Finding oil on my spark plugs....

[mountforever]

I have a 1997 3.3 Johnson that I run for a weekend and its fine then the next weekend it won't get any spark. I usually swap out the spark plug and it goes. I have a feeling something is leaking oil on the the spark plug swamping it. When i pull it out there a bit of oil on it. Should it have some oil or none at all? Any help is appreciated.

[pvanv1]

4-stroke OB's should have clean plugs. 2-strokes will have some unburned fuel/oil residue.

If the motor is running too cold (say if thermostat is stuck open), it will foul plugs prematurely.

There's a good Johnson/Evinrude forum on iBoats as well.

[timebandit]

2 or 4 stroke?

[mountforever]

2 stroke. I don't think its running cold. Its been 65-75 degrees out everytime I've run the thing.

[AirbusDriver]

My 2 stroke lawnboy mower used to do this. The mixure was running too rich. I went down to a 32:1 ratio and it solved the issue. Mix the exact amount Johnson recomends and try that.

[AdamLein]

I had the same problem on my 1990 Evinrude 9.9 (two stroke), and can confirm the richness theory. I now painstakingly measure out 50:1 as per owner's manual and haven't had any starting problems.

Do you use one of those marked-out jars that is graduated for different ratios? The graduations are labeled according to the amount of gas you're adding; you fill to the appropriate graduation with oil, add some gas, swish around, and transfer to the tank. No more converting fiftieths of a gallon to ounces or whatever

[timebandit]

If the plug is a year old I'd replace it.

If the gas is over 2 months old I'd replace it.

When mixing small amounts of fuel I recommend getting a couple of small plastic bottles and filling them with the correct amount of oil for 1/2 gal or 1 gal (mark them with a perm. marker)then just pour it into a plastic can and add the correct amt of gas.

Almost any motorcycle shop or dealership parts department can supply you with a "RATIO RITE" measuring cup.

RATIO-RITE CUP from Aircraft Spruce

[Capnblu]

Are you using HIGH OCTANE gas? Do you know that the higher the octane #, the less volatile the fuel is? I have seen it a thousand times, guy thinks premium fuel will give more power, spends more on gas, and his motor doesn't have the compression required to run on premium. Plugs are always fouled, hard to start, no power, etc. Many 2 stroke oils are designed to run at 50:1 , many provide sufficient lubrication for 2 strokes at this ratio. Read the labels.

[timebandit]

My 8hp Yahama runs 100 to 1, it's an 1987.

[poopdeckpappy]

First I would lean out the fuel mix a little, if you're not happy with that then run a slighty hotter plug, if that didn't help I would do the top end job, with a service manual it would pretty simple and might even be fun for ya