Many user friends are very worried about being cheated in the procurement process of generator sets. They are most afraid of the situation that old equipment is renovated and pretended to be new equipment. According to the experience of some technicians and old engine operators of Haixing power, the old and new degree of the old diesel engine can be identified by the method of one question, two look and three test, focusing on test.

一問：就是詢問柴油機的購置時間、用途及出售原因，修理情況和更換過哪些主要零部件，使用中有些什么問題等，以對該機有個比較的解。

First question: it is to ask about the purchase time, purpose and sales reasons of the diesel engine, the repair situation, which main parts have been replaced, and what problems exist in use, so as to have a more comprehensive understanding of the engine.

二看：就是看該機型是否屬淘汰機型，再從外表看柴油機的新舊程度，后檢查零部件是否齊全，有無損壞。

Second look: first look at whether the model is an obsolete model, then look at the old and new degree of the diesel engine from the appearance, and finally check whether the parts are complete and damaged.

三試：就是試機，柴油發電機組的具體方法是

Third test: test the engine. The specific method of diesel generator set is

1.搖轉曲軸，使噴油泵供油，如噴油嘴發出清脆的噴油聲，說明柱塞副和噴油嘴性能尚好；如齒輪室內無異常聲響，說明齒輪的磨損不嚴重。

1. Rotate the crankshaft to make the fuel injection pump supply oil. If the fuel injection nozzle emits a crisp fuel injection sound, it indicates that the plunger pair and fuel injection nozzle have good performance; If there is no abnormal sound in the gear chamber, the wear of the gear is not serious.

2.上下晃動飛輪，如無響聲、無明顯晃動，說明曲軸主軸頸與軸瓦的間隙不大；轉動飛輪，如無嗒嗒聲，說明曲軸連桿軸頸與連桿瓦之間的磨損不嚴重。

2. Shake the flywheel up and down. If there is no sound or obvious shaking, it indicates that the clearance between crankshaft main journal and bearing bush is not large; Rotate the flywheel, if there is no click, it indicates that the wear between the crankshaft connecting rod journal and connecting rod pad is not serious.

3.使氣缸減壓，搖轉曲軸，當拆除減壓時，如活塞的反彈力大，飛輪迅速回轉，說明氣缸套、活塞、活塞環的磨損水平小。這時機油壓力表讀數應不低于1或機油壓力指示紅色浮標能很快升起，手壓浮標應費力。

3. Depressurize the cylinder and rotate the crankshaft. When removing the depressurization, if the rebound force of the piston is large and the flywheel rotates rapidly, it indicates that the wear level of cylinder liner, piston and piston ring is small. At this time, the reading of the oil pressure gauge shall not be lower than 1 or the red buoy indicating the oil pressure can rise quickly, and the manual pressure buoy shall be laborious.

4.起動柴油機比較容易，排氣無色或淺灰色，轉速穩定，無雜音，則說明柴油機技術狀態良好。

4. If the diesel engine is easy to start, the exhaust is colorless or light gray, the speed is stable and there is no noise, it indicates that the diesel engine is in good technical condition.