Trouble shooting of CPCD20 forklift truck working weakness
A CPCD20 type forklift, the 490 type diesel engine, the working process of the engine suddenly appeared to take the blue smoke, white smoke, and the failure to work.
Analysts believe that the blue smoke may be burning oil, possible causes: the oil level is too high; failure or excessive wear of valve guide catheter sealing ring; oil blockage by coke stuck or oil return hole; the piston and cylinder, piston wear gap is too large; piston ring assembly.
The causes of white smoke may be: combustion chamber inflow; oil supply advance angle is too early; a cylinder is not working well.
The cause may be unable to work: the injection timing is not correct; the cylinder pressure is not enough; poor intake, exhaust valve clearance adjustment made block; improper; low pressure oil to poor oil, the oil inlet; the connecting rod bearing and shaft neck surface plucking.
In summary, the inspection is as follows: check the oil surface, too high and the oil is thinner, black and yellow, smell of lighter diesel smell. Start forklift truck, exhaust pipe without water vapor, but has pungent oil generating flavor. Check the fuel supply advance angle of diesel engine is 7 degrees, normal. The cylinder is not working, the injector is disassembled, and the cylinder pressure is 3.48 MPa, normal. The injector was opened and it was found that the nozzle pair had been sintered.
Due to the sintering of nozzle, work III cylinder injector is always in the open state, and injected into the combustion chamber of diesel atomization to the combustion, most are discharged outside the cylinder, a small amount of leakage along the wall into the diesel oil pan, the oil sump oil level rising caused. While the excess oil was splashing and channeling into the combustion chamber, resulting in burning oil, blue smoke exhaust, white smoke, and unable to work due to lack of cylinder phenomenon. After the replacement of the oil and the fuel injector coupling of the third cylinder, the fault disappears.
