Precautions for use and maintenance of Deutz engine intake and exhaust valves
(1) Inspection method of valve sealing
The quality of the valve sealing directly affects the working performance of the diesel engine. Therefore, the valve must be checked for tightness after a certain period of use or after grinding. When inspecting, place the cylinder head end-side upward.
①Line inspection method. Use a soft pencil to draw several lines on the valve cone surface perpendicular to the sealing tape. Place the valve into the valve seat without installing the valve spring. Turn the valve 1/4 turn and take out the valve for inspection. If the lines are interrupted at the sealing zone, it means the valve sealing performance is good; otherwise, the valve should be ground.
②Gasoline (or kerosene) inspection method. First clean the valve and valve seat, then install the valve spring, valve guide and other parts, pour gasoline or kerosene from the intake and exhaust pipes, if no leakage is found after a few minutes, it means the valve seal is tight Good; otherwise, the valve should be ground.
(2) Install the valve correctly
① Before installation, clean and wipe all parts thoroughly.
② Coat the valve stem with a little engine oil and insert it into the valve guide.
③ Put the inner and outer springs (the inner spring is left-handed and the outer spring is right-handed) on the valve stem.
④Use the valve lock clip to fix the valve spring seat on the valve tail tapered surface, ensuring that the lock clip, the valve tail surface and the valve spring seat fit closely. After assembly, use a special sleeve to push against the locking plate and tap it several times with a hammer. Then stand the cylinder head on its side and tap it several times with a hammer to flatten and tighten the locking clip.
⑤ After installing the valve, shake the spring seat by hand to check whether the valve stem and spring seat are loose, and whether the two locking plates are installed correctly. If there is any problem, reassemble it.
⑥ Place the chamfered side of the flat washer next to the fixing nut of the cylinder head bolt, and use a torque wrench to tighten the fixing nut evenly in a certain order and with the specified torque several times to avoid over-tightening.
