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2019 Mercury Verado V8 oil leak and fuel sheen

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Charlie1932

New member
After issues with my 2019 newly delivered Mercury Verado V8 250hp outboards leaking oil, crankshaft oil-seal replacement and finally one complete block being replaced under warranty, a sheen of fuel can be seen on the water.
A joint investigation by my dealer and the manufacturer was launched.
Mercury’s conclusion: “ all internal combustion engines have unburned hydrocarbons that are part of the exhaust. The sheen on the water is unburned hydrocarbons, not oil from the lubrication system. The engines are operating normally”.
Can other Mercury Verado V8 owners comment on this?
 
That's an answer (post 1), for those of us who...."haven't just fallen off the turnip wagon"!
 
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????? That's what you get for $40,000 worth of outboard motors? No wonder why Yamaha is number 1 in USA......pretty sad! Why not just get one of these? Keep all your problems under one hood. Can't read invoice? Boat/motor/trailer $116,000.....IMG_20200216_155601380_compress2.jpgIMG_20200216_155454834_compress24.jpg
 
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As part of the investigation into the sheen on the water, several other 6 -and 8 cylinder Mercury outboards were tested. They all showed the same pattern. Unburned hydrocarbons in rhe water.
 
Charlie1932 said:
As part of the investigation into the sheen on the water, several other 6 -and 8 cylinder Mercury outboards were tested. They all showed the same pattern. Unburned hydrocarbons in rhe water.
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Ignore the uneducated comments.....

I would run the hell out of the new engine. There is always unburned fuel(Unburned Hydrocarbons) with a new engine. They will become less over time once the engine is seated...

I am sure if the "unburned Hydrocarbons" were out of allowable tolerances the egg heads in Fond du Lac will come up with a remap of the PCM....
 
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Right....just like the wise men at Boeing, eh? I may be uneducated, but not stupid. They should have built things right to begin with....they have had since 1949 to figure it out.......at Mercury! If they aren't broken in at 90 hours.....what are you saying? That's like 3,000 miles in a car......Nobody's perfect.....except one guy.....and he didn't live long on this Earth either.
 
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timguy said:
Right....just like the wise men at Boeing, eh? I may be uneducated, but not stupid. They should have built things right to begin with....they have had since 1949 to figure it out.......at Mercury! Nobody's perfect.....except one guy.....and he didn't live long on this Earth either.
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Have you ever noticed the lack of people searching for help on this page? Maybe you should pay attention....
 
I would surmise that our level of expectation of quality would be exponentially higher considering the very high price of today's outboard technology. Defects can occur but our expectations are not to be BS'd by the OEM stating a fuel sheen on the water on a new engine is normal. That's fine for a 1955 Johnson but not today. We ran the twin 300 Suzuki's with 22 hours on them yesterday to go offshore and saw no fuel sheen on the water, including idling for hours during doing a drift over wrecks.
 
Why did you leave out this, without a rebuttal?
"If they aren't broken in at 90 hours.....what are you saying? That's like 3,000 miles in a car."....
Now you have a second opinion here....can you answer?
The likely reason that folks don't often go here to Mercury/Mariner.....is that either these motors are pretty good, they don't break down, or they are so lousy.....that owners give up on them. Not because you like to pick on other techs that may suggest something different from YOUR suggestion.
Here's my question for Charlie: Did the dealer say why the crank seals were leaking?
 
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When I informed my dealer about the engines leaking oil, they stated that it was a known poblem. Mercury had just ordered to have the crank seals changed for all these engines.
i am not sure if the seals on my engines were actually leaking, because after the sealchange, the leaking did not cease.

The other Mercury outboards tested were definetely not new.
 
Thanks for that information, Charlie. I have had to make repairs myself because of "dealer" errors, this is not uncommon to see imperfection. So if Mercury admitted to defective seals and/or defective engineering.....it should be a simple assumption that the proper repair has not been accomplished. Now they are making excuses. There should be no oil on the water. By the way, why was one complete powerhead replaced on a "new" motor. I really have a bad feeling about your dealer, sorry!
I appeal to other techs to study this thread and I welcome any information. There is hundreds and hundreds of years experience here.....just a click away......granted, likely few of us may have intimate knowledge of a 2019 Verado, but common sense and experience based on comparable equipment, can be applied.
 
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Has to be the advertised 4.6.....279 cu in. If you do math, it comes out to 4.58 L. Think they introduced it in May 2018.
 
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Hey Mikey.....anything on your mind? Maybe you have more experience with these. They been around almost 3 years now.
 
Well , first thing is . I've not been to school on that motor. But it does have a supercharger. Now does new powerhead come with new supercharger ? ( seals) obviously ( oil) that can not foul plugs , but just unburnt . Now if Ive seen a few of these and fuel filter is at back (1 of them) on starboard side, with the mercury quick connect ( red. Connector) fuel line goes below back cowling , in mid section . I'm assuming they are water cooling VST. Down low. That's my opinion I'm guessing. The 4.56 or so-called 4.6 is so big there's no room for vst . that rear filter has instructions on how to get out.
So if it's oil or gas needs to be figured out.
 
Oil problem was fixed.
Regarding the fuel issue, Mercury reports that while starting a rich mixture is injected. As a result unburned fuel comes out of the exhaust. This can be seen on the water.
Also when running the engine at low rpm, unburned fuel can be seen on the water. Mercury reports this to be normal.
 
That is insane. How did that motor pass EPA regulations? Musta been like that VW diesel deal....tested with one ECM to pass regulations, then cars got a different one at production....they got caught, however, and had to buy back the cars....I know, my brother bought one and then Volkswagen bought it back. Models affected were 2009 to 2016.
 
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That would not go over well in our National Park. At least with straight gasoline it evaporates fairly quickly.
Reminds me of flying Twin Otters on floats, in Canada’s Arctic.
Upon engine shutdown the FCU, (fuel control unit) would purge, spitting a few ounces of jet fuel out a drain in the bottom of each engine cowl.
made for a slick much as you’ve pictured into the water on each side of the plane. Fuel/oil has almost no surface tension, & so a very small amount spreads over quite an area.
2 strokes are banned in Canada’s National Parks, mostly due the oil sheen that sometimes accompanies them.
 
Charlie1932 said:
Oil problem was fixed.
Regarding the fuel issue, Mercury reports that while starting a rich mixture is injected. As a result unburned fuel comes out of the exhaust. This can be seen on the water.
Also when running the engine at low rpm, unburned fuel can be seen on the water. Mercury reports this to be normal.
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Hello, I was wondering what was determined to be the source of your oil leak? You said it was still leaking oil after the upper crank seal was replaced? I just took delivery of a 300HP Mercury Verado and it has an oil leak. Dealer replaced the crank seal but its still leading oil. Thanks.
 
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