Yamaha f100 smoke when idleing

Snarl2004

Recruit
Joined
Sep 11, 2009
Messages
3
You know when cars are cold and you start them up they have the white smoke or whatever come out the tailpipe?

Well my yahama f100 does that when idleing. Not when it's at speed just when it idles and I was woderong if that's normal.
 

andrewmac

Cadet
Joined
Aug 25, 2009
Messages
21
Re: Yamaha f100 smoke when idleing

Snarl2004,

If it is smoke from engine oil then no, its not normal. You can check this by removing the spark plugs and looking for oil saturation or carbon deposits. It would be a good idea to compression test as well, or even better a leak down test. Does the engine consume much oil during normal use? It shouldn't require adding oil very much at all.

If you run the engine in cold water like I do in the Northeast it could be the steamy water coming out of the warm motor into the cold water. This would be most noticeable during idling and least noticeable when running along at a good speed. This does happen sometimes, but if you use the boat in a warm climate its probably not this.
 

Snarl2004

Recruit
Joined
Sep 11, 2009
Messages
3
Re: Yamaha f100 smoke when idleing

Its deffinitly not burning oil. I think it is the steam. I live in massachusetts. You can only notice it when the engine is ideling. Thinking about it it makes sence its steam because you only see it once the engine is warmed up.
 

andrewmac

Cadet
Joined
Aug 25, 2009
Messages
21
Re: Yamaha f100 smoke when idleing

I live in Maine and see it a lot, especially on cool, humid mornings You should take off the cowling and feel the motor to see if it's too hot just to be sure. You should be able to touch any part of that motor without burning yourself. Be careful in case its too hot though.
 

connemaraisland

Seaman Apprentice
Joined
Aug 15, 2010
Messages
30
Re: Yamaha f100 smoke when idleing

Don't worry about it mine does this as well on cool humid mornings, also when you shut the engine off, trim the engine up a little to prevent oil seeping down the cylinder bores. Also be aware that the oil should ONLY be halfway up the checkered part of the dip stick max - if you have more than this much oil in it suck some out as you are not doing it a favor - Bob
 
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