I have a 2008 Mercruiser 3.0L that is hard to steer. I disconnected the steering cable and the helm turns easily. I don't see any grease nipples, and the manual doesn't say how to grease anything but the cable and the steering pin, both of which are fine. At the bottom of the outboard portion, there is what looks like a slotted plug that a large, flat screwdriver would fit. I was thinking maybe it covered a grease point. I took a quick shot at taking it out, and it didn't turn so I stopped. Does anyone have advice on what the problem could be and/or where I can find tech data for it?