What is the cause of 75kw valve leakage of diesel generator set?

1. Diesel generator set valve leakage.

When the valve is leaking, it is difficult to start the diesel engine, and the exhaust pipe is discharged, smoke, and fuel consumption increases, which will be accompanied by abnormal noises.

Causes of valve leakage:

1. The working surface of the valve and valve seat ring is abrasive, ablated, and the sealing is poor and causes air leakage;

2. There is carbon deposition on the working surface of the valve and valve seat ring, and the valve is not closed tightly and the air leaks;

3. The gap between the valve and the valve guide is too large, and the valve stem shakes, resulting in air leakage due to the loose closure of the valve;

4. The valve stem is astringent or stuck in the valve guide, and the valve cannot move up and down;

5. The valve spring loses its elasticity or the spring is broken.

The solution of valve leakage: after eliminating the cause of ignition system and fuel system failure, the cylinder pressure can not be measured when the fault is not determined, and the cylinder pressure or intake manifold vacuum degree can be determined more accurately, and when the cylinder pressure is measured, the cylinder pressure of the valve leakage is lower than that of other cylinders.

When the valve of the diesel generator set leaks, it is difficult to start the diesel engine, the exhaust pipe is discharged, smoke, fuel consumption increases, and abnormal noise occurs. Causes of valve leakage:

1. The working surface of the valve and valve seat ring is abrasive, ablated, and the sealing is poor and causes air leakage;

2. There is carbon deposition on the working surface of the valve and valve seat ring, and the valve is not closed tightly and the air leaks;

3. The gap between the valve and the valve guide is too large, and the valve stem shakes, resulting in air leakage due to the loose closure of the valve;

4. The valve stem is astringent or stuck in the valve guide, and the valve cannot move up and down;

5. The valve spring loses its elasticity or the spring is broken.

Performance of valve failure of gas generator set:

The speed of the gas generator set is unstable during operation, the exhaust pipe has a "protruding" sound, and the smoke exhaust is abnormal (black smoke or blue smoke).

1.Check at the water filling port of the water tank, if there is a blister, it means that the cylinder gasket between the cylinder and the water jacket is leaking.

2.Listen to the seat hole of the injector of the adjacent cylinder, and the sound of air leakage indicates that the two cylinders are connected, which is caused by the cylinder gasket being washed out.

3.Remove the air filter and listen to it at the intake pipe, if there is a leaking sound, it means that the intake valve of the cylinder is not sealed and is leaking.

4.Listen to the exhaust pipe, there is a leakage sound, it indicates that the cylinder exhaust valve is not tight.

5.Slowly release the brake, shake the crankshaft to move the piston down from the top dead center, listen to the oil port of the refueling machine, the air leakage sound is always large and the change is small, it indicates that the piston ring or ring wear is serious. If the leakage sound changes from small to loud, it indicates that the cylinder is worn in a conical shape.

1. When the elasticity of the piston ring is weakened, the piston ring should be replaced.

2. If the piston ring is glued to the piston ring groove, it can be opened and filed with a triangular scraper, and then it can be installed in the piston ring groove to make it rotate freely.

3. The valve head and the valve seat are not tightly fitted, if the ablation is not serious, it can be re-grinded, then cleaned with kerosene, and then checked with kerosene, such as in 3

There is no kerosene leakage within min, which proves that the seal is good.

4. If the valve seat insert is loose, it should be replaced.

Method for detecting the wear of cylinder bore of 250kw diesel generator set:

Check the cylinder status of the diesel generator set is an important basis to determine whether the cylinder is worn and confirm whether the generator needs to be repaired, such as due to the improper coordination of the piston and the cylinder, or the engine works at high temperature for a long time, or due to the piston pin clamp ring selection, improper installation and loosening, breaking, in the pin seat hole and straining the cylinder wall, it needs to be repaired in time. Method of detecting the wear of the cylinder:

1. Before measuring, use a shovel blade to scrape off the carbon deposits in the upper mouth of the cylinder, and wipe the cylinder wall with cotton yarn dipped in automobile oil to reduce the error.

2. Select the appropriate measuring rod according to the diameter of the cylinder, bring the fixing nut, and screw it into the lower end of the measuring cylinder gauge.

3. Insert the measuring rod at the lower end of the measuring cylinder gauge into the upper part of the cylinder hole, observe the watch needle while screwing out the connecting rod, and lock the fixing nut when the watch needle rotates a circle.

