nikki carb head scratcher

ol' stonebreaker

Tractorologist
Senior Member
Member
nikki carb #97747 on a generac 4kw gennie. When you start it it's running overly rich. Pull the throttle arm back to idle it smooths out and then let the arm back off slowly it runs fine 'til I load it with my heat gun and then goes back to an overrich mixture. What I've done: removed float bowl and all is clean, main jet is clean, float is parallel to carb body when carb body is upside down, with carb body upside down float needle will hold a vacuum. I think the needle is sealing good 'cause the carb doesn't overflow while sitting. This is all done with the air filter off and it is new anyway. I set the valves to spec. Am I missing something simple??
TIA,
Mike
 
After trying a new float needle with no joy, I think I solved the problem. Using my tip drills I found the main jet was a little under .036" and slightly larger than .030". I filled the back side with epoxy, let it set up good and drilled it out almost to the orifice, then drilled the filled orifice to .030. Runs fine with no rich condition with my heat gun running off it which would make it load up before. Doesn't want to starve if I overspeed it. Hopefully mission accomplished. The only cause I can come up with for this condition is maybe enough wear on the needle stem and float to raise the float level just enough tho I've never heard of this happening.
 
Update: My contractor friend picked it up and used it to cut reliefs in a concrete slab with his large concrete saw and said it worked like new.
Mike
 
Back
Top