Oil residue on the back of my engine

[JAZZedBW]

I have Oil residue on the back of my 1984 70hp. Johnson. I had it rebuilt but there is this oil residue there. I don't know what its from but I checked inside the compartment and everything checks out fine. <br /><br />Does it have anything to do with the fuel? Its a manual-mix motor. Oil and Gas go into the fuel tank. Does this have any effect? Thanks<br /><br />JAZZ

 

[Solittle]

Re: Oil residue on the back of my engine

Probably unburned fuel which contains oil. <br /><br />Bout a year ago we were down in the Fla Keys on the shore. There was a high performance outboard in the water in front of us. He took off and went strait out so that we were looking directly at the stern. The cloud of unburned fuel comming from that motor was unbelievable.

 

[JAZZedBW]

Re: Oil residue on the back of my engine

So what should I do, Solittle?<br /><br />JAZZ

 

[rickdb1boat]

Re: Oil residue on the back of my engine

Jazz<br /><br />About all you can do is make sure you are using the correct fuel mixture(50:1) and make sure your carbs are adjusted correctly. Every outboard puts out unburned fuel/oil mix out the exhaust especially at idle and low speeds. Try seating your low speed screws lightly and the turn them out 2 turns on each carb and work from there. Turn them in/out evenly on each carb until the idle sounds the best. Do this in small increments.(1/8 turn) You may be running slightly rich at idle. Make a note of how many turns to seated when you start, so that you can return them to their original position if needed.

 

[JAZZedBW]

Re: Oil residue on the back of my engine

Rick,<br /><br />My engine does run a little on the rich side. I had the motor rebuilt and "bored out" so-to-speak. The guy who did it claims that it would be better on speed and fuel. He was in charge of adjusting all the carb's and so on.<br /><br />I do watch my mixture carefully. 50:1. Basically I have a 13 gallon tank, and 50:1 = a quart of oil in each tank of gas when empty. What I do to make it precise, is that I fuel up at a half of a tank and then add a half quart of oil. This way you keep your oil precise.<br /><br /> Another potential problem <br />When its a really hot day out and I get done running the boat, and put the engine up for night, it seems like fuel/oil is not leaking but is on the water when I raise my engine up. What can be the matter there? I wondered about it and it stops. It's not a continuous flow onto the water.<br /><br />JAZZ

 

[Solittle]

Re: Oil residue on the back of my engine

Jazz - There is nothing wrong with what you are doing now. Clean the residue off once in a while and enjoy.

 

[JAZZedBW]

Re: Oil residue on the back of my engine

Oh ok I didn't know if it was bad or not.<br /><br />Thanks for all replies!!!<br />JAZZ