water in lower unit, 2 stroke 15hp Merc

Rainman · 08-12-2009, 06:34 AM

Maybe somebody can help me out with this dilemma.
I changed out the oil in the lower unit of my Merc 15hp 2 stroke. The old oil came out black. I replaced it some Evinrude Hi-Vis gearcase lube.
Now the darn oil is coming out a creamy color. So I replaced both plugs and washers with brand new, but water is still somehow getting in. It did not leak prior to initially changing out the oil .
Do I need to use Teflon tape, or maybe some aluminum anti-seize, or perhaps some plumbers dope ??
I am perplexed.

fishkisser · 08-12-2009, 07:04 AM

The gear oil coming out black usually means more than normal wear ...
Sounds like a seal might be going out or some fishing line got wrapped around the prop shaft , you can have it pressure tested to check the seals ...
How many hours between lube changes ...?

Rainman · 08-12-2009, 08:58 AM

I know that the oil I originally drained was past due, but my point was to show that it's only leaked since I changed it out. It ran only 1 short trip of a couple of hours on the Willy out of Buena Vista when I drained it again, ostensibly to flush it out, considering the oil had been so black to begin with. The oil is pretty creamy, not just a little bit.
Now, even just sitting in the garage, with a flashlight a person can see leakage coming from the top plug, w/o having been run at all. It takes a week or so, but the leak is there and visible to the naked eye. Not enough to drip down to the floor, but a leak nonetheless.
A visual inspection of both sets of threads doesn't show any cracks, nicks, pits etc... I'm thinking a good working over with a wire brush might be the next step. I dunno.

honker1 · 08-12-2009, 04:04 PM

I am just going to wing this because I have no idea the color of the Evinrude Hi-Vis gearcase lube is. I know Mercury has 2 differant color of lube. One dark green and one beige color. That said, now for my second idea.
Can you double up the little gaskets. Mine had as many as 3 on the plug. Guess the owner before me didn't remove the old gaskets, just added a new one. Also maybe a small O-ring may be the answer.
You could also get one of these and put a pressure test on the lower unit to see if the seal is leaking, but it sounds like you know the source of the water infiltration. Good luck...
http://www.harborfreight.com/cpi/cta...emnumber=92474

Rainman · 08-12-2009, 04:47 PM

The Evinrude oil is a greenish color, not beige or the usual oil color. That tool you sent the link to looks pretty sweet, and for only $20 bucks. Multi-purpose too.
I'm wondering if the new gasket is maybe the wrong type. I think the old one was the usual black rubber type, while the new ones I got at the marina is more of a white hard plastic. The new ones look to have a lil too much slop for me, so I'm gonna get new ones.