Johnson 115 oily residue

[Mike Lammert]

I own a 93 j115tlats outboard. When I run it at home, instead of ear muffs, I like to fill a large rubbermaid tote with water and run the motor with the foot submerged as its much quieter, and not forced. I let the hose run in the tote to keep full and fresh. However after letting it run for 10 or 15 minutes I notice an extreme amount of oily residue, sludge, or unburned oil. Globs of it. It gets on everything, like the sides of the bucket and hydro fin. Is this normal? I believe that its not just because its in the bucket, because I find myself washing it off of my transom after I use the boat, but its a much thinner layer as it can disperse more easily in a large body of water. Anyone else get this? Tell me what you think.

 

[racerone]

Re: Johnson 115 oily residue

very normal when idling one of these motors.

 

[71Windsor]

Re: Johnson 115 oily residue

Yep normal as it gets your exhaust vents through the prop usually turning submerged so you dont see any build up when your on the water. Two strokes burn oil and gas so the excess burnt oil must be evacuated with the exhaust. Unlike a 4stroke where oil doesn't make it to the firing side of the piston.

 

[Mike Lammert]

Re: Johnson 115 oily residue

I understand the concept I just didn't realize that it produced quite that much. If every 2 stroke is producing this much no wonder there is such a huge environmental push to 4 stroke.

 

[Bosunsmate]

Re: Johnson 115 oily residue

yep, two stokes always get some percentage of unburnt fuel mix going through them as new fuel mix is used to flush the old out the exhaust which takes some of the new with it.
I suppose you might be able to get two stroke mixs with break up better in the water

 

[emdsapmgr]

Re: Johnson 115 oily residue

Possible both stats are stuck open, causing the engine to run cold at idle. This will affect combustion, possibly excess oil out the prop. Check the cyl head temps with a laser gun. You need to see 143-150 degrees at idle when floating normally in the lake. probably less in a cold bucket of water...

 

[Faztbullet]

Re: Johnson 115 oily residue

Also crossflows are worse about this vs a looper motor....