1.There is sound in the cylinder
(1) The cylinder falls into the foreign body or broken valve piece, remove the foreign body or broken valve piece;
(2) the top of the piston and the cylinder head top collision, should adjust the clearance;
(3) the connecting rod big head tile, small head bushing and piston cross hole wear is excessive, should be replaced;
(4) piston ring excessive wear, work in the ring groove impact, replace the piston ring;
(5) There is water in the cylinder.
2. There is sound in the valve
(1) inlet and exhaust valve group is not compressed, should tighten the valve chamber cover fastening nut;
(2) the valve plate spring is damaged and replaced in time;
(3) The combination bolts and nuts of the air valve are loose, tighten the nuts;
(4) the clearance between the valve plate and the valve cover is too large, adjust the clearance, and replace the valve plate when necessary
3. Sound in the crankcase
(1) the connecting rod is excessively worn and replaced with a new tile;
(2) connecting rod bolts are not tightened and tightened;
(3)The flywheel is not installed tight or the key is too loose, should be installed tight;
(4) the main bearing is damaged, replace the bearing;
(5)The oil retaining ring on the crankshaft is loose and replace with a new oil retaining ring.