It was a hot summer. A user from the town of Qing Mu Guan called and said that when his Carter Cat336D was on the upslope, the lower exhaust pipe was sprayed out of the oil. The user stopped the car on a flat ground, pulled out the machine oil ruler, and found the scale had exceeded the line. The user could not understand why the oil would not increase, so call the salvage phone. After the phone, I drove to the site of the user's work.
After the scene, first check the oil increase, after inspection, the engine internal oil increased obviously, find a clean towel paper, the oil on the oil tape on the paper, found that the oil droplets spread quickly, with the nose smell, oil droplets have obvious diesel flavor.
Here, it can be basically confirmed that the reason for the increase of oil is mixed with diesel, but the problem is where the diesel is from? One possibility is that the oil pump and the actuating pump are together, it is possible that the two pumps are mixed with two kinds of oil due to the seal damage, and the other can be the flow direction of the nozzle because of internal wear and pressure. Go in the engine.
Open the valve chamber cover, wipe clean the nozzle with a clean rag, clamp the fuel back to the oil pipe with pliers (prevent the pressure of fuel pressure relief), and then let the driver pump oil manually and observe whether the nozzle is leaking. After careful observation, it is found that the nozzle in the sixth cylinder of the engine has obvious leakage when the fuel pressure increases. Because the sixth cylinder is close to the exhaust pipe, the high temperature at work usually leads to premature aging of the inner nozzle.
After finding the problem, disassemble the sixth cylinder nozzle, because of the oil in the cylinder head and the remaining oil in the fuel oil channel, the gravity cause will flow down the mouth to the cylinder. If not, it is easy to put the injector to the top of the piston rod, so it is also necessary to find a pumping unit to pump out the oil in the cylinder. Finally, wipe the mouthpiece with clean cloth and clean the carbon in the cylinder. After that, replace a new nozzle and install the valve cover back.
There is no end here. After the injector is installed, the oil is replaced, the oil filter is replaced, the ET (excavator detector) is connected, the code of the injector is refreshed, and the engine ECM is better matched with the new fuel injector. At this point, the whole maintenance process is completed.
The Cat 336 and Cat 340 series of Carterpillar are used by the C9 engine, and the sixth cylinder nozzle aging is a common phenomenon of this engine. It is easy to appear after 5000-6000 hours. After this problem, the fuel will be discharged into the engine and the oil is blended together. The most direct effect is that the oil gradually increases and the oil pressure will be low. So, if it happens that your equipment is using this engine, and the number of equipment hours is about 5000 hours, I suggest that you should observe the level of the oil level more, and find out the service personnel to come to check as soon as possible.
