Techno Water Pump

Right,

I recently replaced a fair few bits on my 96' Techno because the water pump seal had gone, that included the shaft as it was showing slight wear from the seal, and I did the bearings & impeller at the same time.

The shaft now supplied is a 2 piece assembly with a nylon drive gear, not all steel as the original. It matched up ok, and seemed to go in fine though.

However, upon reassembly and running it for a very (very) short time, there was a 'graunching'/grinding noise that I didn't like, so I stopped it quickly, and I've had the clutch out again tonight, only to find there are lots of little bits of white nylon in the bottom of the clutch case, and it would appear the grinding noise is the teeth being ground off the the drive gear for the water pump shaft.

So what does anyone recommend I do now? I'm confident it all went back as it should, but maybe the new shaft/drive gear is just plain wrong or doesn't mesh properly?

I'm contemplating putting the old one back in, but not sure if it is too worn, and there did appear to be some in/out play on it as the impeller was worn and inside of the water pump housing scored.

Cheers,

Sam