I'm looking at buying a very clean 2017 Cub Cadet XT1 with 160 hours. It starts right up and runs great. The only issue I'm really seeing is that it will not start when the engine is hot without the choke on. With the choke, it starts right up. This is a video of trying to start it with the engine hot and without the choke (at the end of the video when the engine starts, I put the choke on).
It makes a loud metallic clunking noise when cranking the starter that coincides with the slight up and down movement of the starter pinion gear, The clunk sounds much louder in person than captured on the video. I've never seen a tractor make this noise when cranking so I'm not sure what to make of it? Is this normal for the pinion gear to have that slight up and down movement and make that clunk? Also, the pinion will occasionally stick/hesitate for a second. My guesses on that would be weak battery, weak starter or valve lash needing adjusted. I did not have the battery tested but it reads 12.7v (I know that does not mean the battery is good but I'm leaning away from the battery). I'm guessing valve lash adjustment because it is also very difficult to turn the flywheel by hand and a couple times moving the throttle from full throttle to idle I got a backfire. The plugs are slightly fouled (picture attached), which could affect the starting too but it fires right up with the choke on. The air filter is dirty which could explain the fouled plugs. The tractor sat for 1.5 years, so the carb ports could be slightly blocked too. I did put fresh gas in with no change. Am I on the right track here? I'd appreciate input on the starter clunk/pinion up and down movement, not starting when hot without the choke and any other input. The big question is, what is a fair price for this tractor?