Vroom 260 runs for 30min, then stalls By larrys2dogs (Read 369 times)

[larrys2dogs]

We have a Vroom 260 (knock off 257cc) that has run well for a long time. Recently, it began having problems. It will run for about 30 minutes, then it shuts down and won't restart for 3-4hr, then it will run again. Temp is OK. Anyone have any ideas? All help would be appreciated.

[Alleyoop]

I would first adjust the valves, it appears they are expanding and not closing and the motor is loosing to much compression. If it still does it after you adjust the valves then I would look at the carb and after it dies right away open the drain to the carb bowl and see if the carb bowl has fuel it may not be filling up fast enough and it is dry. But I would not think it is that since it will start after it cools off. Points more to the Valves.
Alleyoop

[kz1000st]

Just to put it out there, it could also be the coil or CDI heating up, crapping out and then working after cooling off.

[Bashan]

Your tank venting might be plugged up. It runs until enough vacuum builds up to stop the fuel flow. After it sits the tank pressure normalizes and off you go. Try running without the cap screwed down and see what happens.