英国珀金斯柴油机不能起动的几种原因分析
英国珀金斯柴油机正常运转的先决条件是雾化良好的柴油能准确及时地喷入燃烧室内，并且燃烧室里的压缩空气要达到足够的温度才能着火、爆发。要满足这两个条件，就必须在柴油机起动时有足够高的转速和使气缸内有一定的温度。柴油机不能起动时，应从起动工作、柴油机燃油供给系统和压缩等方面寻找原因。

(1)环境温度太低。在气温低的情况下，应做好英国珀金斯柴油机的预热工作，否则不易起动。
(2)起动转速低。对于手摇起动的柴油机来说，应逐渐加大转速，然后将减压手柄扳到非减压位置，使气缸内有正常的压缩。如果减压机构调整不当或是气门顶住了活塞，往往会感到摇车很费力。其特点是曲轴转到某一部位就转不动了，但能退回来。此时，除了检查减压机构外，还应查看正时齿轮啮合关系是否错了。而对于使用电起动机的柴油机，如果起动转速极其缓慢，大多系起动机无力，并不说明柴油机本身有故障。应对电器线路方面进行详细检查，判断蓄电池是否充足电，各导线连接是否紧固及起动机工作是否正常。

从珀金斯发动机排气的颜色判断发动机的技术状态
英国珀金斯发动机工作时，燃料在气缸内燃烧后生成废气排出机外。当发动机工作正常和燃料完全燃烧时，废气中主要有水蒸气（H2O）、二氧化碳（CO2）和氮气（N2），废气一般呈浅灰色。当燃料不完全燃烧或发动机工作不正常时，废气中还会有碳氢化合物（HC）、一氧化碳（CO）、氮氧化合物（NOx）和碳粒等有害物质存在，使废气的颜色呈现白色、黑色或蓝色。可见，发动机排气的颜色能反映燃料燃烧状况和发动机技术状态。因此，汽车驾驶员和汽车维修人员可以通过发动机排气的颜色判断发动机的技术状态。

一、 英国珀金斯排气冒黑烟
排气中的黑烟主要是燃料不完全燃烧的碳粒。因此，燃油供给系统燃料的过量供给，进气系统空气量减少，缸体、缸盖与活塞构成的燃烧室的密封性差，喷油器喷射质量差等因素都会使燃料燃烧不完全，从而使排气冒黑烟。排气冒黑烟主要有以下原因：
1．高压油泵供油量过大或各缸供油量不均匀
2．气门密封不严，造成漏气，气缸压缩压力低
3．空气滤清器进气道阻塞、进气阻力大，使进气量不足

4．缸套、活塞、活塞环严重磨损
5．喷油器工作不良
6．发动机超负荷运转
7．喷油泵供油提前角过小，燃烧过程后移到排气过程进行
8．汽油电喷系统控制失效故障等
对于冒黑烟的发动机可通过高压油泵调校，喷油器喷射试验检查，气缸压缩压力测量，进气道清洁，供油提前角的调整、汽油电喷系统故障诊断等工作予以检查和排除。

二、 英国珀金斯排气冒白烟
排气中的白烟主要是未充分雾化和燃烧的燃油颗粒或水汽，因此，凡是导致燃油无法雾化或水进入气缸内都会使排气冒白烟。归纳主要有以下原因：
1．气温低且气缸压力不足，燃油雾化不好，特别是冷起动初期排气冒白烟
2．缸垫损坏，冷却水渗入气缸内
3．缸体裂，冷却水渗入气缸内
4．燃油中含水量大等
冷起动时排气冒白烟，发动机暖机后白烟消失应视为正常，若车辆正常运行时仍冒白烟则为故障，应通过观察水箱内冷却水是否不正常消耗，各缸工作是否正常，油水分离器是否水量过多等进行检查和分析，排除故障部位

