My johnson 15 hp has a puddle of black oil on the floor beneath it. I'm pretty certain that it's residual from combustion. I use the boat for slow trolling. I've got a bunch of conficting advice on the subject so I came here for clarification. Here's some of that advice:
1. De-carbonize the motor using sea foam and change the plugs.
2. Switch from Pennzoil to Johnson/evinrude 2-cycle oil
3. Get a prop with less pitch
4. Use plugs with a higher heat range(this is crazy nonsense)
5. Clean carb to make sure excess fuel isn't dumping into the cylinders
6. Test the ignition system voltages to make sure there's enough juice to the plugs
Numbers 2, 3 and 4 sound fishy to me as I would expect a motor to operate properly with the stock plugs as well as on most any TCW3 rated lube. The prop seems fine as well: seems to rev high enough at full speed.
I haven't had the carb off yet. It's a little more complex than my previous motor so I'm a bit intimidated. I'm hoping the sea foam will get the carb clean as well and was considering using a syringe to push it through the fuel intake on the carb(through flappers and float valve).
Am I correct in thinking it would be the float valve that could allow excess fuel into the motor?
Anyone have instuctions for morons on testing the ignition voltages?
Any other ideas or opinions on why there's so much unburned oil on my garage floor or how to diagnose/fix the problem?
Should I just accept that this motor runs dirty at trolling speeds?
Thanks... Tom
ADDITIONAL INFO: Hull is 15ft alum-v=200lbs. Prop is stock 9.5x10. Usual load with gear is about 700lbs. Stock plugs= L77JC4. Fuel= clear gas mixed 50:1 with pennzoil premium plus marine TCW3.
1. De-carbonize the motor using sea foam and change the plugs.
2. Switch from Pennzoil to Johnson/evinrude 2-cycle oil
3. Get a prop with less pitch
4. Use plugs with a higher heat range(this is crazy nonsense)
5. Clean carb to make sure excess fuel isn't dumping into the cylinders
6. Test the ignition system voltages to make sure there's enough juice to the plugs
Numbers 2, 3 and 4 sound fishy to me as I would expect a motor to operate properly with the stock plugs as well as on most any TCW3 rated lube. The prop seems fine as well: seems to rev high enough at full speed.
I haven't had the carb off yet. It's a little more complex than my previous motor so I'm a bit intimidated. I'm hoping the sea foam will get the carb clean as well and was considering using a syringe to push it through the fuel intake on the carb(through flappers and float valve).
Am I correct in thinking it would be the float valve that could allow excess fuel into the motor?
Anyone have instuctions for morons on testing the ignition voltages?
Any other ideas or opinions on why there's so much unburned oil on my garage floor or how to diagnose/fix the problem?
Should I just accept that this motor runs dirty at trolling speeds?
Thanks... Tom
ADDITIONAL INFO: Hull is 15ft alum-v=200lbs. Prop is stock 9.5x10. Usual load with gear is about 700lbs. Stock plugs= L77JC4. Fuel= clear gas mixed 50:1 with pennzoil premium plus marine TCW3.