New boat Owner, 25HP Johnson Leaking Oil (PICS)

Hello,

I have recently purchased a 14' aluminum boat with 2005 25Hp Johnson outboard. The seller ran the engine multiple times for me prior to purchase. It starts right up, purred and seems to run flawlessly. I had since bought the boat and stored it in my garage for the last 3 months or so. I have notice some oil leaking from a small hole in the bottom end of the shaft. Not sure what it is or what needs to happen. I am planning on taking it in to be serviced prior to use but just am curious if this is really bad.




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The drain hole is there to drain water out of the leg. What you are seeing is unburned 2-cycle oil. Switch to OMC oil and eventually the
problem will go away. The inside of the leg is full of this junk and it will just time to drain out. If it really bothers you remove the lower
unit and clean out the inside of the leg. You don't have a problem. Drainage from this hole is normal and to be expected. Protects the
motor if it's subject to sub-freezing temps.

Yep just unburned fuel. Walmart carries BRP Evinrude semi synthetic oil for about $30/gallon. I’ve burned that oil pre-mix at 50:1 in my 1979 9.9HP and it has almost no smoke and the oil residue like yours is pretty much non existent. Also, make sure you have good spark plugs in the engine. Strong spark is the best way to ensure the cleanest burn.

KJ

Normal. Take the motor out and run the hell out of it.

That's an awful lot of oil drainage. Just wondering, was the tank fuel line connected while in storage for that 3 months? It could have been slowly forcing fuel through the motor, where it picked up carbon particles which turned it black. Harmless and it will go away when you run it. Moral of the story: Disconnect the fuel line when not in use.

He ran it for you and perhaps others.----Was it on a hose ?----Those motors idling on a hose will put lots of oil through the motor that is not used.----It drains out as you see.----It alarms a lot of folks.

What's the model number of that engine?

In my 30+ years experience... that's the most drainage I think I've ever seen. Was the fuel hose attached to a 6 gallon portable fuel tank and left hooked up to the engine in a tilted position? If so a buildup of pressure in the fuel tank could have had the fuel mixture being forced through the carburetor.

To ease your mind... or confirm a lower unit seal problem.....................

Find the large regular slotted drain/fill screw in the lower portion of the lower unit.... there will be a similar one higher up on the lower unit which is the oil level screw. Loosen the drain screw just enough to have some oil seep out to compare with what you are seeing spread all over the top edge of that cavitation plate.

What did you find..... water, good gear-case lube/oil, same stuff as on cavitation plate?

Gear-case is to be filled from that bottom hole until it flows out the top oil level hole.... HiVis Gearlube.

You may want to have a pressure test done of the lower unit... no higher than 7 to 12 psi.

DO NOT EVER remove a philips head screw from the lower unit if it exists unless you are qualified to rebuild it. That would be a long shoulder type pivot pin screw that retains the internal shift lever.

Let us know what you find.