its important when receiving a rc to check them over real well (I personally totally disassymble em) and check all the screws and locktite the ones that are metal to metal....I do not however locktite my engine mount screws (the ones holding the mount to the chassis).. reason being is the engine mount aluim is soft and although its easy to get the locktite off the screw it isnt so easy to get it out of the hole...I've stripped the threads on numorous engine mounts due to this....I pull my engines frequently for maintanance and cleaning...every since I've quit putting locktite on them and just check them quite frequently I have yet to strip the threads on the mounts....