Analysis on the causes of the difficulty in starting the cold excavator, white smoke and abnormal sound of the engine
With the advent of the winter solstice, the temperature has also dropped precipitously. It has been rainy and snowy in many northern areas. In this season, the excavator owners are worried about the difficulties in starting and the failure to start
Today, Xiaobian will take you to see the faults and solutions of excavators in winter. I hope to add a layer of protective armor to your machines
Fault phenomenon:
Entering winter, the temperature is getting lower and lower. Many car owners report the following phenomena when the engine is started in the morning:
1. It is difficult to start the engine, and you can only start the car after several times of ignition;
2. Abnormal sound during startup;
3. The engine emits white smoke;
Cause analysis
First of all, it is difficult to start the engine. The first thing we will think about is whether the battery is powered?
It is true that in winter, the battery is prone to power feeding, but according to the above fault phenomenon reported by the car owner, it is not the cause of the battery. Because the engine can be started after several times of ignition If the battery is fed, the starter will not reach the speed or stop running at all, and the engine will not start at all. What is the reason? This is one of the reasons I share with you today
Generally, when we sit on the cab seat of the excavator in the morning, we will power up the whole vehicle with the key before starting the engine. At this time, there will be several lights on the monitor: 1 oil pressure, 2 battery, 3 preheating indicator. Of course, other lights will also light up, but they will go out soon Under normal circumstances, as long as we start the engine, these three lights will also be turned off and off one after another, except for the failure of the engine, battery and generator
The yellow is the warm-up indicator. As I mentioned in my previous article, warm-up is required before starting the engine. When the warm-up indicator goes off after a few seconds of warm-up, we start the engine again. Especially in winter, warm-up is very important. Because there is no warm-up, the three fault phenomena mentioned at the beginning of the article will appear. This is the fault point analyzed today
Preheating principle:
Analysis on the causes of the difficulty in starting the cold excavator, white smoke and abnormal sound of the engine
From this figure, we can see that the glow plugs in the combustion chamber of the engine finally achieve preheating. After being energized, they heat the air in the combustion chamber and the cylinder wall structure. When the temperature in the combustion chamber rises to a certain temperature, it is much easier to start the engine
Therefore, this is one of the reasons why it is difficult to start the engine when the temperature is low in winter
Troubleshooting:
When the warm-up indicator on the engine monitor fails to light up, if the engine does not warm up, it will be difficult to start in winter. Then the fault point can be found in the following places:
A. Check all harness connections and leakage grounding related to preheating
B. If the coolant temperature sensor fails, the engine computer board will not receive the information provided by it and will not prompt QoS (preheating system) to perform the preheating task
C. The engine controller (ECM), all the signal collection and command output of the engine have problems, and there must be no one to work
D. If the preheating relay (hot wire ignition relay), fuse, battery and other basic electrical circuits fail, the power supply must not be provided to preheat
summary
Of course, there are many other factors that make it difficult for the engine to start in winter, such as: blockage and air leakage in the fuel circuit; Insufficient fuel grade, wax deposition, etc Therefore, when we encounter this kind of problem, we need to consider it step by step from easy to difficult. The cause of the fault we analyzed today can be clearly and simply judged from the preheating indicator when starting the engine
