Kohler Magnum 18 sputters and shuts down 30-45 minutes into use

snowfilmer

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  • / Kohler Magnum 18 sputters and shuts down 30-45 minutes into use
Kohler 18 Magnum on a Gravely 20G tractor. I'll drive it around and mow semi-tall grass (nothing crazy though - my yard is just big and it takes a while to get to all of it), and it'll mow fine for about 30-45 minutes. Then, Ill hear and feel it start to sputter/rev (like maybe it's running out of gas) and then it'll just shut off, and I won't be able to restart it for about an hour or so. One it restarts, the process repeats itself.

I only know a small amount about engines (still learning) so I can really only guess at the problem. The local Deere Country place that services it told me "seems like the engine is getting old, probably need to replace it soon". If that's the case, then so be it, but if I can make the repair (hopefully myself) and add another few years to the motor, that'd be awesome.

Here are all the symptoms/things I've noticed:
-Hard starting, always. Need to choke for a minute, then crank it with the throttle at 1/2. It'll turn over and over and almost start, then wheeze out. Repeat 2-4 times, slowly increasing the throttle, and it'll then start.
-Oil seepage onto garage floor. I'll put a piece of newspaper under the engine when I get it back in after mowing, and when i return a few days later, there will be maybe a 6-8" diameter spot of oil on the paper. Levels seem to be ok, I do add a bit more here and there in between changes.
-Oil (I think) in the air filter from time to time. It seemed a bit more before I had it serviced, but there's still some

I've had normal service done to it prior to the winter (I use it for plowing as well). When I started it up for mowing this spring, I noticed the engine "revving" a bit. I cleaned out the carburetor and that seemed to fix it up.
The fuel pump seems to be working, but I was still thinking of swapping it out just in case. The fuel filter looks fine and is relatively new.

So, any thoughts? Thanks in advance!!
 

mechanic mark

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  • / Kohler Magnum 18 sputters and shuts down 30-45 minutes into use
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snowfilmer

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  • / Kohler Magnum 18 sputters and shuts down 30-45 minutes into use
adjust valves engine cold, replace air filter, fuel filter, spark plugs, oil & filter. let us know how it goes, thanks.

https://www.google.com/search?q=how...ome..69i57.51355j0j4&sourceid=chrome&ie=UTF-8

Thanks Mark. I followed all of that except for "adjust valves cold" - can you elaborate a bit please? I don't need you to tell me step-by-step - I'll look up the details myself - but maybe which valves or where they are? Like I said, still learning engines.

I have had this problem continuing since I've had the air filter, spark plugs and oil/filter changed though. The fuel filter still should be swapped out for sure.

Thanks again
 
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