Possible exhaust leak in F150 four-stroke?

[angler53]

On the F150TXR there is a exhaust port just below the rear cowl lock. I think I remember being told that it's there to relieve exhaust pressure build-up when idling.
There has been this somewhat wet, black substance bleeding down the back of the motor from this port. It also bleeds out around the bottom of the plastic cover.
I took it back to the dealer last year during break in after a powerhead replacement. They acknowledged that it was bleeding something and they said run it, don't worry, it'll probably stop in time.
Well, I now have 100 hours on it and it still does it. I don't do much idling and I don't troll any either.
Today during my usual day after clean and inspection (it's a pilot thing. I do it to everything mechanical) I removed the plastic wrap around cover just to look-see. Inside the cover and the back of the motor in this area is black with suet. This motor does not smoke at start-up, cold, or hot. It doesn't smoke when idling or running either. I ran a few tanks of gas through it without ring-free just to see if that was causing it and it actually got a little worse.
Have any of you F150 operator's noticed this? Is it just one of those things and really nothing to worry about?
I'm taking it to a service center this week to replace the trim switch and I wonder if I need to mention this to the tech?

[G I Mike]

Yes, i noticed the same thing for the first time on my f150 when pulling it out of the water after a 9-day trip with lots of running and trolling. Sort of a black exhaust film. First time i noticed it and i have about 90 hours on mine.


Let me know what the techs tell you.

Gi mike

[angler53]

I have not been able to take the boat in as yet but I did talk to the service manager about it. I have talked with a master tech that said a small amount of suit is expected, it's exhaust. Any oily suit indicates combustion/fuel issue and needs attention. I'll keep you informed.

[seahorse]

Many times the soot is due to a fouled or non-functioning thermostat or a leaking pressure relief valve. The motor is not reaching operating temperature and the engine computer thinks its warming up and delivers a richer fuel mixture to the cylinders, which wastes fuel and leaves soot stains. A temp sender that is reading too cold will do the same thing.

[ripley]

i know of this problem because i run twin 150's yamahas. there are 3 or 4 things 1. your trolling and not using ring free. that saying your cylinders are canboning up which in this case "makes oil" check your dip sticks. 2. you have a hole in your fuel pump diaphram.3 you have 1 or both thermostats going bad or bad. 4. you are getting water in your fuel,ether by vent intake on the side of your boat. or more than likely good old ethonol gas. after running mine in the flordia keys for 5 years i've been their done that. if your lucky your injectors are not messesed up.