Erratic carburetion on the M12 Kohler

[Bahmi 4]

I ran and mowed with my new, to me, 312-8 today. Went about 20 minutes. Engine was then shut down for 15 minutes. Tried to start it again, nothing happened. Nothing. Is this characteristic of some well known problem with the engine or carburetor?

 

Where do I start to diagnose this quirk?

 

thanks

Just now, Bahmi said:

I ran and mowed with my new, to me, 312-8 today. Went about 20 minutes. Engine was then shut down for 15 minutes. Tried to start it again, nothing happened. Nothing. Is this characteristic of some well known problem with the engine or carburetor?

 

Where do I start to diagnose this quirk?

 

thanks

While running, the engine at higher speeds and while just sitting still, was searching. Run, search, run, search.  No adjustment seemed to make any difference.

[953 nut 51,720]

          I would start by replacing the spark plug, air filter, fuel line and fuel filter. Use non-ethanol fuel (ethanol will crap up the fuel system) and add Seafoam fuel additive to clean the fuel system. Lots of problems are the result of deferred maintenance.

[squonk 38,936]

With the searching issue, check for slop in the throttle shaft where it passes thru the top of the carb. The cable pulling sideways on the throttle will cause it to wear into the carb body causing an air leak. 

[prondzy 3,867]

I have had 2 magnum 12s with bad fuel pumps, the plastic pumps have a felt like material used for the check valve seats i beleive. This material breaks up and lodges in the check valves holding them open or shut giving you a no start condition. Try swapping with a known good fuel pump. A metal one from a K series will work just make sure you get the arm on the top side of the camshaft lobe.

[wfrpalm 217]

When you say nothing happened do you mean it would not turn over or would not start?