dt 115 smokes bad when trimmed down

[tammo]

I've had this 1986 suzuki dt115 since brand new.<br />First time into the water when trimming it down to take off, the engine started running very rough, smoked black not blue and when i accelerated it was chugging and smoking for the first 10 seconds til it cleared out.<br />High speed , no prob, but to start it it must be trimmed up as though the float levels were out.<br />back to the dealer and still the same. okay, so i've dealt with this for twenty years now and am wondering if anyone else has the same experiences.<br />new plugs every year, carbs cleaned out, new fuel<br />help!!!

 

[rodbolt]

Re: dt 115 smokes bad when trimmed down

definatly sounds like a float or needle valve issue, when ya trim it up the fuel runs to the front of the bowl and actually lowers the fuel volume in them, have the dealer raise the float level by about .050" those carbs are very touchy about the procedure to set them, if you just hold the carb upside down they are usually to low. the needles are spring loaded and you cannot compress the spring when setting the float level.<br /><br /> black smoke indicates excessive fuel in the combustion chamber.

 

[tammo]

Re: dt 115 smokes bad when trimmed down

thanks for the reply. initially when i returned to the dealer under warranty, they mentioned a float level adjustment or re-jetting to a smaller orifice but it didn't do much good, or maybe it just got the sunshine treatment. I will pull the carbs and compare all 4 float levels and take your advice on lowering the fuel level/ raising the float level 50 thou. I'll let you know how it went! thanks again