三、排气冒蓝烟
排气中的蓝烟主要是机油过量窜入燃烧室参与燃烧的结果。因此，凡是导致机油窜入燃烧室的原因都会使排气冒蓝烟。归纳主要有以下原因：
1．活塞环断
2．油环上回油孔被积碳堵塞，失去刮油作用
3．活塞环开口转到一起，造成机油从活塞环开口上窜
4．活塞环磨损严重或被积碳卡滞在环槽内，失去密封作用
5．气环上下方向装反，把机油刮入气缸内烧掉
6．活塞环弹力不够，质量不合格
7．气门导管油封装配不当或老化失效、失去密封作用
8．活塞、缸筒严重磨损
9. 机油加入量过多，使机油飞溅过多，油环来不及刮下缸壁多余的机油等
排气冒蓝烟必然伴遂幡巍怼啤笑桅痞兀油消耗增多，有的驾驶员称“烧机油”。机油、燃油消耗比一般为0．5%～0。8%，机油消耗超过此值时排气中将有蓝烟产生。发动机冒蓝烟的故障，一般要通过发动机解体、检查，才能找出原因并确定排除故障的方案。冷机状态排烟发蓝，但机油消耗正常的，与燃料有关，视为正常。
发动机排烟一般应在发动机暖机状态时检查，通过发动机低速、中速、高速及加速过程中排烟颜色的变化进行分析

Piston damage phenomena are: 1: piston top surface ablation. The 2: piston ring groove side wall wear and ring fracture. 3: piston pin hole aperture greatens, out of round. The 4: pin base crack. 5: piston initial strain. 6: early wear and horse ellipse piston. The 7: piston ring groove medial ridge peak exists. 8: piston wear too large.

C. connecting rod assembly

Connecting rod assembly of major injury are: 1: head liner wear. 2: small end bushing seat hole and the big end bearing saddle bore wear and deformation. 3: rod bending distortion. Connecting rod bolt or screw4: crack, variable length, thread wear or slipping buckles. 5: connecting rod body scratch phenomenon. 6: connecting rod has a tile deformation phenomenon. In the installation of connecting rod assembly, must press the correct torque parameters and the correct procedure, and must be inspected for screw screw.

Warning: installing a linkage assembly, shall be determined by the project manager to operate personally. For the damage of connecting rod assembly, must be scrapped, otherwise it will cause the connecting rod fracture, break the cylinder block, crankshaft and the risk of break.

Crankshaft, flywheel assembly: D. from the axis of the main shaft neck injury: abrasion, crack and fracture, burning tile resulting ablation. If the crankshaft out of roundness is greater than 0.05mm, will be grinding crankshaft. For tile serious crankshaft, due to its metallographic structure has changed, is generally not recommended to use again, crack phenomenon of the crankshaft must be scrapped, or there will be the possible fracture.

Warning: installing crankshaft, flywheel assembly, shall be determined by the project director in person operation, according to the criteria of the torque and the correct steps, main bearing cover screws must recheck.

E. cylinder cover and a gas distribution mechanism,1, cylinder head and cylinder cover and the cylinder body joint plane, valve guide hole, the valve seat hole, the injector hole, water cooling wall, easy to crack, available visual inspection, pressure test check. The cylinder cover and the cylinder body joint planes are not usually, advice on grinding machine repair, each processing capacity of around 0.10mm, processing limit is 1.00mm. The injector cylinder leakage or damage will cause the water leakage, deal with the fuel injector copper sets to be renewed. Cracked cylinder head suggested to be scrapped, otherwise it will cause the water leakage phenomenon. 2, gas distribution mechanism:1) the valve seat and the valve guide / individual units of the valve seat and the valve guide should be grinding, grinding amount must be correctly, otherwise it will cause impact piston valve, valve and valve catheter blocked, oil consumption increases fault. This work is required by the project director personally operation .2) valve spring / check valve spring length and elastic, soft spring will result in valve beating, the valve and valve seat exacerbates wear, will also destroy the valve timing, valve and piston collisions. Unqualified spring must be scrapped. 3) valve and valve seat ring polishing / grinding paste grind the valve, the valve and valve seat ring a linear contact, all valve grinding is finished, must be grinding paste clean (with particular attention to the valve catheter within the grinding paste clean ). 4) valve upper cover and a lower cover / check have no crack, failure will be scrapped. 5) the camshaft / check camshaft type cam shaft neck area of any crack, dent, corrosion, abrasion, check the gear has no cracks, tooth fracture or tooth surface pits, unqualified will be scrapped, otherwise it will cause a black smoke, power loss, the risk of breaking cylinder. 6) the cam follower / check the driven shaft and not exceed the standard, unqualified will be scrapped. Check the wheel surface is pitted, rotation is flexible, whether the excessive wear and tear, unqualified will be scrapped. Check the wheel pin and a pin hole is worn, exceed the standard will be scrapped. Check with the boom has no cracks, such as there is to be scrapped. 7) valve and fuel injector push rod / ball end without excessive wear and tear, the push rod is losing a round, there is no bending, unqualified then will be scrapped. 8) an arm / check for cracks, and the T-shaped plate contact convex are worn or damaged, rocker arm bushing diameter not exceed the standard. Check the arm shaft wear, exceed the standard criterion. Be scrapped9) T-shaped plate / check T-shaped plate aperture having no exceed the standard, the T-shaped plate thread for wear and damage, as qualified will be scrapped.

