Excessive Smoke From Johnson 15

[JackHunter]

Hi Guys im new to the forum,

I have a 97 Johnson 15hp it had been rebuilt approximatley 20hrs ago long story short i have only put 10hrs on it since i have owned it and the previous owner had not used it for 12 months or so. when i got it i did the usuall , plugs, impeller, gearcase oil, full clean and inspection over everthing else.

it seems that it is blowing excessive smoke, i have changed my oil brand a couple of times and even leaned out the oil mix a little to 60:1 instead of 50:1 and it makes no difference.

i was hopeing that someone here could give me a little advice on where to look next as i am out of ideas

 

[DJ]

Re: Excessive Smoke From Johnson 15

Hi Guys im new to the forum,

I have a 97 Johnson 15hp it had been rebuilt approximatley 20hrs ago long story short i have only put 10hrs on it since i have owned it and the previous owner had not used it for 12 months or so. when i got it i did the usuall , plugs, impeller, gearcase oil, full clean and inspection over everthing else.

it seems that it is blowing excessive smoke, i have changed my oil brand a couple of times and even leaned out the oil mix a little to 60:1 instead of 50:1 and it makes no difference.

i was hopeing that someone here could give me a little advice on where to look next as i am out of ideas

"excessive smoke" is a personal opinion. Yes, they do smoke, especially cold.

Other than that, how does it run? Maybe there is something hidden that we're not seeing.

 

[Daviet]

Re: Excessive Smoke From Johnson 15

Proper ratio is 50:1, mix it that way. The smoke is produced by the amount of oil mixed in the gas.
At least when you see smoke you know you don't have to worry about siezing an engine.

 

[levi_tsk]

Re: Excessive Smoke From Johnson 15

yeah no kidding.... your gonna ruin that motor.... and over a little two stroke smoke??c'mon? - i personally like the smell plus it runs the biting bugs off
i love the smell of two strokes in the morning

 

[DJ]

Re: Excessive Smoke From Johnson 15

Hi Guys im new to the forum,

I have a 97 Johnson 15hp it had been rebuilt approximatley 20hrs ago long story short i have only put 10hrs on it since i have owned it and the previous owner had not used it for 12 months or so. when i got it i did the usuall , plugs, impeller, gearcase oil, full clean and inspection over everthing else.

it seems that it is blowing excessive smoke, i have changed my oil brand a couple of times and even leaned out the oil mix a little to 60:1 instead of 50:1 and it makes no difference.

i was hopeing that someone here could give me a little advice on where to look next as i am out of ideas

All comments aside. If you think you have a running issue, let us know, perhaps we can help.

 

[JackHunter]

Re: Excessive Smoke From Johnson 15

I know that 2 stroke is meant to smoke a little but this smoke its that bad its not funny

i have a couple of photos of it, also it becomes a real problem when im running at slow speeds will start to foul the plugs, there are a lot of 6knt speed limits and opening the throttle to clean the plugs up is not an excuse with gold coast water police $500 fine every time

 

[Daviet]

Re: Excessive Smoke From Johnson 15

What plugs are you running? Have you tried adjusting the low speed needle valve, maybe running a little rich at idle.

 

[JackHunter]

Re: Excessive Smoke From Johnson 15

running the plugs recomended by Johnson cant think of what they are at the moment they should be Champion, i cant see any thing to adjust i looked for that because my 6 had one right next to the tiller but theres nothing there :S
but the smoke is thought the whole rev range not just at idle

 

[Daviet]

Re: Excessive Smoke From Johnson 15

You didn't post a model number, it seems that there is a couple different versions. See item #22.
Early production.
http://www.ishopmarine.com/ishop/js...nown&isFrPG=false&forItemCode=&pCode=C0149979
Late production.
http://www.ishopmarine.com/ishop/js...nown&isFrPG=false&forItemCode=&pCode=C0149978

 

[JackHunter]

Re: Excessive Smoke From Johnson 15

I just had a look at that, i have the late production carb, i will go and have a look at the motor for the slow speed needle.

 

[JackHunter]

Re: Excessive Smoke From Johnson 15

There is no adjustment on mine, this is what mine looks like
http://http://www.boats.net/parts/search/BRP/JOHNSON/1997/J15RLEUC%201997/CARBURETOR/parts.html
see part 17

I do appreciate any help i can get,
i have asked around a few shops and they have given me 3 different possiblities and thier prices start from $300 just to actually diagnose it so

But they are
1. Carb need to be rebuilt
2. The Plate under the Flywheel is not aligned with the carb properly
3. Bad oil Mix (this is the one that said try 60:1)

 

[levi_tsk]

Re: Excessive Smoke From Johnson 15

you can do a carb rebuild yourself .... and a link and sync but it may be your carb .......

also what brand of oil are you running?? is it brand new?

heres your carb kit ...

http://www.marineengine.com/newparts/part_details.php?pnum=OMC0439073&ptype=&Engine=&Model=

 

[Mas]

Re: Excessive Smoke From Johnson 15

Smoke...or steam??? After the "rebuild," was the head retorqued?? Pull the plugs...do they look "steam cleaned?"

Mas

 

[JackHunter]

Re: Excessive Smoke From Johnson 15

I have tried
Shell Nautilus
Something the guy at the shop said works well and is cheap (used 5 ltrs fuel with it and threw the rest out)
the one that works the best is the Valvoline TC-W3 NMMA Compaible

but they all produce the same ammount of smoke

 

[JackHunter]

Re: Excessive Smoke From Johnson 15

no its definatley smoke, I do a bit of work on cars so it was one of the first things i checked,
plugs just look just like they should if the motors fouling a little.

 

[raczekp1]

Re: Excessive Smoke From Johnson 15

maybe termostat is taken out, so motor runs cold all the time.
cold motor usualy smokes litle more

 

[JackHunter]

Re: Excessive Smoke From Johnson 15

I did not think of that, will look when i get back home. just i dont think that would justifiy this much smoke, the pics i posted do not do it justice

also i just remembered between 1/4 1/2 throttle just before it gets up on the plane it seems to run a tiny bit rough (you hardly even notice) unless i've been trolling all day then it splutters and runs terrible untill WOT then runs perfectly again.

 

[JackHunter]

Re: Excessive Smoke From Johnson 15

just had a look at the thermostat, its still there and looks like it is in a fairly good condition

 

[JackHunter]

Re: Excessive Smoke From Johnson 15

guys, I may have stumbled onto something.

i called the local salvage yard to get a quote on a carby kits (in my area they do sell new parts aswell) the guy said that the oils i have tried are all heavy smoke oils. he said to try Penrite or if i can find it genuine OMC oils, as apparently there is nothing in the carby that can cause it to produce that much smoke.
also i was thinking of changing the plugs again as they are fairly oily and a complete fuel system clean out.