@david_alex Troy-Bilt uses a few different engines for their equipment. We would need to know what engine your riding lawnmower uses. Most commonly would be a Briggs and Stratton engine. White smoke from a car is typically coolant, whereas a riding mower like yours does not have any coolant per se. Hence the grey smoke is not caused by a coolant issue. Commonly issues like blue/white smoke is when your engine gets to much fuel. Like you already stated :
"- Check the gas lines for leaks. Check the carb for leaks and tighten it if it's loose. Also, check the carb float. It may be sticking open, letting it flood.
- Check your oil level? Also to see if it may smell like fuel."
Now we need to know if you checked those things out. If not, then we can help you with that.
The other things to consider as a cause for this are:
-Clogged air filter
* Initially it would be black(ish smoke but eventually your engine will pull the air it needs for combustion from the crankcase. With that air would also come oil into the combustion chamber leading to white smoke.
-Oil level high
- To much oil will cause an increased crankcase pressure which could force oil into the combustion chamber leading to white smoke.
-Bad piston rings or a leaky valve train can also allow oil into the combustion chamber. All of this could lead to a white smoking engine.
To check on that, remove the spark plug(s) and look at the face. Let us know what it looks like or post some pictures of it. I would expect it to be oily and sooted
We would need to know what exact engine your Troy-Bilt has. If unsure of anything you can always post pictures of anything with your QUESTION. For that, edit your QUESTIION and follow this guide
Adding images to an existing question
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