Stalling The scooter will run fin for about 10 mins the it will start to stall out. it becomes hard to start and will only run for a couple of mins before stalling out again. it will some times take 5 to 10 mins to get scooter started after it stalss out

run fault codes
check for wiring on crank shaft position sensor or cam position sensor/s
it will be something that was affected by the belt replacement procedure

I would start by getting a can of carburetor cleaner and have it 'at the ready' and try the 'start, run stall, start run stall' operation again. Only THIS time, once the engine begins to stall, give it a couple of quick shots of the cleaner into the air filter to see if it stays running on the cleaner.

If it does, then it's still a fuel problem. If it doesn't, then it probably an ignition problem. I would be sort of leaning towards the ignition coil getting weak. The reason I'm saying that is your statement about it running (I'm assuming cold start) for at first, 10 minutes then it stalls. Start it again and it runs for a couple of minutes and stalls again.

This could possibly be from the coil getting warm/hot and not producing the needed spark. After a 10 minute run it simply gets too hot and stalls the engine. After the next restart, the coil is already warm from the engine and so it don't take as long for the coil to get hot and stall the engine again.

Hope this makes sense and helps you out.

As with any no-start situation, you need to know if you have spark to the plugs, fuel to the injectors, and normal compression to proceed.

Check your coolant level and overflow bottle for proper fill. Or try running it With radiator cap loose to see if it still stalls. If it still stalls and coolant levels are good you need to check temp sensor. May be more than One. If you did install a new one, it may have been faulty or damaged. If all that fails then try an idle positioning sensor. The spring may be worn.

Could just be cold blooded. Does sound like fuel is being primed to be able to start. if a person has to use starter fluid, then that means the carb is not getting enough gas at start up. Carb will most likely need to be pulled apart and soaked in solvent or equivelant for couple hours. Make sure float is adjusted properly and fuel filter is clean

a bad crank sensor can cause this. shuts off while going down road, and will start about 10 min, later with no problems runs fine until it quits again. hope this helps,

Your carbeurator needs to be rebuilt.

i know this may sound stupid but if your battery is old or a little weak on this vehicle the idle air control solenoid will act speradicley hunting for were it should be and the vehicle will stall.replace battery

sounds like the timeing belt is bad.

You need new timing belt and gears. Buicks gears are made of plastic, and become a big glob. Nothing for the timing belt to grab onto.