Warning: the cam follower is the key and difficult parts, need to be special examination, otherwise there will be a black smoke, power loss, breaking cylinder crankshaft risk.

F. intake system

1. Turbocharger main damage reasons: 1) lack of oil or fuel lag. 2) external debris or sediment into the lubrication system. 3) lubricating oil oxidation or deterioration. 4) foreign body into the engine intake or exhaust system. Turbocharger repair1) on the front, the air compressor casing, the turbine casing and bearing shells for mark, contribute to the assembly when the alignment. 2) the supercharger dissolution. 3) check the parts, air compressor shell, turbine shell, shell bearing has no cracks or deformation, failure will be scrapped. Air compressor impeller and turbine exhaust impeller if there is crack, fracture and touch of scratch marks, to be scrapped. Exhaust turbine shaft seal ring groove does not allow deep grooves, otherwise it will cause a supercharger burning oil. 4) assembly / change the new bearings, thrust pad circle, an oil retaining ring, O ring. The assembly line, with feeler gauge check turbocharger compressor end at one end and a radial clearance. 2. Intercooler / cooler working lose thesuburb will lead to engine power loss, the black smoke, the cooler should be clean, in general we recommend using the days that water cleaning.

G. fuel supply system,1. Pump / pump test bench for detecting and regulating, replacing the bad parts, for Cummings PT pump, but also to the electronic actuator leakage test, if the electronic actuator wear is excessive, leakage amount exceed the standard, will cause the engine speed instability, hot cars have runaway phenomenon, should be the electronic actuator to be renewed, check the fuel cut-off valve is working properly, will lead to loss of suburban stopping fuel is not tightly closed to stop, lose thesuburb main components are the coil of the solenoid valve, a sealing gasket and a spring sheet, check whether the loss of speed regulating system of rural. For high pressure oil pump plunger, check whether excessive wear and tear, spring is lose thesuburb, speed control system whether lose thesuburb, oil pump is not working properly can cause power loss, black smoke, speed instability failure2. Injector / injector test stand for inspection training, change adverse element, the fuel injector is lose thesuburb, causes the power loss, the black smoke, the oil pan of diesel fault.

Warning : pump, fuel injector is the heart of diesel engine parts, must be sent to live have professional equipment and skills of pump pen company repair, diesel engine overhaul must belong to the maintenance project.

H. lubrication system,1. Oil / at present, fake oil filling market, we recommend that users buy oil do not covet petty gain, and should to the oil producers owned subsidiary or size of the supplier, use of fake oil, will lead to mechanical wear intensifies, liner burnt, damage, or even scrapped machine crankshaft. 2. Oil pump / pump overhaul must be carried out for inspection, inspection items are as follows: 1) the driving shaft, the driven shaft and a pump body positioning pin is worn and damaged. 2) check the pump body, cover has no cracks and damage, the pump body of the threaded bushing damage. 3) a variety of inner bore of the bushing, exceed the scope should be replaced. 4) check the main, the driven gear has no cavitation pits, cracks, etc. 5) check the main drive gear has no cracks and other injuries. 6) gear and the pump body clearance shall not be greater than 0.30mm,3oil cooler core / clean diesel to be cleaned, and properly keep the good, so as to avoid damage, the installation must be in the correct program execution, otherwise it will cause the water and oil of mutual infiltration.

Warning: oil pump belongs to the diesel engine 's most dangerous parts, work lose thesuburb will lead to the diesel engine appears devastating consequences, maintenance must check all bushings, gears, drive shaft, exceed the standard must be renewed!

J. cooling system 1pump / overhaul must remove water pump inspection, general situation and ask, we propose to make preventive maintenance. Pump failures, will present the following problems. 1) diesel engine high water temperature, low oil pressure. 2) diesel engine cylinder, tile burning phenomenon appears, even block scrap. 2. Thermostat / if diesel engines have high temperature phenomenon, in check, the thermostat opening and closing temperature is normal. 3. Fan / fan shaft, fan drum without excessive wear and tear and damage, failure will be scrapped. Check the pulley bearings are blocked or damaged, when assembling bearing end gap of 0.08 to 0.41mm. Exceed the standard needed for bearings.

