Mystery piece on Camper...

Hi..My dad recently passed away and I am selling his camper. I found this piece on it and have no idea what it is. It has a pipe coming out of it and wires..It is rusty. I am wondering if it is something he put on as the informnation about the van does not show it. Thanks in advance!

http://learntosail.net/piece2.jpg

It looks like the generator is falling (has fallen) out of its bracket. I would have someone that is familiar with RV generators to take a look at it and make sure that the fuel is shut off (can run on gasoline, diesel or propane0 before you drive the van very far.