Found my overheating problem

Sorry to hear about the bad news. I just did a quick search, and there are a good number of water pumps on eBay. I had thought that I saw an impeller on there the other day, but it turns out its for the F40/208. (And another one for the 456, etc.). Good luck!

 

If I recall correctly, there is a special washer that goes under the nut that holds the impeller that gets bent up to keep the nut from coming loose. I could be wrong on that with the water pump, and it may just get torqued down. But either way, there was probably a washer. If the washer is missing, you might check to be sure it isn't blocking a passage somewhere in there.

If you have the pump out anyway, consider sending it out for a rebuild and have them install a new impeller for you set up properly. If the pump has never been rebuilt, having it done is good preventive maintenance, and not expensive. I had mine done by East Coast Jaguar in Delaware. There are plenty of places that do them, and use the larger bearing which is much better than the original.

Just a thought.

p.s. While you have the system apart, change the thermostat now too, and consider doing as many of the coolant hoses as you can if you still have the originals. Again, preventive maintenance. It's a messy but fairly easy job, and well worth the effort.