-45 N-m | p. 42 |
| Molded ring replacement | replace | p. 24 |
| Seal washer replacement | replace | p. 24 |
| Governor case packing (GRC) reusability | not reusable | p. 45 |
| Trochoid pump replacement interval | 10,000 hours | p. 23 |
| Wear limit for shaft and oil seal moving area | 0.05mm in depth | p. 24 |
| Tension lever side clearance | 0.3 to 0.6 mm | p. 44 |
| Fixing bolt, tension lever hook torque | 6-8 N-m | p. 64 |
