LHW0050PQ washer started making grinding sound when draining. I have opened it, removed the drain pump, opened it - 3 screws to separate the motor from the cap with the impeller. I have discovered that the impeller was lose and was not sitting on the rotor. I could not figure out if it was broken off the rotor. I have noticed that I can put it back onto the rotor, it clicks and then it is sitting quite securely in its place. But with a bit of force I can get it off the rotor. I am wondering if the impeller is supposed to be sitting on the rotor solidly or it is expected to get off in case if something blocks it to prevent the motor being blocked and burnt. Reassembled everything, tried to run a short cycle - the sound seems to be fine and the drain is definitely working properly. Should I start thinking about new pump assembly or this is something known?