The 6160A diesel engine is often used as a fixed power for power generation, irrigation and drainage operations. This article describes the experience of several maintenance tasks. 1, cylinder head and valve inspection and maintenance and installation of the 6160A diesel engine cylinder head is a single type, the cylinder head centrally installed fuel injector crack often occurs, because the top surface of the combustion chamber is a high temperature area, but also withstand the pressure of the largest Place, and here the cylinder head wall is thin, so it is easy to produce high-temperature rupture. Therefore, when using such engines, care should be taken not to make the outlet temperature higher than 80 degrees Celsius, and the inlet temperature should be strictly controlled. It is recommended to install a water temperature meter at the front of the pump to observe the inlet water temperature so that the temperature difference between the inlet water temperature and the drainage temperature is not more than 25 degrees Celsius. When inspecting the cylinder head, carefully observe the flat underside of the cylinder head. If there are any scars, cracks, or inconsistencies at the end of the cylinder head, repair or replace the cylinder head promptly. In addition, during maintenance, the air door must be carefully inspected. If there are spots or ablation at the air seal band, the air door should be reamed so that the seal ring width is between 1.5-2.0 mm. If the sealing ring is less than 1.5 mm, premature wear of the gas door can be easily caused, and if the width is more than 2 mm, loose sealing may occur and the compression ratio may be reduced. For longer time cylinder heads, the gap between the valve and the conduit should be checked. The gap should be 0.10-0.12mm. If the gap is too large, the oil can easily enter the combustion chamber from there, resulting in excessive coke formation and increased oil consumption. After replacing the new valve guide, re-tighten the air door when necessary to ensure that the valve will not seal properly due to skew. Check the thickness of the copper gasket before installing the cylinder head. Use a depth gauge to measure the height of the flat underside of the cylinder head and the depth of the groove. Calculate whether the preload of the copper gasket is 0.15-0.20mm. Tighten the cylinder head nuts diagonally at a torque of 550-600 Nm to further check the compression gap in the cylinder. This is an important part of ensuring the correct compression ratio. The specific method of checking the compression clearance is to turn the piston to the top dead center of compression, first measure the thickness of the cylinder head, and then measure the size of the piston crown to the top surface of the cylinder head. The two dimensions are subtracted. When the diesel engine is equipped with a supercharger, It is 12.0-12.3mm and it should be 11.5-11.8mm when no booster is available, and the compression clearance is 2.0-2.3mm. When the size is incorrect, it can be adjusted by adding or removing copper gaskets. 2. Inspection and maintenance of the piston connecting rod group The top piston combustion chamber of the 6160A diesel engine adopts a shallow ω pit, and the combustor pit size of a supercharger is 138 mm for empty sets, and 127 mm for an unpressurized machine. Before the connecting rod is installed, check the shaft for cracks, scratches, etc., and check whether the connecting rod bushes are loose and whether the oil holes are aligned. When inspecting the connecting rod bushing, the new piston pin can be inserted through the bushing to the middle position and shaken by hand. There is no obvious clearance and the rotation is flexible. If not, replace the bushing. When replacing bushings, hammering should not be used. Install on the vise; press the boards on both ends inwards until the bushings are flat. If the new copper sleeve is over-tightened with the piston pin, it can be used with a reamer reaming, or it can be polished with a fine emery cloth (polishing along the inner diameter circle, not skewed). The difference between the quality of the connecting rods of the same diesel engine shall not exceed 35g. The total mass difference of the connecting rods (pistons, connecting rods, piston rings, piston pins, retainers, bushings, connecting rod bolts and nuts) of each cylinder shall not exceed 60g. When installing the piston connecting rod set, the direction can not be installed wrong, there is a pit on the top of the piston, which is used exclusively for the small gas valve and should be towards the side of the exhaust pipe. The position of the connecting rod's bearing positioning port is toward the injection pump, and that of the lower shoe's cover is installed opposite to it. The connecting rod cover and the shaft's mark should be consistent to make it matched for use. It cannot be mixed. Before connecting, carefully check the connecting rod bolts to check whether the connecting rod bolts have necking, elongation, thread deformation, etc. For copper plated bolts, check whether there is any phenomenon of copper removal. If any of the above phenomena occurs, replace the new ones. Rod bolts, connecting rod bolt tightening torque 240-300Nm. 3, crankshaft inspection and maintenance and installation before installation, testing the journal size, journal arc and journal surface roughness. No scratches, bumps, and rust stains were observed with the naked eye. The oil passages were free from foreign matter and blocked. Check the deviation of the major axis coaxiality, it should be less than 0.04mm. Check for any impurities and burrs on the flange and the keyways and flanges. The keyway shall not be loose, otherwise the increased key may be used to cooperate so that the width direction is a tight fit, but the height direction should be 2/3 or 3/4 of the total height of the crankshaft keyway plus pulley keyway. When the crankshaft is installed, the main bearing cover should be tightly tightened in the middle and tightened at both ends. The tightening torque of the bolt is 240-280Nm. Note: It is normal to rotate the crankshaft after tightening the 4th main bearing cap. After tightening the 1st and 7th main bearing caps, it will be easier to rotate the crankshaft by hand. Otherwise, the bearing should be opened to inspect the bearing bushes, and if necessary, the bearing bushes can be scraped. When installing the main shaft, pay attention to the fact that there are oil holes in the middle and there are no oil holes in the lower tile. Do not install wrong. Connecting rod bearings without direction, the same group can be installed. After the crankshaft is installed, check the axial clearance. 4. Check of valve phase and adjustment of valve clearance Type 6160A diesel engine with supercharger, intake valve opens at 57 degrees before top dead center, and closes at 40 degrees after bottom dead center; exhaust valve is at 46 degrees before bottom dead center Open and close at 48 degrees after top dead center. By checking the phase angle of the valve, it is possible to directly observe the working status of the valve gear and the camshaft with the valve, and repair or replace it if necessary. The working order of the 6160A right turner is 1-5-3-6-2-4, and the valve clearance can be adjusted by the secondary adjustment method. Rotate the flywheel clockwise to the top dead center of the 1 and 6 cylinders (see the flywheel mark). At this time, if the 6-cylinder valve is in the open position, the gaps of the six valves 1, 2, 3, 6, 7, and 10 can be adjusted; Turn the flywheel 360 degrees. At this time, the 1-cylinder valve is in the open position and the remaining 6 valves can be adjusted. The specified cold clearance is (0.350.06) mm. In the actual role, the intake valve clearance can be adjusted to 0.35mm, the exhaust valve clearance can take the upper limit value, that is 0.35-0.40mm, slightly larger than the clearance value of the intake valve.
