Impeller Question
 

Just had new ones installed in my 500hps and lost water pressure on stbd engine shortly thereafter. Pulled it apart to find the impeller blades in perfect condition. Now I'm a bit confused. So, I start to examine the impeller a bit closer and find that the plastic hub is actually spinning inside the impeller. Has anyone had problems with this?

These are the first impellers I've seen with plastic hubs. All the impellers I've installed before had brass/bronze inner hubs. Maybe Merc has a new supplier manufacturing their impellers now? Anyone know the answer?

All the merc impellors I've bought have plastic inserts.

I take it they are genuine Merc/QS impellors and not aftermarket such as Seirra?

I just had the same issue with an Merc outboard impeller last week. I like the old style brass inserts much better.