(1) Insufficient cylinder compression pressure of mixer engine

造成汽缸壓縮壓力不足的原因主要有：活塞環嚴重磨損（活塞環嚴重磨損將使柴油機嚴重冒藍煙）、壓縮比偏?。ɑ钊旈g隙太大或氣門座圈凹入太深）或氣門密封不嚴等。

The main causes of insufficient cylinder compression pressure are: serious wear of piston ring (serious wear of piston ring will cause serious blue smoke of diesel engine), small compression ratio (piston crown clearance is too large or valve seat ring is too deep) or valve seal is not tight.

ａ、攪拌車活塞頂間隙太大

a. The piston crown clearance of mixer is too large

如果裝配柴油機時，沒有嚴格按照要求檢查并調整活塞頂間隙，或調整不當時活塞頂間隙偏大時，直接影響柴油機的壓縮比進而影響汽缸壓縮壓力。由于壓縮比變小，攪拌車zf減速機降低了汽缸的壓縮壓力和溫度，使燃油燃燒的條件變得更加惡劣，燃油燃燒不完全、不充分，柴油機嚴重冒黑煙。水泥攪拌車

If the piston crown clearance is not checked and adjusted strictly according to the requirements when assembling the diesel engine, or if the piston crown clearance is too large when the adjustment is not made, the compression ratio of the diesel engine will be directly affected, and then the cylinder compression pressure will be affected. As the compression ratio becomes smaller, ZF reducer of mixer reduces the compression pressure and temperature of cylinder, which makes the condition of fuel combustion worse. The fuel combustion is incomplete and insufficient, and the diesel engine emits black smoke seriously. Cement mixer

確?；钊旈g隙的正確是裝配柴油機時必須嚴格做到的重要事件之一。在裝配柴油機時，攪拌車導軌必須將活塞頂間隙調整在技術規范要求的公差范圍內。一般情況下，只要安裝正確，東風大力神攪拌車活塞頂間隙在使用過程中的是不會變化的。攪拌車價格

To ensure the correct clearance of piston crown is one of the important events which must be strictly done when assembling diesel engine. When assembling the diesel engine, the piston crown clearance must be adjusted within the tolerance range required by the technical specification. In general, as long as the installation is correct, the piston crown clearance of Dongfeng Hercules mixer truck will not change in the process of use. Price of mixer truck

ｂ、氣門密封不嚴

b. The valve seal is not tight

氣門密封帶嚴重變形或磨損，將導致氣門密封不嚴，直接降低汽缸壓縮壓力和溫度，使燃油燃燒不完全、不充分，導致柴油機嚴重冒黑煙。水泥攪拌車

Serious deformation or wear of valve sealing belt will lead to valve sealing not tight, directly reduce cylinder compression pressure and temperature, make fuel combustion incomplete and insufficient, and cause serious black smoke of diesel engine. Cement mixer

ｃ、氣門座圈凹入太深

c. The valve seat insert is too deep

氣門座圈長期經受燃燒高溫和氣門的強烈沖擊，加之氣門座圈底孔的鋁合金性質，將使氣門座圈凹入逐步增加， 使氣門平面與缸蓋底面之間的尺寸相對增加，相應增加了燃燒室的容積，降低了柴油機壓縮比，從而降低了汽缸的壓縮壓力和溫度，中聯混凝土攪拌車導致燃油燃燒不完全、不充分，柴油機嚴重冒黑煙

The valve seat insert has been subjected to the high temperature of combustion and the strong impact of the valve for a long time. In addition, the aluminum alloy property of the bottom hole of the valve seat insert will make the concave of the valve seat ring increase gradually, The size between the valve plane and the bottom surface of cylinder head is relatively increased, the volume of combustion chamber is increased correspondingly, the compression ratio of diesel engine is reduced, thus the compression pressure and temperature of cylinder are reduced. The fuel combustion of Zoomlion concrete mixer is incomplete and insufficient, and the diesel engine emits black smoke seriously