[gravelyman66]

okay guys i have a cub cadet 108 (yes its not a gravely but you guys are amazeing with engine help) with a Kohler K241 (10HP) it starts right up and runs for a few minutes then it loses power and spits then dies then backfires (in that order) it has a new carb a new coil,points.condenser,spark plug, fuel lines, new head gasket all thats new it just wont stay runing and im out of ideas i dont want to part this out either
thanks, Gravelyman66

 

[BUDSVTX]

OK what is it with K241's in the last 2 weeks. Mine, then yours. Please check my previous post. I did the same thing and nothing, ran like crap. What I found was a bad condenser wire at the coil,was making a connection about 99% of the time. I put on an old condenser from my junk box and it runs great. I cut about 1/2 acre and it quit. Found the coil almost to hot to touch. It started up but ran real bad, made it back to the shop and put a fan blowing on the coil to cool it down. When the coil cooled down I was able to cut for another 30 minutes (got dark had to stop) without any issues. I will change the coil and condenser. Hope this helps.

BUD

 

[jrd]

Does it start right back up, ie if you wait for 30-60 sec? If so, I'm thinking fuel delivery. Probably got a filter that's almost full up with crud, so it's passing just a trickle.

If you have to wait 20 minutes before it will restart, that sounds more like a temp problem, perhaps a condensor or coil going intermittent with heat. Except that you've already changed that stuff out. Besides it doesn't sound like it's running long enough to get good and hot.

So I lean toward a line or filter or something being clogged.

 

[gravelyman66]

lines aare new filter is new it starts right back up i.e 3seconds runs great the n blows gas back out of the carb

 

[jrd]

So it backfires, then blows mixture, or liquid fuel out the carb intake?

I wonder if you have a fuel pump/carb problem? I'm not an expert on kohlers, does the 241 have a fuel pump like my 301? If the carb isn't set up right, such that the pump is pushing fuel past the needle valve, that could causing flooding, and also lead to fuel dripping back out the carb once it stops running.

 

[gravelyman66]

yes it backfires then blows fuel back out there is no pump in this its gravity fed tank is right about the carb ive ran sea foam trhough it that marval mystery oil sprayed the carb wit hseafoam while running and acts teh same

 

[gravelyman66]

im out of ideas on what i have to do i dont want to rebuild it but if i have to we will

 

[jrd]

Well ok, if you're seeing fuel dripping or spraying back out the intake, that can't be right. Does it leak when just sitting, ie not running?

I guess at this point I'd be looking at opening up the carb and making sure the float and needle are correctly set up and working.

The original description sounded like maybe fuel starvation, but this sounds like there's too much, not too little.

 

[gravelyman66]

nope it doesnt drip with its just sitting (not running) it dont drip when it runs just when it backfires it shoots gas out

 

[gravelyman66]

just double checked the carb and everything is set where needed to be runs for maybe 1minute30seconds than dies

 

[arcam8123]

Here's a shot in the dark. Have you tried to run it without the fuel cap on the gas tank? If the fuel cap vent is clogged, the tank will go on vacum and the gas flow will stop.

 

[BUDSVTX]

Backfiring??? Firing a little to soon. Check your point gap, get it close then put a timing light on it to insure it is dead on. When was the last time you set the valves? Intake valve may not be fully seated when it fires. If it isn't seated, this would explain backfiring through the carb.

BUD

 

[gravelyman66]

Ummm how exactley do you check the valves

 

[floats12]

http://www.oldgravelys.net/pdf/Conv_10_10A_12_Serv_Man_0675.pdf See starting at about page 32, no real step by step but the pics are self explanatory as to where/how the adjustment is made once you get to the right page and compare it to your engine. Basically the engine must be cold and at TDC on the firing stroke so that the valves are fully closed. IMO it is better to be a little on the loose side rather than tight. And use a little Marvel for lubrication. I use StaBil year 'round in all gas and there is StaBil for ethanol if you have ethanol in your gas. Jim

 

[gravelyman66]

okay ill try that when i get the new head gasket

 

[Mickeymotormount]

Have to agree: sounds like the intake valve is being held open a little. With all the parts that have been replaced, one of the only things left is compression and valve clearances. Be sure there is no carbon around the seat as this also can hold the valve open a touch. Adjust as necessary.

Ignition timing should also be checked. I feel the valve adjustment is the culprit though. Good luck.