英國珀金斯柴油機(jī)不能起動的幾種原因分析
英國珀金斯柴油機(jī)正常運轉(zhuǎn)的先決條件是霧化良好的柴油能準(zhǔn)確及時地噴入燃燒室內(nèi),并且燃燒室里的壓縮空氣要達(dá)到足夠的溫度才能著火、爆發(fā)。要滿足這兩個條件,就必須在柴油機(jī)起動時有足夠高的轉(zhuǎn)速和使氣缸內(nèi)有一定的溫度。柴油機(jī)不能起動時,應(yīng)從起動工作、柴油機(jī)燃油供給系統(tǒng)和壓縮等方面尋找原因。
(1)環(huán)境溫度太低。在氣溫低的情況下,應(yīng)做好英國珀金斯柴油機(jī)的預(yù)熱工作,否則不易起動。
(2)起動轉(zhuǎn)速低。對于手搖起動的柴油機(jī)來說,應(yīng)逐漸加大轉(zhuǎn)速,然后將減壓手柄扳到非減壓位置,使氣缸內(nèi)有正常的壓縮。如果減壓機(jī)構(gòu)調(diào)整不當(dāng)或是氣門頂住了活塞,往往會感到搖車很費力。其特點是曲軸轉(zhuǎn)到某一部位就轉(zhuǎn)不動了,但能退回來。此時,除了檢查減壓機(jī)構(gòu)外,還應(yīng)查看正時齒輪嚙合關(guān)系是否錯了。而對于使用電起動機(jī)的柴油機(jī),如果起動轉(zhuǎn)速極其緩慢,大多系起動機(jī)無力,并不說明柴油機(jī)本身有故障。應(yīng)對電器線路方面進(jìn)行詳細(xì)檢查,判斷蓄電池是否充足電,各導(dǎo)線連接是否緊固及起動機(jī)工作是否正常。
從珀金斯發(fā)動機(jī)排氣的顏色判斷發(fā)動機(jī)的技術(shù)狀態(tài)
英國珀金斯發(fā)動機(jī)工作時,燃料在氣缸內(nèi)燃燒后生成廢氣排出機(jī)外。當(dāng)發(fā)動機(jī)工作正常和燃料完全燃燒時,廢氣中主要有水蒸氣(H2O)、二氧化碳(CO2)和氮氣(N2),廢氣一般呈淺灰色。當(dāng)燃料不完全燃燒或發(fā)動機(jī)工作不正常時,廢氣中還會有碳?xì)浠衔铮℉C)、一氧化碳(CO)、氮氧化合物(NOx)和碳粒等有害物質(zhì)存在,使廢氣的顏色呈現(xiàn)白色、黑色或藍(lán)色??梢?,發(fā)動機(jī)排氣的顏色能反映燃料燃燒狀況和發(fā)動機(jī)技術(shù)狀態(tài)。因此,汽車駕駛員和汽車維修人員可以通過發(fā)動機(jī)排氣的顏色判斷發(fā)動機(jī)的技術(shù)狀態(tài)。
一、 英國珀金斯排氣冒黑煙
排氣中的黑煙主要是燃料不完全燃燒的碳粒。因此,燃油供給系統(tǒng)燃料的過量供給,進(jìn)氣系統(tǒng)空氣量減少,缸體、缸蓋與活塞構(gòu)成的燃燒室的密封性差,噴油器噴射質(zhì)量差等因素都會使燃料燃燒不完全,從而使排氣冒黑煙。排氣冒黑煙主要有以下原因:
1.高壓油泵供油量過大或各缸供油量不均勻
2.氣門密封不嚴(yán),造成漏氣,氣缸壓縮壓力低
3.空氣濾清器進(jìn)氣道阻塞、進(jìn)氣阻力大,使進(jìn)氣量不足
4.缸套、活塞、活塞環(huán)嚴(yán)重磨損
5.噴油器工作不良
6.發(fā)動機(jī)超負(fù)荷運轉(zhuǎn)
7.噴油泵供油提前角過小,燃燒過程后移到排氣過程進(jìn)行
8.汽油電噴系統(tǒng)控制失效故障等
對于冒黑煙的發(fā)動機(jī)可通過高壓油泵調(diào)校,噴油器噴射試驗檢查,氣缸壓縮壓力測量,進(jìn)氣道清潔,供油提前角的調(diào)整、汽油電噴系統(tǒng)故障診斷等工作予以檢查和排除。
二、 英國珀金斯排氣冒白煙
排氣中的白煙主要是未充分霧化和燃燒的燃油顆粒或水汽,因此,凡是導(dǎo)致燃油無法霧化或水進(jìn)入氣缸內(nèi)都會使排氣冒白煙。歸納主要有以下原因:
1.氣溫低且氣缸壓力不足,燃油霧化不好,特別是冷起動初期排氣冒白煙
2.缸墊損壞,冷卻水滲入氣缸內(nèi)
3.缸體裂,冷卻水滲入氣缸內(nèi)
4.燃油中含水量大等
冷起動時排氣冒白煙,發(fā)動機(jī)暖機(jī)后白煙消失應(yīng)視為正常,若車輛正常運行時仍冒白煙則為故障,應(yīng)通過觀察水箱內(nèi)冷卻水是否不正常消耗,各缸工作是否正常,油水分離器是否水量過多等進(jìn)行檢查和分析,排除故障部位
三、排氣冒藍(lán)煙
排氣中的藍(lán)煙主要是機(jī)油過量竄入燃燒室參與燃燒的結(jié)果。因此,凡是導(dǎo)致機(jī)油竄入燃燒室的原因都會使排氣冒藍(lán)煙。歸納主要有以下原因:
1.活塞環(huán)斷
2.油環(huán)上回油孔被積碳堵塞,失去刮油作用
3.活塞環(huán)開口轉(zhuǎn)到一起,造成機(jī)油從活塞環(huán)開口上竄
4.活塞環(huán)磨損嚴(yán)重或被積碳卡滯在環(huán)槽內(nèi),失去密封作用
5.氣環(huán)上下方向裝反,把機(jī)油刮入氣缸內(nèi)燒掉
6.活塞環(huán)彈力不夠,質(zhì)量不合格
7.氣門導(dǎo)管油封裝配不當(dāng)或老化失效、失去密封作用
8.活塞、缸筒嚴(yán)重磨損
9. 機(jī)油加入量過多,使機(jī)油飛濺過多,油環(huán)來不及刮下缸壁多余的機(jī)油等
排氣冒藍(lán)煙必然伴遂幡巍懟啤笑桅痞兀油消耗增多,有的駕駛員稱“燒機(jī)油”。機(jī)油、燃油消耗比一般為0.5%~0。8%,機(jī)油消耗超過此值時排氣中將有藍(lán)煙產(chǎn)生。發(fā)動機(jī)冒藍(lán)煙的故障,一般要通過發(fā)動機(jī)解體、檢查,才能找出原因并確定排除故障的方案。冷機(jī)狀態(tài)排煙發(fā)藍(lán),但機(jī)油消耗正常的,與燃料有關(guān),視為正常。
發(fā)動機(jī)排煙一般應(yīng)在發(fā)動機(jī)暖機(jī)狀態(tài)時檢查,通過發(fā)動機(jī)低速、中速、高速及加速過程中排煙顏色的變化進(jìn)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