Hello, my name is XXXXX XXXXX I can help you with your question.
First of all are you sure that the engine is actually running hot or is the temp indicator lamp coming on or flashing at you? One of the problems that we are starting to see on the older 6x4 gators is the harness in the frame rubbing thru and shorting out wires. The Temp switch for example completes a ground circuit which in turns on the indicator lamp. A short to ground in the wire leading to the indicator lamp would cause the lamp to come on when there really isn't a problem. How long do you drive your gator before the lamp comes on?
Let me know and I will help you narrow down the source of the issue.
I apologize but the only reply I see is your last one. Unfortunately I don't see any additional information that would have been posted yesterday. Would you mind reposting the information and I will do my best to get back to you.
As a general rule John Deere Gasoline powered gators have a much larger cooling system then is needed for most circumstances. It sounds like you have done a good job in flushing the radiator and verifying flow through the engine. While the thermostat should be in place for proper cooling I still wouldn't expect to see it over heat in such a short time.
If the smoke you describe is white then it is getting coolant into one of the cylinders. There are two different causes on the gas engines that typically cause coolant to get into the cylinders. The intake manifold is a coolant transfer tube that acts as a bridge between the cylinder heads. In some cases the intake manifold gaskets will fail and cause the engine to ingest coolant. Its rare but it is possible that you could have a failed head gasket. The easiest way to see what cylinder is ingesting the coolant is to pull a the spark plugs and check the color of the plugs. Coolant acts as a steam cleaner in the combustion chamber so the spark plugs will turn light gray to white depending on the quantity of coolant ingested.
Just a tip that you may already know, the coolant air bleed on the top of the engine is the small plug in the top of the intake manifold. Failure to bleed the air off at the intake plug often results in trapped air that can cause the engine to run hot.
Lastly check your oil level if you haven't already. Gators that idle around allot will sometimes fill the crankcase with gas thus raising the oil level. Once the oil gets high enough the engine will start to smoke blue and get hot.
With any luck this has helped to narrow down your cooling issue. If you are satisfied with my answer please hit the "Accept" button. If you need further assistance please feel free to ask.