Entering winter, the temperature is getting lower and lower, many high latitude areas in the morning when the engine starts the following phenomena:
1. the engine is difficult to start, several ignition before the car.
2. even if the engine starts, the idle speed is unstable, white smoke, or even flameout.
reason analysis:
Last time, we analyzed the two reasons why the engine is difficult to start when the temperature is low in winter:
1. Battery feed
2. Insufficient preheating.
At the same time, we also summarized a lot of other reasons, such as: fuel oil road blockage, leakage and other problems; Fuel oil label is not enough, wax, etc.
All of these factors will cause winter startup difficulties, but not all of them. Today, we offer you an unexpected failure point. Before we analyze the problem, let's talk about winter. A clumsy way to start the machine in winter. I don't know if you have ever seen such a situation: in the early morning of winter, a lot of construction machinery and equipment parked on the roadside, some drivers use open fire to bake fuel tank, bake oil pan, and pour these parts with boiling water, why do you know? Use fire to bake the oil tank because the bottom of the tank has frozen, or because it is too cold, the diesel oil in the tank has waxed, and the oil is too sticky to start lubrication.
However, whether it is open fire roasting or boiling water poured into the oil tank and oil sump, these methods may not be able to solve all the problems in front, so, without further discussion, uncover the mystery, the fault point is: high pressure oil pump, or more specifically, the plunger coupling inside the oil pump, etc.
Cold shrinkage + condensation
In winter, all kinds of diesel engine equipment will enjoy the special courtesy of these two natural phenomena. The interior of high-pressure oil pump and plunger couple will be taken care of by cold shrinkage, and diesel oil will be taken care of by condensation, condensation and even waxing. In this case, the gap between the plunger and the coupling will become larger, leading to high pressure leakage, there will be insufficient oil supply situation, coupled with the condensed diesel oil is difficult to form oil film, even if into the combustion chamber, the amount is insufficient, it is still easy to start? It's too difficult!
It is the same with the cylinder cylinder and piston we said in the last period. After the low temperature is taken care of, the seal between cylinder cylinder and piston will not fit closely.
As a result, the machine will not only have trouble starting, even if started there will be idle instability, white smoke, or even shut off the situation. Troubleshooting: Of course, these reasons are due to a very important ring junction decision in engine production process: the thermal variation coefficient of the coupling. As users, we can't change these coefficients, but we need to change the effect. How do we solve it? Stupid, but effective:
1, spray starting liquid combustion. Fuel assisted diesel combustion is provided in the intake system.
2. Pour boiling water on the high-pressure oil pump. Let the cold-shrink plunger expansion, reduce the sealing clearance, at the same time to the pump condensation of fuel heating, liquefaction, the formation of oil film to increase the sealing.
3, the car before the fire, the use of electric heating or the form of a mattress package, to the high-pressure pump heating.
conclusion:
Winter is very cold, not only to pay attention to their own warmth, but also to keep your car warm, otherwise, it will strike.