to loosen the press fit pinion and not have any other gears broken is a first ive seen, i guess when the pin broke, the motor overpowered the press fit... Bill, locktite 609 or permatex green is what you want, super thin and used as retainer compound, wicks well, or you can just solder it like a slotcar pinion, im still waiting on my nitropro 500, seems someone at usps needed a new servo worse than me, my BK-7002HV didnt have screws through the case securing the motor either, even though the motor was threaded and the case was countersunk for hardware... that thing is still going on 5 years even with a bunch of gear slop, seems like a manufacturing of scale cost benefit deal, cheap out on the screws saves that much unit cost after x amount produced