OE Mercruiset has kits with wear plates and a tiny bit shorter impeller to use’m. I wrote a thread with this info here:
Boatfreaks

i know, you need to be a member to see it. Oh well, taje 2 seconds become a member if you want to see it. Lol

Agree with SB

I use these with the stock housing:

https://www.mercruiserparts.com/merc...9-impeller-kit

I also replaced the back plate with the OEM plastic one which also comes with wear plates.

https://www.ebay.com/itm/29341263321...hoCcjAQAvD_BwE

Cheaper than the Hardin.

Just a little more info needed here …. What rotation the impeller must be reinstalled?? Im i supposed to turn it counter clockwise while pushing it into the pump ?!? Forgot to take pictures 🤦🏻‍♂️

Doesn't really matter, it will flip to the correct orientation as soon as you spin the motor.

i dont know why but my brain wants it to be in the correct position before startup 😂

From memory I believe it rotates counter clockwise lookin from the back. Search YouTube....hundreds of impeller change videos.

Once you jam it in there and lube it up, you can hand rotate the pump and you will see how it flip/flops depending on direction fairly easily.

Yes, I realize that last sentence sounds incredibly pornographic.

You can see the impeller orientation here. I just did the Hardin swap a few weeks ago
https://cimg3.ibsrv.net/gimg/www.off...08cfe25911.jpg

screenshoted 🫡🫡

thanks to all

Did any OEM apps have a plastic backplate?
I thought they were all brass?
I did learn that there are wear plates for the back plate: Like this.

Although appears they used them on the air actuated drain system backplate that had a recess milled in it.
According to the pictures in the tech sheet.
There is a nice Mercury PDF tech sheet at the link you provided.
I thought this site had the ability to upload PDF's. I never seem to get it to work.

Anyhow if anyone is interested go to that impeller link and click where I screenshot.

https://cimg1.ibsrv.net/gimg/www.off...761b1d9909.png