If the engine is running and there's no implement attached, the front lift arms on my CM274 slowly raise, even in float position. If I have an implement attached (like the mower), it weighs enough make the arms drop. But if I don't have an implement attached and I try to lower the arms by pushing down on them with my weight, they won't go down unless I turn the engine off. I haven't owned this very long and it's the first time I've worked on it without having an implement on the front. Is there some other control that I'm missing that will allow the front arms to drop while the engine is running?