new impeller not pumping much water?

Generator stopped pumping any water at all. I bought a new impeller and went about changing it for the first time. Well, I got my son to do it because I'm not sure I could fit back there. It's practically a blind job with extremely limited access.

Everything seemed to go well except that we (my son) couldn't get the impeller pushed in. We eventually figured out that the little bar in the middle of the impeller was ever so slightly too large. I took out the old bar and put it in the new impeller. Presto! Slid right in.

After getting everything tightened up and the water back on, we tried it. We get very little flow of water out, but certainly not enough. I'm installed many impellers over the years and have never had an issue. I'm not sure how to diagnose what the issue might be as I can't even get my head over there to see it.

Ideas?

Not sealed well and getting air into the housing?

What did the old impeller look like? We're vanes broken off? Meaning, are you sure it was an impeller problem and not a clogged intake or strainer. I had a similar flow problem in a fresh water river and it turned out a tree seed pod was the was exact size to wedge into the intake opening. I had to dive under the boat and pull it out.

I had a similar problem and my intake was full of leaves.......

I'm also wondering if the housing plate isn't sealed well. I'll be sending my son down there again.

Yes, it was an impeller issue. Fortunately there were no broke vanes, but the impeller was split open right where the pin comes through the side. Very disappointing in the fact that this impeller was 8 months old and had about 5 hours of use.

I have cleaned out the strainer (which it needed, but didn't seem enough to be affecting flow) and I also dove on the intake. Very hard to see with the eye, but I felt around and it seems clear. I also had forgotten to shut off the seacock when I first opened the strainer and it definitely seems to have good water flow from the seacock to the strainer.

Update: It's working better, but I don't know if it's fixed completely or not. I just don't know how much flow it's supposed to have. The only thing we did today that I think may have helped is that "primed" the water line from the strainer to the pump. It was barely spitting anything before we did the prime and now it's running about how it was before. I'm just wondering if this flow is good enough and maybe why the first impeller failed so quickly. I took a video of it - check it out.

I'm no expert, but it looks pretty good to me.