Engine crankshaft bearing assembling method and engine crankshaft bearing connecting structure

The invention discloses an engine crankshaft bearing assembling method and an engine crankshaft bearing connecting structure. Firstly, an oil seal is arranged in a needle bearing, and a roller pin of the needle bearing is pre-coated with a lubricating coating; then the needle bearing is pressed into the metal lining in advance in an interference mode, and then the whole structure of the needle bearing and the metal lining is pressed into a rear end hole of the crankshaft in an interference mode through a press-fitting punching tool; one end of the press-fitting beating tool is inserted into a hole of the needle bearing, the hammering part of the press-fitting beating tool is fully attached to the end face of the metal lining, then the other end of the press-fitting beating tool is connected with a high-frequency air gun, and under the reciprocating acting force of the high-frequency air gun, the press-fitting beating tool hammers the end face of the metal lining at high frequency, so that the end face of the