90hp Johnson residue on plugs

Another few question about my 2000 90hp Johnson V4. While it always cranks, it takes several 5 sec. choked key turns with a freshly primed bulb (good 87 octane and TC-W3) then seems to idle rough even after it is warm. Maybe I'm expecting too much but why doesn't it crank up on the first or second key turn? Anyway.... I removed the Champion spark plugs and found that all four had a wet, black, exhaust smelling substance on the fire end. I thought this may be a symptom of over carbonization so I performed a decarb with Seafoam Deepcrank. After decarbing and running the engine with the water ears, I replaced the plugs with new Champions (I can't recall the number but they are the correct plugs) and gapped them at .30. I took it to the lake yesterday and after several choked key turns it cranked and idled the same as it did before. It ran fine at speed as it always has.<br />I got it home, checked the spark plugs and found that the new plugs now have the aforementioned "stuff" on them. Is this normal? Shouldn't the plug tips be clean and dry especially after running the engine hard? Could it be running too rich? Thank you!

Re: 90hp Johnson residue on plugs

Assure that you have no air leaks on the fuel line from tank to VRO pump.This will cause not only hard starting but oil rich mix when running.Starting two stroke outboards can be a little tricky till you get the hang of it.Squeeze primer bulb until completely firm.Push in the keyswitch while cranking and once the engine fires ,repeatedly push in and out on the primer key switch until it settles.Calculate how much oil your engine is using in relation to fuel so we can determine whether it is running oil rich.One way to do it is to mark the level line on your oil reservoir and then add 8 oz. of TCW 3 oil and mark the new level.Do the same with your fuel tank to 3 gallons of fuel and watertest.This will insure that the engine is running 50:1.

Re: 90hp Johnson residue on plugs

Ob,<br />I checked the lines and found no leaks and all of the lines are in good shape. I'll start keeping tabs on the oil vs. gas consumption. I do believe it may be running rich. Thank you for the valuable insight!

Re: 90hp Johnson residue on plugs

Clint......Two stroke motors will never have "clean" plugs do to the oil that gets burned, but over oiling will foul them. Also usually after a decarb, it is a good idea to take the boat out and run it hard to get all the carbon out, running at idle on the muffs is not as effective. Also try priming the motor with the key pushed in for about 5 seconds then turn to start with it pushed in, then after that you can bump the primer a little bit to keep it smooth, if needed, like ob mentioned. If need be you may want to raise the fast idle lever a little to get it going at first. Good Luck.