gas smell

[zepman]

I have a '76 Johnson 85 outboard that has begun to smell gassy. It seems to run o.k. at mid to high range but is missing a little at lower rpm's. Also, noticing oil deposits or "black **** " appearing around the motor. When i run the motor for awhile and then stop and fish is when the gassy smell will really become apparent. I also noticed this morning when I went into the garage that the gassy smell was still quite strong. I'm not very mechanically inclined but would like to get your opinions on what you may think is wrong here. Is this a carb issue or a fuel pump? Thank you

[Diezel350]

I would check all the connections and hoses first to make sure they are not the culprit.
If you find no leaks there go to the carb. Sounds like the needle and seat are not doing their job inside the carb. When the motor is not running the gas will slowly leak by and spill out of the throat of the carb. As the gas spills out the carb and flows down the motor it picks up all the grease along the way and causes the black streaks you are seeing
It sounds like a good carb cleaning may be in order too for the rough low rpm running.
Needle and seat replacement is pretty easy once the carb is off.

[Wavey Davey]

I have recently noticed the same problem on my '73 Johnson 65HP. It's not leaking from the fuel line connections, checked that 1st.
Took a quick look at the motor with the cover off and couldn't see gas leaking.

It could very well be what Diezel describes.
The boat's up north and I'll look closer at it this weekend. Shouldn't be hard to remove the air cover to look at the carbs. However,
there are 3 carbs and I've never taken them apart before. Had a mechanic do it a few years ago and clean them good.

My question is, if it is leaking gas past the needles and seats, how hard is it to replace? Can I do it myself without screwing up the carbs? I don't have a repair manual but could probably get a hold of one. I have no idea what's involved, has anyone out there done this before and have any tips or advice?

Thanks, Dave

[Diezel350]

Wavey
If your carbs have a air box over them take it off and get a better look at the carbs to be sure the leak is not from one of the carb gaskets.
It is possible that a bad float in one of the carbs is not letting the needle seat properly also.
I would suggest a manual if not familiar with the inards of a carb.

[Wavey Davey]

Diezel,
Thanks, I'll investigate further and go from there. Once I determine exactly where the gas leak is coming from, maybe I can fix it without tearing the carbs apart. Replacing a gasket I could handle.