2013 Roadster No Starty!

The catalog only shows a complete unit, no serviceable parts. The pump's mechanical seal is likely a press fit type and would need to be done in a shop with the right tools.
 
Well I went to remove the plugs and didn't get very far since I couldn't find the 18mm spark plug wrench I shaved on the bench grinder to fit the holes on the rocket. I remembered telling my daughter to pick out a good plug socket out of the tool drawer for her a couple of months ago. Called her and sure enough that was the one she chose. I asked her why that one? "Well, it looked chewed and beat up so I didn't think you would mind me taking that one." I'll be getting it back tonight
 
You can try replacing the seal, searching the web yield's part number P99T:G858 as an aftermarket seal for the water pump. They are "available" on eBay.
 
You can try replacing the seal, searching the web yield's part number P99T:G858 as an aftermarket seal for the water pump. They are "available" on eBay.
This is what I'm going to do, rebuild mine if it turns out to be the pump leaking onto the crankcase. Again, I'll pull the plugs tomorrow after my plug socket shows up to see what's going on in the cylinders. Need to be sure its not the head before I throw more dollars on unneeded parts.
 
While I was doing that, I'd apply air pressure to cylinders to check for leak.