Kohler EFI woes

[pineywoods]

Working on a neighbor sawyers wm lt40  equiped with a 28 hp fuel injected kohler engine. They ran it all day monday, but said it sounded like it was running on one cylinder and was down on power. Next morning it cranks over but wouldn't start.
Spark plugs look ok, but swapped them out anyway. Electric fuel pump cycles up, builds up pressure, then shuts off normally. Hooked up a test light (the on-board malfunction indicator light is burned out) and went through the proceedure to display fault codes. Flashed code 61 which says no fault codes. I downloaded and read the kohler service manual and talked to Mike at woodmizer Indy. We've about come to the conclusion that both injectors are plugged up. Circumstantial evidence. Thieves stole the fuel tank off the mill. Owner hooked up a fuel tank from his boat outboard motor. Probably still full of OLD ethanol gas with  lots of 2 stroke oil in it. Current plan is to bring the mill to my shop and continue trouble shooting where I have tools and equipment. I will follow up post what we find...

[MartyParsons]

Hello,
   Do you have spark at each cylinder? Should have a modified spark plug to check for spark. Never seen a coil go bad on one of these engines on a WM but have seen them fail on lawn equipment. I have also seen push rods come off if the valve sticks.
Will it start on 2+2 carb cleaner sprayed into the intake?
Marty