pc150-1 pump issues

[tom.HD]

Hi, is it really nomal that the main pump of pc150-1 excavator vibrates and makes noise while it is in operation? everytime the operator moves the sticks/implements i can hear and feel the vibration coming from the hydraulic main pump housing. im curious since the last time it was checked by a mechanic i noticed a missing nut that holds piston block housing. im worried that something is off and possibly result in serious damage to the machine.

I'll really appreciate if someone could enlighten me with knowledge cause this problem is bugging us for a long time.

 

[skyking1]

there is a coupler between the engine and gearbox/pump. It is a common source of vibration when it is coming apart.