Craftsman With CV15S rough idle, replaced carb, still there

[Wheel_horse_rider_2007]

Hello All,

I have a craftsman Mower with a Kohler CV15S that i picked up for free from a friend. I got it running but it surges at idle and blows white/black smoke. below is what i have done

Cleaned existing carb and rebuilt - problem still there
New plug - problem persists
Gas in oil - changed oil and replaced carb - problem persists
put an in line shut off on the motor and when i just slightly crack it, it runs great until it runs out of fuel

I don't understand why a new carb would not have fixed it???? I have a new coil on the way but im nt sure if im shooting in the dark with that...

Can anyone help me???

 

[Wheel_horse_rider_2007]

A couple more items

this motor is configured with a gravity fed fuel system and a single coil. No module.
I have the white wire disconnected from the coil

 

[Bod]

If you havent drained all the old fuel from the tank and filled with new then give that a try for your next step. I dont know if that engine has a governed idle or not, but check all your gov springs also.

 

[Wheel_horse_rider_2007]

Thanks for the advice. The tank has been cleaned and drained. I will check the springs. Am i looking for one to be completely off or just loss of spring tension?

 

[Wheel_horse_rider_2007]

I checked the compression on the motor and I am only getting 60PSI.... I put some oil in the cylinder and checked again with the same results. Could low compression cause this issue???

 

[Rokon]

I checked the compression on the motor and I am only getting 60PSI.... I put some oil in the cylinder and checked again with the same results. Could low compression cause this issue???

That's the automatic compression release kicking in on start-up.

You said in your original post: "put an in line shut off on the motor and when i just slightly crack it, it runs great until it runs out of fuel"

Even though you rebuilt the carburetor, it sounds like you still have an over fueling problem. The float/needle area is not working properly.

 

[Wheel_horse_rider_2007]

i have tried 2 brand new carbs, with no luck. I am finding it hard to believe it is the carb at this point....