"How'd the old impeller lo
"How'd the old impeller look? You can pretty much tell if that was the problem or not, just by the condition of the old one. If it's missin fins, and pretty much chunked out. Then it was obviously bad. Also, something to consider.... if it was missing fins and chunks, they had to of gone somewhere. It's a good idea to chase thru your cooling lines and look for any obstructions. Best you can anyways. And yes, it's going to seem like a really tight fit. It's recommended that you rub some marine grade grease around the inner s.s. liner too."