Milky Prop Exhaust

[JJGulley]

I have a 1977 Evinrude 15hp engine model # 15704M

Just recently i started to get a milky belch when I start the engine and on further examination of the prop, the inside exhuast port on the prop has a milky coating. I drained the lower unit and no water or mily residue in the LU. The oil level was slightly low, but no sign of water leakage. At the same time I noticed that I only have a dribble of water exiting from the water pump indicator. I removed the LU, inspected the water pump and it looks like new since it was just replaced about a year ago. While the LU was off I noticed that the exhaust port through the engine was also coated with a layer of this milky paste like film. I cleaned all of this out and it then re-appeared about a week later. I'm thinking I have a seal going bad in the LU, but how would this relate to the lack of water from the water pump indicator . is it possible the milky paste has plugged somthing up?

Any adivice would be greatly appreciated

 

[Will Bark]

Re: Milky Prop Exhaust

That milkey goo is unburned oil and is normal; my 77 15hp does it all the time, in the lake you wouldn't even notice it. Try running a weedeater line up your pee hole and see if the streamdoesn't get stronger. good luck

 

[Chinewalker]

Re: Milky Prop Exhaust

I concur - nothing to do with the lower unit seals. Everything to do with unburned fuel.

 

[JJGulley]

Re: Milky Prop Exhaust

Thanks for the responses, i just don't understand I'm using fuel from the same cans on two other motros without any issues. the enginge is running great without any issues, maybey I'l change the plugs and run some cleaner through it. This engine has never done this in the past.

 

[Rick.]

Re: Milky Prop Exhaust

I agree with the above posts. No concern. If you troll a lot it will be worse. At the end of the day run it full throttle for 5 to 10 minutes and there will be much less oil drainage after shut down. Best of luck. Rick.

 

[boobie]

Re: Milky Prop Exhaust

Is the mtr getting up to proper operating temp at both idle and wot? Checked your thermostat lately ?

 

[Rick.]

Re: Milky Prop Exhaust

That's a great point boobie. Thought of that after I posted. Glad you did.
I also have to say I see more milky exhaust with my 9.5 than my other engines. The others produce more of a black/brown oil. Not sure why but I will be checking the stat now. Rick.

 

[JJGulley]

Re: Milky Prop Exhaust

never changed the t-stat since the engine was new. I'll have to look into this. Thanks

 

[Rick.]

Re: Milky Prop Exhaust

With the engine up to operating temp. you should be able to hold your hand on the head for about a slow three count. If it is stuck open you'll be able to hold there much longer. Rick.

 

[nphilbro]

Re: Milky Prop Exhaust

What's your plug gap? I had to open mine up a bit since I just use mine as a kicker. What do the plugs look like now? I was running both too rich and small gap. Opened up the plugs and leaned it out. No more oil dripping down the midsection either.

LeeRoy also talks about running 100:1 for trolling. I haven't tried that yet since I run both off the same tank.

 

[Ibl0wstuffup]

Re: Milky Prop Exhaust

My 115 was doing that when my thermostats were stuck open. I checked it with an ir temp gun and it was only hitting 90f.