1. Insufficient power of Oshiba Deutz engine

The main reasons for the lack of power in the Oshiba Deutz engine:

(1) Gas path:

① The air filter is blocked

② The intake pipe is discounting or blocked

③ Air leakage of intercooler and pipeline

④ The supercharger is damaged

⑤ exhaust brake damage

⑥ Improper adjustment of valve clearance

⑦ exhaust pipe leakage or blockage

⑧LDA pipe screws are loose and air leaks

⑨ Supercharger bypass valve opens in advance

(2) Oil circuit:

① tubing discount

② Engine diesel filter block

③ The injector atomization is not enough

④ Diesel oil pump pump pressure is insufficient

⑤ Insufficient oil return

⑥ The return oil pressure regulator is damaged

⑦ Damaged hand oil pump

⑧ Low pressure pipe diameter is too small

⑨ Engine filter element is reversed

⑩ Fake filter element

(3) If the Daichai Deutz engine has a failure of insufficient power, it shall be detected according to the insufficient power detection procedure. The detection procedure of insufficient power is as follows:

① Check high idle speed with a tachometer Depending on the configuration of the engine, the high idle speed should be 6-8% higher than the rated speed. The basic calculation formula is as follows: High idle speed = rated speed x 1.07; If the high idle speed is not enough, check that the fuel handle is not jacked up to the high idle limit screw.

② Check the injector, whether there is leakage and cavitation caused by insufficient primary oil pressure.

③ Check the low pressure oil circuit system, low pressure oil circuit pressure will directly lead to insufficient power and fuel injector cavitation.

The oil supply pressure of the low pressure oil circuit in the 0.5MPa system is (no-load) :

The 1500-1899 r/min > 0.42 MPa

The 1900-2300 r/min > 0.50 MPa

> 2300 r/min > 0.53 MPa

The pressure detection point of the low pressure oil circuit should be after the oil outlet of the fine filter (that is, the oil inlet of the crankcase). If there is no measurement space at this position, it can be measured in front of the oil return valve (i.e. at the crankcase outlet). Note: At the rated speed, the measured pressure at the crankcase outlet should be about 0.10MPa lower than the oil at the crankcase inlet. The following are the causes of low pressure oil circuit pressure:

- Whether the fuel primary filter and fine filter are blocked

- Check whether the oil return valve is faulty

- Whether the flow resistance in the pipeline from the fuel tank to the oil pump is too large

- Whether the oil pump provides sufficient oil supply pressure

Another reason is whether the flow resistance in the pipeline from the return valve to the fuel tank is too large. If the resistance is too large, the oil return will be insufficient and the fuel temperature will rise (the fuel temperature should not exceed 80 ° C). Under the condition that the filter element is not blocked, if the pressure is not enough, check or return the oil valve (part No. : 02111519).

If the pressure is still not enough, check whether the flow resistance in the pipeline is too large, and directly use an oil drum to supply oil in front of the oil pump, so as to determine whether the resistance caused by the supply line and initial filtration from the oil tank to the oil pump provided by the OEM is too large.

The inner diameter of the oil pipe in front of the oil pump should not be less than 12mm, and the fuel pressure at the entrance of the oil pump at high idle speed should be greater than -0.05MPa, and the engine that meets the emission of Euro 2 should be greater than -0.035MPa.

If the pressure is still insufficient, the oil return amount should be checked, the oil return end of the return pipe should be removed from the tank and inserted directly into an empty bucket, and the oil return amount of the engine at 1min high idle speed should be more than 8L.

(4) Check the charge air pressure and exhaust temperature of the Dashadoitz engine at full load. Only when the speed is reduced from the high idle speed to the rated speed, the engine output can reach full load.

At full load, the pressurization pressure in the intake manifold should reach at least 0.13MPa, and the exhaust temperature (at the measurement point of 100mm after the supercharger) should be 450℃-480℃. The method of measuring the pressure of charging air is divided into static measurement and dynamic measurement.

Static measurement value: 0.05MPa

Dynamic measurement value: 0.13 ~ 0.15MPa

If the oil supply is sufficient and the boost pressure is still insufficient, the exhaust back pressure should be checked and should not exceed 500mmH2O.

If the vehicle exhaust brake is damaged, check the position of the internal valve disc, if it is close to the semi-closed state, it will lead to the lack of engine boost, affecting the engine power.

Example 1: In March 2005, a DEUTZ engine in Fujian Ningde Service Station had power shortage. Firstly, the oil circuit and air circuit were checked according to the test program. After actual measurement, the oil pressure of the oil circuit was 0.50MPa(the measuring point was at the oil inlet of the cylinder block), the measured static boost was 0.02MPa, and the dynamic boost was 0.05MPa, which did not meet the requirements of DEUTZ. It is concluded that the main cause of the fault is the gas circuit fault. Remove the exhaust brake part and re-measure the static boost volume of the engine to reach the DEUTZ standard value of 0.05MPa. Check the exhaust brake and find that the internal valve disc is in the semi-closed state. After adjustment, the dynamic pressure measurement is carried out to reach the standard value of 0.15MPa.

Example 2: A DEUTZ engine in Nanning service station was found to be underpowered, and the measured static and dynamic boost volume met the requirements. The measured high idle pressure of the oil circuit was 0.42MPa, and the measured outlet pressure of the diesel oil pump was 0.6MPa, which proved that the vehicle was underpowered due to the blockage of the diesel filter element. The fault was removed after replacement. 2. The engine is smoking

(1) Black smoke: It is due to incomplete diesel combustion, in which the incomplete combustion of carbon forms free carbon, suspended in the gas with the exhaust gas discharge, it becomes black smoke.

(2) Cause of failure:

① The air filter is too dirty, and the intake resistance is too large. The intercooler is dirty.

② The oil supply of the injection pump is too much or the oil supply of each cylinder is too uneven.

③ Low speed oil reduction device damaged. (Connecting air line leakage)

④ Poor injection of fuel injector.

⑤ Low cylinder pressure.

⑥ Diesel is of poor quality.

⑦ Governor wear.

⑧ The concentrated solenoid valve coil is burned

(3) Diagnosis and exclusion methods:

① Remove the air filter, check the cleaning of the intercooler, if the diesel engine black smoke phenomenon disappeared, indicating that the air filter is too dirty, should be cleaned.

② If the air filter is good, the diesel engine emits black smoke when running at idle, indicating that the oil supply under idle conditions is too large. The fuel injection pump should be checked.

③ If the fuel injection pump is in good condition, the fuel injection pump should be checked for fuel timing.

④ If the oil supply timing is correct, the single cylinder oil cut-off method can be used to check the working condition of each cylinder. If the change of a cylinder after oil loss is not obvious, and the black smoke phenomenon disappears, it indicates that the cylinder is not working well, which may be that the oil supply of the branch pump is too large, the spray quality of the injector is not good or the cylinder pressure is too low, and it is excluded after diagnosis.

If there is no problem, it may be that the quality of diesel is too poor, resulting in incomplete combustion, and the diesel should be replaced.