Komatsu S4D84E, S4D98E & S4D106 Engine Repair Manual PDF

Manuals: Shop Manual
1. General …………………………………………………………………………………………. 1
2. Inspection and Adjustment……………………………………………………………… 22
3. TROUBLESHOOTING…………………………………………………………………… 53
4. Disassembly, Inspection and Reassembly of Engines………………………… 59
5. LUBRICATION SYSTEM ……………………………………………………………… 108
6. COOLING SYSTEM………………………………………………………………………112
7. FUEL INJECTION PUMP/GOVERNOR……………………………………………114
8. TURBOCHAGER: Disassembly, inspection and reassembly…………………118
9. STARTING MOTOR…………………………………………………………………….. 140
10. ALTERNATOR…………………………………………………………………………… 176
11. ELECTRIC WIRING …………………………………………………………………… 180
12. SERVICE STANDARDS …………………………………………………………….. 185
13. TIGHTENING TORQUE for BOLTS and NUTS ……………………………… 196
Fuel injection pump is the most important equipment, which is enable to make the sensitive adjustment according to the variable load of the engine.
Therefore all of the parts are required not only very precise machining but also finest, assembling with top level.
The careful arrangement of keeping off the dust and the rust when disassemble, adjustment and
reassemble of the fuel injection pump is made in the market.

YDP-MP Pump is a distributor type pump which is unified of Mono-plunger, a distributing shaft, a hydraulic head which equipped the delivery valve for each cylinder, pump housing which has a cam shaft internally and governor.

The fuel, which is pressurized by the up and down movement of the plunger driven by the cam-rotation, is supplied through the distributor shaft, which is rotating accordingly.
There are a model YDP-MP2 and a model YDP-MP4, and plunger diameter and fuel cam speed are different.