Lower unit impeller, metal sleeve or no sleeve??

[crazy charlie]

I see more and more impellers over the years eliminating the metal sleeve and
going with completely rubber one piece design.Mercruiser,Yamaha etc.The logical reason I can see
is cost.No metal has to cost less to produce.I have avoided the non metal sleeve impellers but recently have heard a very good reason for no metal sleeve impellers.i have only had it happen once in my 30+ years of boating but every so often does an impeller fail and it fails between the metal sleeve and the rubber .Similar to a spun hub on an older prop.Whether it spins or tears away from the rubber
the possibility DOES exist. I am proof when I tried a blue "run dry" mercruiser impeller
many years ago and it failed at the metal sleeve .A completely rubber impeller eliminates that possibility I was recently told.I never thought of that and am considering trying one
on my Yamaha outboard.Makes sense to me, anyone else thinking like this? Charlie

 

[crazy charlie]

Wow!!!! Nobody????

 

[dingbat]

Between the development of new plastic compounds and advancements in injection molding, I could see the metal insert going by the wayside

I’m surprised they didn’t go to some sort of plastic (Polyethylene) insert sooner

 

[99yam40]

which ones use a metal sleeve?
all the outboards I remember seeing were not metal around the shaft, but the wear plate and cup were metal

 

[crazy charlie]

which ones use a metal sleeve?
all the outboards I remember seeing were not metal around the shaft, but the wear plate and cup were metal

Pretty sure the last water pump sec I did on my Yamaha 200 saltwater series was a metal sleeve.It was an oem kit. Mercruiser for sure(not an outboard).Charlie