prop spins during idle

[gibsonman]

I recently purchase a boat with a 1976 merc 850 motor and the prop slowly turns in reverse when in idle. I have not had the boat in the water yet but noticed this was happening when I had it hooked up to the water hose and had the transmission lever clicked in to the neutral posistion. I can stop the blade with my fingers so it appears that it is just barely engaged. If I move the shifter out of neutral and barely into the forward posistion I can find a very narrow spot with the shift that will cause the prop to stop between forward and reverse. I am hoping that this is something that I can repair myself. Thanks in advance. Steve

 

[Hooty]

Re: prop spins during idle

If it's not making a grinding noise, like it's partially in gear, it's o-k. What's happening is the lube in the l/u is acting like a fluid coupling and causing the prop to move.<br /><br />c/6<br /><br />Hooty

 

[gibsonman]

Re: prop spins during idle

That is the kind of answer that I was hoping to hear. I do not hear any type of grinding so what you say makes a lot of sense. I am not sure but I suspect that in the water that there might be enough drag on the blade to cause it not to turn or maybe the boats weight might keep it from trying to slowly go in reverse while in idle, we'll see what happens. <br /><br />I purchased this boat from my Uncle and due to health reasons it hasn't been on the water for a couple of years. This boat was my Uncles pride and joy as he bought in new and took very good care of it and did regular maintanance, but I am wondering if I should go ahead and change the grease out in the bottom unit. Thanks again for your reply. Steve.

 

[Fouled Plug]

Re: prop spins during idle

This would be a great time to change the lower unit lube. If it looks good, just replace with new (and use new gaskets on the screws)

 

[gibsonman]

Re: prop spins during idle

I really appreciate everybodys input here. I will take the advice on the lube job.<br /><br /> Thanks again, Steve