[haastec]

I disconnected the belts and the noise is still there. I know for sure its not the spindle motor bearings as they were just replaced. Im 99% sure that its just gear slap although the video may not show that. When I turn the motor or encoder spline back and forth I hear a slap from the gears right under the encoder spline. Now if I spin the motor by hand fast enough for it to get a few revolutions the gear teeth are engaged with each other and I dont hear the slap. So I need to figure out why the gear slap is there when the machine is running. Can something electronically cause the motor to slow down and speed up for a split second causing the gears to slap like that? Im talking like milliseconds......just enough for the gear teeth to lose contact with each other then recontact causing that slap noise. The RPM display only fluctuates 1 rpm so it seems as if the encoder motor is ok but who knows. The encoder belt looks good, no missing teeth...I dont have a new one to compare it to so I cant tell how worn it is if at all.

I have a VF3 of the same model year and its so quiet you can barely hear it running. I would consider swapping the encoder motor from that machine but I cant be down both machines right now....I only have 2.

it is possible that the encoder, belts and/or pulleys for the encoder could give those kind of results. If you haven't already, I would remove the encoder. Inspect the belt good, and just as important look at both pulleys good. Most likely they are both aluminum and they will wear out. There should be a noticable flat between the encoder pulley teeth and make sure the teeth are not twisted. The pulley mounted at the transmission can be harder to inspect but look at it closely also.

If unsure, I would replace all three items for the encoder; belt, pulley @ encoder, and pulley @ gearbox FYI the pulley at the gearbox is sweat fitted onto the GB shaft, but comes on/off easily with a quick heat up with a torch. A new one should be made out of steel and will last much longer. If they havent been changed in a long time, it's still cheap insurance for future issues even if it doesn't fix your current problem.

Good luck!