When the engine is running and not in gear, the prop moves slowly. My wife (who has a history with the boat) says that the prop has always done this. Is this "supposed to happen and if not, what is the problem?
It is not abnormal. Friction and gear lube will sometimes cause the prop to turn even if it isn't in gear. As long at it is turning much slower than it would if it were in gear with the engine idling I wouldn't worry about it.
I've seen props slowly spinning on boats being towed on the road.
Ok, now I've had my second cup of coffee and thinking clearly. I've had two outdrives and two engines on my boat over time. In no conbination did mine do this. I had to think about being up on the hard and running the engine on muffs and a hose. I have a B3 drive and my props DO NOT move when in neutral.
I have seen this before and don't think it is an issue. My best guess is that as th exhaust gases blow through the propellers inner hub it can cause a windmill affect against the struts that connect the inner hub to the outter hub.
PS: never grap the prop when the engine is running as dog clutches (Alpha drives and outboards) have been known to engage upon doing so as they can have slop due to wear over the years
1997 2400 SCR
5.7 Vortec / Bravo 2
Okay, sounds good! I just wanted to make sure this was not a symptom of a greater impending doom. Since "it has always happened", the boat has been well taken care of, and no one on here is concerned; no action is need!
My '97 3.0 LX with a B2 has done it as long as I have had it. I asked original owner and he said did it from new. It does spin much slower and sometimes not at all. Higher RPM's make it more likely to spin. And yes, only when on muffs out of the water. Considering the guy I bought it from polished the engine and handed me a books worth of mainenance logs for regular stuff all is good.
1997 1700SR "MaKs RAT attack"