Hey guys, first post and i don't know if this is the correct part to send this but i am having problems with my HPI Nitro RS4 RTR3 evo. Well i've used it quite a few times and i found out that i had wore away one of the gears. My dad replaced these gears for me. The problem is, the car will not start anymore. Petrol pours out the exhaust without any sign of it trying to start. We had it starting a once but it cuts out. We have tried changing the carb settings etc to factory settings yet still no luck. Do you need a special tool to set the carb? Has anyone had the same experience? Any help or questions will be helpful. Thank you.