lifter or valve sticking

[mntbike]

i have a cubcadet with a CH18s Kohler. I suspect the hydraulic lifters are sticking as it will backfire and the mechanical fuel pump stops working. This will happen after 20 minutes runtime. Other than pulling the heads, is there an additive to possible clean internal to free what is sticking?

 

[Fish]

It sounds like a simple fuel starvation problem, first thing to do is make sure the fuel tank cap is venting, then check fuel lines for cracks, clogs, dirt, water, etc..

 

[exotion]

Seafoam in your oil will clean it or pour seafoam directly into the plug hole crank it let it smoke for a few turn it off let it sit for 5-10 mins crank it up let it run until you stop seeing smoke . But I agree with above sounds fuel.