Not sure where to post this.

I bought a Becker VT 4.25 Vacuum pump on ebay as it was 'faulty'. This is to 'power' my vacuum table.

I was hoping that it was not really faulty and that I may be able to repair it. I didnt pay much for it, so worth a chance. The machine came without the faceplate but following the manual below, its a 3 phase motor that can be run using single phase. The motor is 0.9KW or around 1.1HP.

http://www.ecovac.com.tw/pdf/rotary_.../oi_vt4.25.pdf

After messing around with starting capacitors, I manage to get the machine to spin up. It runs up to full speed however whenever I add any load, the machine stalls. I found that the wiring wasnt 100%, so I rearrange the wiring. I measure around 6.7 Ohms across 3 distinct coils which seems to imply that the motor is fine.

So, as the motor cannot take much load before it stalls, is it faulty? Could it be too large to run on single phase (Im using a starting cap, no running cap and it stays in circuit all the time, no logic to remove it from the circuit).

Im tempted to buy a 4KW spindle and VFD although I dont strictly need it. The VFD could be used to see if the motor works on 3 Phase. These pumps are expensive and if it works for my vacuum table, it will be a bargain.

Thoughts?

Thanks