15 hp Johnson Problem

[shane52501]

I have a 1975 15HP johnson that I am having trouble with. My problem is that when I run it I have white cream, looks like water and oil, coming out of the prop. The motor runs fine, and I do not have any water in the lower end grease, but it is mixing somehwere. Also it does not pump water as good as I think it should,though it does not get hot. Any help on figuring this out would be appreciated. Thanks

 

[mars bar]

Re: 15 hp Johnson Problem

Did you do a search in the archives, most likely it's the oil in your pre mix that's coming from your exhaust. Not enviromentally friendly but sounds right. The older ones did that. Do a "search Thead" and type "oily water mixture".

 

[Jogin]

Re: 15 hp Johnson Problem

was just working on a 2000 50 hp johnson that was doing the same thing, pretty sure it is not an issue and is just what mars bar had said

 

[dew2]

Re: 15 hp Johnson Problem

I have a 1975 15HP johnson that I am having trouble with. My problem is that when I run it I have white cream, looks like water and oil, coming out of the prop. The motor runs fine, and I do not have any water in the lower end grease, but it is mixing somehwere. Also it does not pump water as good as I think it should,though it does not get hot. Any help on figuring this out would be appreciated. Thanks

Did you drain some lower oil to see if its milky?

 

[viciousfishes]

Re: 15 hp Johnson Problem

Does the water that its pumping look like its kind of just spraying a mist? If so I know its not as pretty as motors now a days but thats what its supposed to look like

 

[shane52501]

Re: 15 hp Johnson Problem

It really doesn't look like it is even misting until I goose it. Then it really squirts. It stays cold though. And yeah I drained all of the lower end oil out and there is no milky look there. I guess the only reason it really worries me is because I am trying to sell this motor and I guess to me the milky look is not a good sign lol.

 

[Jogin]

Re: 15 hp Johnson Problem

maybe run a compression test on it, just to see if you are getting a lot more escaping through exhaust than there should be, the motor I was talking about earlier ended up having a 30 pound difference from one cylinder to another, since I am sure yours is only a single cylinder, check to see what the manual says for compression, or i suppose you could do a leak down on it

 

[bktheking]

Re: 15 hp Johnson Problem

Look at your plugs, are they both the same in appearance or is one clean, if so you have water intrusion, if not- all good.

 

[dew2]

Re: 15 hp Johnson Problem

It really doesn't look like it is even misting until I goose it. Then it really squirts. It stays cold though. And yeah I drained all of the lower end oil out and there is no milky look there. I guess the only reason it really worries me is because I am trying to sell this motor and I guess to me the milky look is not a good sign lol.

You say its running good,No water in the lower,The little mist when at idle is good because you say at higher rpms it really squirts water out,Which is great.So your trying to find where the milky looking oil is comming from and its out of the prop.The only oil that gets milky in appearence would be out of the lower,its milky because water enters and the gears spinning whip it up like a milkshake.But as you said no water in lower.A pic would be the best in this case.But I say sell it.everything is great as you say.Some blackish oil comming out of drain holes near the lower is normal,but its black and will smell of gas.

 

[ONERCBOATER]

Re: 15 hp Johnson Problem

might easily just be the oil your using happens to look milky when it is mixed with gasoline, run through an air pump (two stroke engine) fired and burned, then mixed heartily with the water and exhaust in the mid section. personally I think your engine is fine, as long as compression is good and even and spark plugs don't look washed (same for piston tops). I have found over the years that different oils look diff coming out the tail end of outboards.

Sean

 

[oldcatamount]

Re: 15 hp Johnson Problem

That happened to me and my '88 15 hp Johnson. I changed the plug gap to .040 (as per owners manual) and the problem went away.

 

[shane52501]

Re: 15 hp Johnson Problem

Thanks for all the good info. I am going to go check and try some of the things mentioned, and I will give updates from there. Thanks again for all of the replies.

 

[sterilecuckoo58]

Re: 15 hp Johnson Problem

I noticed my '97 9.9 2-stroke Johnson (x-long tiller rope) was oozing this browonish creamy-ish stuff into the bay when I raised the engine. As we were planning a 5-day voyage to move our Vivacity north, I was worried it would need a lower end overhaul.

An old salt of a diesel and OB mechanic chuckled, and explained that it is the oil in the fuel. He pointed at the 150-hp 2-strokes in the shop and put the discharge I was watching dribble out in to perspective. I am planning to rig a catchment system to collect the goo and put in the trash for incineration, but wonder about the procedure when I raise the engine once the sails are aloft.

I have considered using the vegetable based 2-stroke oil I use for my lawnmower, but everyone who knows these engines has shaken their heads from side to side dubiously.

For the moment my engine needs cooling system repair so I am not dribbling any petroleum based slimes into the harbor.

As much as I hate to say it, we probably have to pollute that little bit and be happy anyway.