superpump ii setting off GFI switch

My outside plugs were falling apart, so I finally had an electrician come to fix them. They change the plug on my pump from a regular 3 prong plug to the one with the round 3 prongs that lock in place (one prong is L shaped), and put in that recepticle too. The setup is like this

top - new round plug
middle - two switches - one to power the round plug above, one to turn on pool light
bottom - 2 regular plugs with the GFI (I think that is what it's called Ground Fault Interruption?)

Turning on the switch for the pump trips the GFI every time. It always did, but the electrician didn't have the issue when he showed it to me, so I thought it was fixed. The electrician came back to finish a small thing, and said he still didn't have the issue, while I had to trip to GFI 10 times to get it to work.

So, those of you who know pumps, is there something in the pump that may be shorting or getting wet? I have a leak somewhere in the filter that drips around, but doesn't seem to be on the pump. Can this type of thing be repaired? It does seem to be on the pump side - not the plug side.

- betty