Hi Guys

I have a cat with 2 X BF135's that i purchased a few months back that has had a long history of suspect overheating and alarm problems prior to my purchase. It has taken me a good long while to get to the firing up stage that I'm at today due to needing a whole heap of fuel system parts etc etc. Long story short.. fired them up today and port engine runs sweet and pee's good. Stb engine started fine and shortly after intermittent alarm started... engine was not peeing. I am running both in large troths so was able to reach into them ( with engines running in neutral ) and could feel suction on the water intakes on the good engine and no suction on the other "no pee" engine. Pulled the leg to inspect pump and found fresh grease where previous owner had obviously been not too long ago. When I pulled the pump housing off the drive key fell out ..and I'm not sure if it was located in impeller correctly or not. The impeller housing and gaskets all looked new.. Where the O ring sits in the impeller housing there was a gasket glued in place on top of this. Going by the parts manual there is only 1 gasket and it sits below the impeller cover plate... so this leg has 2 gaskets fitted where should only be 1. Pulled what I assume is water / oil seal asm below the pump and all looked good.

My question is if the water pump gaskets had some slight leaks - even if not obvious - would this cause total loss of water pump function. Is there something silly that I am missing?

Thanks in advance for any advice you can offer