What is this part?

[scski]

This is a little over 1.5 inches long, mounted to the engine lid on the underside. It has a mating part on the hull so this will be beside it, both pieces are just mounted with double sided tape.

The metal bar inside is magnetic.

 

[Mazdarx]

I don't think that mine has anything like that on it. It looks like the sort of thing you see on household security systems, not sure what it's doing on a boat though.

 

[scski]

Yeah it's odd. Definitely not a seadoo part, but no wiring or anything either.

 

[carl1269]

looks like some kind of piece from an alarm system

 

[scski]

Yep, that's it. It threw me since there was no wiring, and the transmitter part was missing - just the base plate there so it looked odd.

It's one of these, sans transmitter housing:
http://www.linearcorp.com/product_detail.php?productId=1178

I guess the PO didn't want someone stealing the battery while it was on the dock lift.