DrewE, you are correct, but I think they were liquid cooled. Also, when we got our new fiver in 2004, I wanted to put one of them in big time. But the Hondas were just a tad larger than the openings in a lot of RV genny bays. So with a new unit I wasn't going to reconstruct and went with an Onan Marquis Gold 7000. I have cursed it and made many new words over that "what should be a boat anchor". Having had previous experience with the Onans on our telephone bucket trucks, mine is true to form. I used to walk RV lots at auto races and when you heard choking, puking, you knew there was an Onan nearby. And those Hondas and Yamahazees just running along providing you could even hear them.