Re: Lower Unit slippage
You say you put a new prop on...was it a brand new one, or a used one?<br /><br />Also, can you describe the "slipping" symptoms a little more clearly? Do the engine RPM's suddenly go up when you're under hard acceleration? Are there any other noises?<br /><br />Here's the deal: <br /><br />If the engine RPMs go up under hard acceleration, but only then, and there are no noises, and the RPMs drop back to a more normal level, with propulsion, when you back off, it's likely that the hub is slipping on your prop. There's nothing in the lower end that can slip in that way.<br /><br />Unless you have a brand new prop, you'll need to check for slippage by marking the outer rim of the prop and the hub, then running the boat to the point where the slippage occurs. Remove the prop and check. If the marks no longer align, then the hub is slipping. <br /><br />If, on the other hand, you hear a banging or rattling noise and the RPMs go up, then it's likely that a clutch dog is disengaging, putting the motor out of gear. That's a more serious problem, and will require a teardown of the lower end. The point is that there is nothing in the lower end that can slip smoothly without making noises, then re-engage without making noises. That kind of slipping has to be the prop hub.
