Hi Ranger1

1. No suction strainer.

2. Clearance has been checked as soon as I noticed the problem still existed.

3. When the cavitation occurs, there could be one or both make solenoids open or closed on vessels. System feed solenoids only close for defrost in the storage ( Checked hot gas flow during defrost to make sure it wasn't loading the vessel ) The plates manually fed by opening a shutoof valve to feed liquid through a pre set hand expansion valve that have all been recently set by me. ( 1- 1.5 turns open)

4. Pump has a vent on the suction for pump out and to release vapour during cool down. Checked this valve to make sure it is holding, also tried running with it cracked open but this valve is normally closed when pump is running.

5. The BPR has been tested for proper operation and I have jacked it open and operated with the valve in the line throttled but still have the same problem.

Keep in mind that both pumps on this vessel are acting exactly the same way. Each pump has its own bypass and seperate piping. The system has been in operation for 25 years with no major issues regarding these pumps.

Thanks
CanadianIce