4. According to the wear law of the cylinder, measure the maximum wear of the cylinder in all directions within the piston stroke range, and then rotate the dial of the measuring cylinder to make "0"...

Method for detecting the wear of cylinder bore of 250kw diesel generator set:

Check the cylinder status of the diesel generator set is an important basis to determine whether the cylinder is worn and confirm whether the generator needs to be repaired, such as due to the improper coordination of the piston and the cylinder, or the engine works at high temperature for a long time, or due to the piston pin clamp ring selection, improper installation and loosening, breaking, in the pin seat hole and straining the cylinder wall, it needs to be repaired in time. Method of detecting the wear of the cylinder:

1. Before measuring, use a shovel blade to scrape off the carbon deposits in the upper mouth of the cylinder, and wipe the cylinder wall with cotton yarn dipped in automobile oil to reduce the error.

2. Select the appropriate measuring rod according to the diameter of the cylinder, bring the fixing nut, and screw it into the lower end of the measuring cylinder gauge.

3. Insert the measuring rod at the lower end of the measuring cylinder gauge into the upper part of the cylinder hole, observe the watch needle while screwing out the connecting rod, and lock the fixing nut when the watch needle rotates a circle.

4. According to the wear law of the cylinder, measure the largest part of the cylinder wear in all directions within the piston stroke range, and then rotate the dial of the cylinder to align the "0" position.

5. Rotate the cross-section of the measuring cylinder gauge at 90° to measure the most worn part, and the reading pointed by the pointer is the roundness deviation value.

6. Move the gauge cylinder table downward, so that the measuring rod is located outside the piston ring movement area, and the reading pointed by the pointer is the cylindrical deviation value.

7. Use a micrometer to measure the length of the cylinder rod when the gauge hand points to "0", which is the diameter of the cylinder after wear.

1. It is found that the valve head and the valve seat cooperate with the cone surface of the carbon deposit, burning, peeling, the valve and the valve seat can be manually ground when it is slight, if the valve sealing performance can not be restored by grinding method, the valve seat can be rehed first, and then the valve and valve seat can be grinded, and when it is seriously damaged, it should be replaced.

2. The gap is too small and is caused by the loosening of the adjustment screw, which should be checked and adjusted regularly.

3. The gap between the valve stem and the duct is large, and the valve stem is resistant to bending or valve head deformation, and it is necessary to replace the new hidden parts.

4. If the valve stem is stuck in the duct due to carbon deposits, it can be cleaned with gasoline after removing the carbon deposits, and the paddle can be reused. The clearance between the valve stem and the duct is enlarged, and it can be adjusted to the specified clearance value.

5. When the locomotive is operating, it is not possible to slam the throttle and change the speed frequently, so as to prolong the service life of the valve spring, and the spring must be replaced if it is too soft or broken.

6. Pay attention to check whether the pressure reducing mechanism is working normally.

1. It is found that the valve head and the valve seat cooperate with the cone surface of the carbon deposit, burning, peeling, the valve and the valve seat can be manually ground when it is slight, if the valve sealing performance can not be restored by grinding method, the valve seat can be rehed first, and then the valve and valve seat can be grinded, and when it is seriously damaged, it should be replaced. (For reference only: (Fujian Yanan diesel generator set:.)

4000-080-999) Ya Xiaonan will answer for you).

2. The gap is too small and is caused by the loosening of the adjustment screw, which should be checked and adjusted regularly.

3. If the gap between the valve stem and the guide pipe is large, the valve stem is bent or the valve head is deformed, it needs to be replaced with new parts.

4. If the valve stem is stuck in the duct due to carbon deposits, it can be cleaned with gasoline after removing the carbon deposits, and reused for reuse. The clearance between the valve stem and the duct is enlarged, and it can be adjusted to the specified clearance value.

5. Pay attention to check whether the pressure reducing mechanism is working normally.

6. The diesel generator set can not slam the throttle and change the speed frequently during operation, so as to prolong the service life of the valve spring, and the spring must be replaced if it is too soft or broken.

The valve leakage of the 300kw diesel generator should be checked, and the main reasons for the valve leakage are:

1. The sealing ring of the valve and valve seat is ablated;

2. The sealing ring of the valve and valve seat is too wide or the sealing ring is stained with sundries;

3. The valve stem has serious carbon deposit, occludes the duct, and the valve stem bends, resulting in the valve closing is not tight;

The valve spring of the kW diesel generator is broken, or the elasticity is weakened.

5. The fitting gap between the valve stem and the duct is exceeded due to serious wear.