Did you use a Kohler brand fuel filter? They are picky.

I used a fuel filter from Sears, by Craftsman that listed Kohler in compatibility. But it's not an exact replacement. The local small engine shop had told me in the past that the mfr of the fuel filter generally doesn't matter, but if these engines are that picky, maybe I can try the old one I still have.

Plugged vent on the fuel cap?

Yes on the coil. Yours may get the updated coil kit. I do 3-4 SV735s (0006 spec seem common) for this a year. The odd thing is the Sears look up gives a different number than recommended by my Kohler distributor. Basically as ewalk stated, you drop spark on a cylinder. I just use my inductive tach to check for spark. Or use good spark testers, or simply momentarily shut it off, and ground the lead for either plug and see if it makes a difference when you restart and engage the deck. BTW, you can put just about any fuel filter on these as they have a pump.

I'm with Tom (Hi Tom) on this that it might be ignition.

Spark testers are pretty cheap.

You could stick it on one plug and compare spark when running good and again when bad.

It/s not really good practice to try grounding the lead and seeing if you get spark.

The problem is the coil buils up high voltage. IF the spark plug lead ISN'T grounded, this HV tries to go SOMEWHERE. If it can't fire through the SP lead, it'll tend to break down the coil(s) internally. They are just too spendy for self inflicted damage.

You might also look at the condition of the pulse line to the fuel pump. Cracks etc. can affect FP performance. Maybe as things heat up, an existing crack opens up a bit more? Just a longshot here.

I'm thinking you guys are right about the ignition. I haven't experienced this type of problem before to diagnose things that far. I kept researching all afternoon yesterday, and I had started seeing issues with the ignition modules on Kohlers. They had issued a parts bulletin with the conversion kit for the SV735. I just ordered it, so hopefully that'll resolve my problem. I'll try to post an update this weekend, if I get the part before then. Thanks everyone for the input.

That's what were here for Chris "To Serve and Protect" Yes in the Ground Potential Practice's , seen a lot of Coil Ignition Modules fried back in the Snowmobile Racing Days when a good ground was not established while Testing ! Hi Bill , good to see you back . Tom, are you getting much use from that New Drill Press ?

Hey Bill.<insert ewalk here> Not lots of drill press action. It did turn out to be a nice addition though and I appreciate your input.

Drill Press?? You've got me Tom.

I can't at all see where the confusion comes in Bill! Good to see you back around BTW.

UPDATE: I received my parts order this morning. The conversion kit came with the coils and a little wiring harness (which basically replaced the old wire connectors to the old coils). I went to work on replacing them, and wired it accordingly. After firing it up, I started mowing the lawn. I mowed for about an hour, and it ran perfect the whole time. I'm pretty confident now that my problem is resolved. I'm glad I held off on bringing it to a shop for repair. Thanks again for everyone's help.

Great to Hear Chris , some Lessons Learned and $$$ Saved ... Congrats Bro !