in my opinion , 9 X/ c6 b* j; u) m: ?6 b1.the noise is coming from the gears .the engine oil lubricating the gear is not enough $ i! c9 y3 M/ f# U$ [, h' p6 V" @* l$ Y/ p7 g
2.the loadmatch of the Engine and the Pump is bad or the fuel filter has big resistance