X6170ZC series and 8170ZC series marine diesel engines are 6-cylinder and 8-cylinder diesel engines that improved on the basis of the original 170Z series diesel engine. By selecting more advanced turbocharger, high-pressure injection pump, injector, intake pipe and combustion chamber, the engines possess advantages of wide power range, low fuel consumption, low emission and rapid starting. Meanwhile, the cylinder block, cylinder liner, exhaust pipe and oil sump are all been improved, and the engines are more reliable, more advanced, with operation and maintenance more convenient. The power range is from 258kW to 601kW, rotation speed range is from 1000rpm to 1500rpm. The engines can widely be used in various shipping. Structure Advantages of Marine Diesel Engine 1. Gantry structure with the reasonably collocated reinforcing steel bars makes the engine a compact structure with high intensity, high rigidity and low vibration. 2. One cover per cylinder, dual intake pipes and four valves per cylinder can supply enough air intake and optimal intake whirlpool. One cover per cylinder makes it easy for maintenance work. 3. The crankshaft is made of cast iron with high intensity and has been nitrified. It is collocated with 12 weight counterbalances itself which has greatly lessened the load of the main bearing. 4. The connecting rod is forged by alloy steel which makes it much more reliable. 5. The wet cylinder sleeve is cast by alloy of chrome, molybdenum, copper and nickel. Piston is cooled by injection oil. So the cylinder has little abrasion and can supply longevity service. 6. Both P9 high pressure oil pump produced with introduced technology and the imported low inertia injector has super performance and can work with high reliability. 7. Electric motor and air motor can both be supplied according to the end of the customers. Engines equipped with both starting device can also be supplied. Fuel system 1. P9 high pressure oil pump: Tthe P9 high pressure is produced with the introduced technology. It possesses the high reliability and good performance. 2. Improved low inertia injector: High reliability, steady performance and good atomization quality. 3. Electric-magnetism value: It is used for monitoring parameters, and will automatically shut down at emergency. Cooling system 1. Heat exchanger: Improving the cooling condition of diesel engine. 2. Inter-cooler: Lower the intake temperature, and improve the engine performance. 3. Water sleeve exhaust pipe: Lower the temperature in the cabin. 4. Heat seclusion cover: Dry exhaust pipe and the heat seclusion cover with porcelain composite under layer. It can lower temperature inside the cabin and enhance the safety. Performance Advantages of Marine Diesel Engine Broad output range: Its output ranges from 258—601kW. It has a large power storage, high ship speed and quick speed-up ability. Low fuel consumption: the lowest fuel consumption is 197g/kW.h. The engine possesses an even fuel consumption performance curve, and has good economic capability under normal work condition. Low oil consumption: The oil consumption is up to 1.0g/kW.h. Under normal work condition the oil should be replaced every 1500h. Low smoke density and low noise: At standard work condition the smoke density is lower than 1—1.5Rb, and the average noise is lower than 116dB(A).