I would have thought it needed something.....when I took it apart there did not see anything and the service manual does not show one. The Yanmar dealer here has to be the world's worst run by idiots....she said it did not show anything on the parts manual. By the way ordered one and she forgot to get it. Used to be great when I could order online most parts and Yanmar put a halt to that. I find it hard to believe there would not be something. Think I'll do some more asking around before I put it back together....especially since it's so convenient to get to.