Warning: all the bearings are required to fill the butter!

K. accessory drive / for Cummins PT pump models, overhaul to be on the PT pump driver related bushing. For V type structure of the diesel engine, a gear type bridge transmission gear must be special inspection, the gear as a result of one of the screws is fastened on the cylinder body, long time working gear bushing wear, work gear deflection, not timely maintenance will be sweeping teeth, the gear box smash to the destroyed phenomenon.

Warning: the maintenance of a gear of the gear box assembly, must by the director of engineering of new self operation, ensure that every member of the correct pass before the assembly, each gear screw, gear, are in the correct torque and marking state assembly, the assembly line, must be a comprehensive inspection, certainty before installation of the gear chamber cover. Component assembly incorrect unqualified, will lead to the diesel engine appears devastating consequences!

L. electrical control parts, generator parts: to run for more than 10000 hours of power unit, electric ball coil due to dust and leading to poor cooling, interturn insulation level decreasing, prone to electric ball burnt phenomenon, we suggest to electric ball portion to conduct a c, omprehensive inspection, the project includes:1) electricity ball rotor core processing;2) coil to dust;3) electricity ball bearing, bearing, bearing seat for maintenance, replacement bearing;4) coil impregnation processing;5) coil in the thermostatic oven for baking process;6) using a shake table testing coil to earth insulation level.

A diesel engine can not start several reasons analysis

The normal operation of the diesel engine is a prerequisite for well atomized diesel accurately sprayed into the combustion chamber, and the combustion chamber to the compressed air at a sufficient temperature to ignition, explosion. To meet the two conditions, must be in the starting of the diesel engine with sufficient speed and make the inner cylinder has a certain temperature. A diesel engine can not start, should start working, the fuel supply system of diesel engine and compression, looking for the cause.

(1) the environmental temperature is too low. In the low temperature condition, should do well the work of diesel engine preheating, otherwise not easily starting.

(2) the starting speed low. For the hand starting diesel engine, we should gradually increase the speed, and then decompression handle into non decompression position, so that the cylinder is normal compression. If the relief agency improper adjustments or valve to the piston, often feel hard to shake the car. Its characteristic is the crankshaft to a site is not to move, but can come back. At this time, in addition to check the decompression mechanism, should also check the timing gear in meshing relationship is wrong. And for the use of an electric starter of diesel engine, if the starting speed is very slow, most of the Department of motor weakness, does not describe the diesel engine fault. Electrical wiring should conduct a detailed examination, judgment whether the battery is fully charged, the wire connection is fastened and the starter works whether normally.

Exhaust from the engine to the judgement of color engine technical state

When the engine works, the fuel in the cylinder combustion generated exhaust gas discharge machine. When the engine works normally and the complete combustion of fuel, exhaust gas are mainly water vapor ( H2O ), carbon dioxide ( CO2) and nitrogen ( N2), exhaust gas is generally light gray. When the incomplete combustion of the fuel or the engine does not work normal, ly, gas will be hydrocarbons ( HC ), carbon monoxide ( CO ), nitrogen oxide ( NOx ) and carbon particles and other harmful substances, so that the exhaust gas of the colors white, black or blue. Visible, the engi, ne exhaust color can reflect the status of burning of fuel and engine technical state. Therefore, the driver and vehicle maintenance and repair personnel can pass through the engine exhaust color judgment engine technical state.

One, black smoke exhaust

Exhaust smoke is mainly of incomplete combustion of carbon particle. Thus, fuel supply system and fuel intake system excess supply, air is reduced, cylinder, cylinder head and piston combustion chamber of poor sealing performance, fuel injector of poor quality and other factors will make the incomplete fuel combustion, thereby allowing the black smoke exhaust. Black smoke exhaust mainly for the following reasons:

1 high pressure fuel supply is too large or the cylinder oil quantity is not uniform

2 valve Mifengbuyan, resulting in leakage, the cylinder compression pressure low

The 3 air cleaner inlet obstruction, air resistance, the lack of gas

4cylinder, piston, piston ring wear

A 5fuel injector is bad

The 6 engine overload

The 7fuel injection pump fuel supply advance angle is too small, the combustion process after moved to the exhaust process