Water in lower unit

[Onedown]

So I went to do my annual lower unit oil change yesterday and was surprised to see a drizzle of water come out first as I turned the screw open. There was also some very, very fine grindings covering the magnetic bottom screw.

I was just wondering how normal/serious this issue is.

The motor is a 1980 9.9 Johnson 2 stroke.

Oh, I did have one issue a few years ago when I found the bottom screw missing completely. The gears were stuck for a day or so. Someone had told me to fill it with oil and let it sit for a couple days and see if it frees up. It did thankfully, and has been running decent since, but that had to do some damage I would think. A buddy told me I had bull$h!t luck that it even freed up at all. Since all that I have changed it 2 springs now without any water in there.

I have never taken the lower unit off the motor either.

Thanks in advance,


Jay

 

[BaileysBoat]

Re: Water in lower unit

Best to do the lower unit oil when you put the engine away in the fall. Then the corrosion damage is not compounded by freezing damage.

Very fine filings are normal on the magnetic screw. The drain and fill plugs should have new gaskets or O rings when the fluid is changed.

Use the Mercury high performance gear lube. It is designed to hold water in suspension.

Time to pull the gear case and do the pump. Got a manual?

 

[Vic.S]

Re: Water in lower unit

If there is water in the gearcae then it should be investigated and the cause rectified. More serious if you are operating on salt water than on fresh water perhaps.
It might simply be due to the sealing washers on the drain and level plugs having been reused or it might be one of the seals failing. They do not tend to heal themselves... replacement is the only option.

You choice really whether to get the thing pressure /vacuum tested to identify the leak or to replace all the seals and be done with it.

If you are going there to replace any seals then change the pump impeller at the same time.

Metal particles may have come from the dog clutch if you tend to engage gear gently. Hopefully not from bearings .. but with its history who knows.

It sounds as though you are doing your annual service in preparation for the coming summer. You should do the service as part of the winterisation at the end of the season. Now is not the time to find it has been sitting with water in the gearcase or with any other defects that could have been fixed during the winter.

 

[mikesea]

Re: Water in lower unit

I had bull$h!t luck ,Brother ,that is putting it mildly.The water you are now experiencing MIGHT be residual from before.BUT,I would pressure test it.Fortunatly for me ,,I always had access to a testor.But ,have heard many people have made them from old fill plugs,and adapters that allow filling from various assemblies,OR,replace the oil and check it periodically,the fine filings are probably natural wear.If you had serious damage from the big episode a while back,you would have known it by now

 

[Onedown]

Re: Water in lower unit

Wow guys, thanks for the quick replies. I hear what you're saying about fall maint & oil changes, I will start that from here on out. I don't want to find a major problem 2 days before walleye opens. :redface:

I don't have a manual. I didn't know I had to change those sealing washers on the screws when I do the changes either, so that could be it right there. I've had this motor for 4 years now I think.

I'm going fishing this Sat and will rechange the oil and seals after. I'm curious to see if there's any more water in there after I've been out.

As for changing the pump, I've never had the lower unit off and will need to really research that procedure first.


Jay

 

[71Windsor]

Re: Water in lower unit

4 years with out a impeller service id start my research on that right away

 

[Vic.S]

Re: Water in lower unit

As for changing the pump, I've never had the lower unit off and will need to really research that procedure first.

For most of what you'll ever need to know about the 9.9 see http://www.sschapterpsa.com/ramblings/OMC/OMC info.htm

 

[Onedown]

Re: Water in lower unit

I guess I've been neglecting the poor thing. Never knew much about this sorta stuff - just gas and go. :redface:

I'm gonna have to get that lower unit off and check the water pump and any other issues. How long is the impeller supposed to last?

I'll get an idea if anything is wrong tommorow. Planning to wet some lines for most of the day.

Vic.S, thanks for the link, lots of info there.


Jay