500 hours on engine, unknown hours on impellor
first impellor pic is rear cover wear, 2nd is down in pump.
why no replaceable wear plate, the college boys design it out ?

and someone needed more impeller changes as well. That formed a set with the rolled over blades long ago. That alone increases wear on top of when running.

The wear is nothing new. Very common since 2001.

Merc new pumps are way better now and alot easier to service by far.

Sea strainers help and more impeller changes helps alot as well to slow down the wear.

Way worse than mine was at 400 hours. I went Hardin Stainless and won't look back.

still once per year or 2 year MAX change of wear plate kit and gaskets plus use the OEM Merc impeller. Aftermarket impellers do not work that well in the Hardin kits -

I use the hardin ones as well. The wear plates rust up in corrosive water for what I have seen. Still best to have sea strainers. Stainless can still groove but way better than those Merc pumps. way too soft

thanks guys,
i watched a hardin marine video on their upgrade and turned it off as soon as they said
to reuse the rear section. then i searched on here and found out it's common so it'll just get
cleaned up and re used.

the new impellor kit is from mercury, plenty off room around the cool fuel and sea pump so annual
replacement won't be an issue

I run the Hardin pump. It is a very nice piece, and rebuildable if needed. It uses the stock backing piece that the hoses get attached to. There is a wear plate that goes between it and the impeller. The scoring does not affect it.

I would buy the one with the pulley as its already bolted to the pump from CP / Hardin. Yes its 100 bucks more but also a better looking pulley as well. I have found better belt alignment using their pulley already installed rather than pulling the old Merc pulley and reinstalling it. Keep in mind - better belt alignment can add to IAC longevity. Belt dust is an IAC killer.

Like I said the wear plates will wear and can rust.

These next pics are from a one year install by me of the CP / Hardin Pump - their pulley installed and their wear plates kit. The wear plates still groove and need replaced 2 years max or even less including New OEM impeller. Again one year old install and about 90 hours of run time on LAKE TEXOMA. Yes a Lake not salt water running.

.

I would use the CP / Hardin housing / pulley / kit rather than Merc set up inwhich is internally soft anyday of the week.

back side of the drop in wear plate.

Anybody know where to get a strainless water inlet/outlet to work with the Merc pump?

Either way you go just make sure you are replacing the pump, not just installing wear plates on the original. I have had both mine in under 400 hours lock up the front shaft bearing and allow the shaft to walk out of the front of the assembly. No damage done thank god. I noticed the squeaking and was able to pull the entire shaft out of the sea pump with no effort. This would have been a massive leak if it was on the water and let go. When the bearing locks up it now spins in the brass housing that act like another bearing surface until it enlarges the housing enough for the shaft to fall out.