Greetings All
A customer brought in a grain auger with a Kohler ECH749-3062 S/N 4513500871 EFI engine that had no power and was blowing black smoke. The anti-icing tube had never been removed since the unit was new in 2015. The exhaust deflector tube was in the sox-o'clock position, so the engine was breathing in its own exhaust and the air filter was black. The rear heat shield had come loose on the muffler and one of the mounting lugs had broken out allowing hot exhaust to blow onto the electronics on the side of the engine.
I've replaced the muffler assembly and air filter, repaired the heat shield and installed a new exhaust deflector in about the 4-o'clock position. The oxygen sensor was caked thick with carbon which came off with compressed air. The sensor also checks out according to the resistance specs and the anti-icing tube has been disconnected. The engine appeared to be running fine when it left my shop, so figured it was fixed. Received a phone call from the customer saying the engine now has a lot more power, but the snow is turning black under the exhaust deflector pipe. This tells me the engine is still over-fueling. Any suggestions? Thanks,
Sky