MD321S Hybrid question

[Tyler]

Guy's I have a quick question that I am a little worried about. I have just fitted my RCM headers and had to wait for a heli coil kit to come as one of the exhaust studs had shat itself. So I covered up the turbo and wrapped it up and put in the boot until the coil kit came.
Once I received the coil kit recoiled the hole and then thought I would inspect the turbo(a week later) checked for play and there was non thank god.. but noticed that when I spin the impellor it stops pretty quick it does about 1 resolution then slows itself right down, no grinding at all or any play left, right or up or down. I thought that when you spin these they keep spinning and slow down slowly ( or am I being over cautious )
When you rev the car slightly and then turn the engine off the turbo used to carry on spinning for some time.. (but to be fair have not driven the car in about 5 months so could be just over worrying)
It had a rebuild and had a new GT30 core and a 7cm hotside housing instead of 8.