XRAY - Model racing cars

Hello everyone,,
I was at the track and it was great but when I got home and I was cleaning my NT1 I pull on the throttle link to disconnect it from the carb and the carb just came off in my hand. Is this normal that the carb comes lose?? THis .12 Ninja engine has about 2 gallon though it what can I do?? Do I need to seal it how do this carb come from the factory?? Also Does the factory seals these?? I notice it has an O - ring.. Also if I need to seal it was sealant would I need and how do I do this with out messing up the engine??


Thanks for all your help..